Bill et al., 2011

SafetyAnalyst Evaluation and

System Requirements

Assessment

Final Report

July 2011

TRAFFIC OPERATIONS AND SAFETY LABORATORY

University of Wisconsin-Madison

Department of Civil and Environmental Engineering

2

EXECUTIVE SUMMARY

SafetyAnalyst is the state-of-the-art analytical tools for use in the decision-making process to

identify and manage a system-wide program of site-specific improvements to enhance highway

safety by cost-effective means and the only one being undertaken at the national level. The

Highway Safety Manual (HSM) has been developed to make estimates of traffic safety

performance in the same sense as traffic operational performance estimates using the Highway

Capacity Manual (HCM). HSM is intended to provide a quantitative basis for estimating the

safety performance of roadways and for estimating the effects of proposed improvement

projects. As a result, parts IV and V of HSM will include the basic concepts that have been

developed for SafetyAnalyst. Highway agencies will be able to use SafetyAnalyst to investigate

the potential benefits of specific safety improvements and conduct a thorough economic analysis.

The goal of this project was to implement and test the use of SafetyAnalyst using Wisconsin

data, evaluate SafetyAnalyst analytical functions, and validate the results. Recommendation

from the evaluation will be considered to enhance current practical applications. Based on the

defined objectives and tasks, there were two main parts of the project.

The first part included tasks undertaken to prepare and evaluate Wisconsin Data for use with

SafetyAnalyst and successfully import, post process, and calibrate the data. Details of the first

part of the project are presented in the following reports.

1. Appendix A

2. Appendix B

3. SafetyAnalyst Data Import Progress and Issues

4. Wisconsin Data Evaluation and Assessment for SafetyAnalyst Data Import, Post

Processing, and Calibration (First Dataset)

5. Wisconsin Data Evaluation and Assessment for SafetyAnalyst Data Import, Post

Processing, and Calibration (Second Dataset)

SafetyAnalyst provides a number of methods to import agency data depending upon the format

and availability of data. A detailed assessment was made of data elements required by

SafetyAnalyst and their availability at WisDOT. Details of this assessment are presented in

Appendix A. In view of this assessment, a choice was made in terms of the best data import

procedure given the many options available in SafetyAnalyst. The detailed step by step

procedure implemented to import data into SA is presented in Appendix B. Once a decision has

been made on the import procedures, WisDOT business data were requested and received in

CSV format and uploaded to an Oracle database. The data import process was initiated which

resulted in a number of issues and challenges mainly because of the shortcomings in the data but

also because the software itself was in development stages and hence undergoing constant

changes. Details of the data import progress and some issues are summarized in the report

“SafetyAnalyst Data Import Progress and Issues”.

It should be noted that successful data import into SafetyAnalyst does not automatically

guarantee that all the data is useable by SafetyAnalyst until post processing and calibration

procedures are completed. Therefore, once the data has been successfully imported into

3

SafetyAnalyst, a detailed assessment of the post processing and calibration results were

conducted. The results were painstakingly verified manually and using a number of tools to

assess and evaluate the status of Wisconsin data. Detailed results are presented in the report

“Wisconsin Data Evaluation and Assessment for SafetyAnalyst Data Import, Post Processing,

and Calibration (First Dataset)”. In view of the data evaluation report, it was decided to request

a new second set of data after mutual discussions with WisDOT with changes to remedy some of

the shortcomings in the first dataset.

Once the second dataset had been received by TOPS lab, the data were again imported; post

processed, and calibrated using SafetyAnalyst. A second report was completed summarizing the

issues and status of the new dataset. Details of the data evaluation are presented in the report

“Wisconsin Data Evaluation and Assessment for SafetyAnalyst Data Import, Post Processing,

and Calibration (Second Dataset). Although there were some issues remaining with the dataset,

most of the major issues had been resolved and it was decided to proceed with the next steps of

the project in terms of evaluating the functions and modules of SafetyAnalyst.

The second part of the project included the detailed evaluation and assessment of SafetyAnalyst

modules, their functionalities and comparison with current WisDOT practices. The objectives

were to test the workings of SafetyAnalyst using Wisconsin data and evaluate the functions and

validate the SafetyAnalyst analysis output. Detailed analyses were conducted which are

presented in the following reports.

1. SafetyAnalyst Evaluation and Systems Requirements Assessment – Module 1 Network

Screening – Module 4 Evaluation of Implemented Countermeasures

2. SafetyAnalyst Evaluation and Systems Requirements Assessment – Module 3 Economic

Analysis

3. SafetyAnalyst Evaluation and Systems Requirements Assessment – Economic

Assessment of HSIP Applications Using SafetyAnalyst – Module 2 Diagnosis and

Countermeasure Selection.

Safety Analyst Analytical Tool includes 4 modules which includes a number of safety analysis

methods which are named below:

1. Network screening

2. Diagnosis and countermeasure selection

3. Economic appraisal and priority-ranking

4. Evaluation of implemented countermeasures

Module 1 helps users identify potential sites for safety improvements. The evaluation of this

module focused on a comparison between SafetyAnalyst results and the results of current

WisDOT 5% report for high crash locations. Part of the functions included in the screening tool

may possibly enhance the current WisDOT 5% reporting process and procedure. Detailed results

of the comparison are presented in the report “SafetyAnalyst Evaluation and Systems

Requirements Assessment – Module 1 Network Screening – Module 4 Evaluation of

Implemented Countermeasures”.

4

The evaluation of Module 4 focused on whether or not the tool can provide users with the ability

to conduct before/after evaluations of implemented safety improvement projects. Such

evaluations are highly desirable to increase knowledge of project effectiveness, especially the

ones applied in Wisconsin. Detailed results are presented in the report “SafetyAnalyst

Evaluation and Systems Requirements Assessment – Module 1 Network Screening – Module 4

Evaluation of Implemented Countermeasures”.

Evaluation of Module 3 and Module 2 are presented in the reports “SafetyAnalyst Evaluation

and Systems Requirements Assessment – Module 3 Economic Analysis” and “SafetyAnalyst

Evaluation and Systems Requirements Assessment – Economic Assessment of HSIP

Applications Using SafetyAnalyst – Module 2 Diagnosis and Countermeasure Selection”. The

evaluation results provide detailed analysis on the functions of SafetyAnalyst tools and

procedures and also show comparisons with current WisDOT HSIP evaluation procedures.

SafetyAnalyst Data Import Progress

and Issues

Ghazan Khan, Research Assistant

Steven Parker Ph.D.

Xiao Qin, Ph.D., P.E.

Traffic Operations and Safety (TOPS) Laboratory

March 5, 2009

2

DISCLAIMER

This research was funded by the Wisconsin Department of Transportation. The contents of this

report reflect the views of the authors who are responsible for the facts and accuracy of the data

presented herein. The contents do not necessarily reflect the official views of the Wisconsin

Department of Transportation at the time of publication.

This document is disseminated under the sponsorship of the Department of Transportation in the

interest of information exchange. The United States Government assumes no liability for its

contents or use thereof. This report does not constitute a standard, specification, or regulation.

The United States Government does not endorse products or manufacturers. Trade and

manufacturers’ names appear in this report only because they are considered essential to the

object of the document.

3

SAFETYANALYST DATA IMPORT PROGRESS

• Data for use in SafetyAnalyst was received from WisDOT in CSV file format to be imported

into SafetyAnalyst using the Data Management Tool.

• Detailed steps of the data import process into SafetyAnalyst are presented in Appendix B.

• Several options were explored as to how to setup the data import process in SafetyAnalyst as

the Data Management Tool provides more than one method to import data. It was decided to

use the Oracle based database to database import method using custom built XML based

Mapping Schema created in the SafetyAnalyst Data Management Tool. Data in CSV files

was loaded onto an input loader database called “SALDR” which would be placed in an

output production database “SAPRD” by the Data Management Tool using the custom built

XML Mapping Schema. The reasons for selecting this procedure are below:

a. To ensure that any changes in the input database would be reflected in the output

database easily and efficiently.

b. To provide ease in importing new data in the future which could automatically be

imported into SafetyAnalyst without further processing or changes.

c. To ensure database integrity and potential safeguard against risk of data loss in any

database.

d. To provide means to create custom views in the input database to fulfill data

requirements for fields for data was not available in the WisDOT provided CSV files.

• The next step involved the creation of XML Mapping Schema in the SafetyAnalyst Data

Management Tool. Creation of the mapping schema required the identification of data

elements required for the data import process as well as for the functioning of various

SafetyAnalyst modules. Critical data elements missing from the CSV files were identified

and a list of missing data elements was produced. Figure 1 below shows a typical view of

the XML Mapping Schema in SafetyAnalyst Data Management Tool with available data

elements shown in black and unavailable data elements shown in grey.

4

Figure 1 SafetyAnalyst XML Mapping Schema Typical View

• The missing data elements were obtained by creating custom views in Oracle database using

data from the CSV files and Wistransportal database such that it would ensure the availability

of the missing data elements in the proper type and format as required by SafetyAnalyst.

Figure 2 below shows some of the custom created database views in Oracle database.

5

Figure 2 Creating Customized Database Views for SafetyAnalyst Data Import

• In order to test the performance of the import process, an XML Mapping Schema of only the

data elements required for import of data was created. This testing of the import process

resulted in several errors which were discussed with the software developers. Some of these

errors were identified as critical software errors and bugs which were subsequently corrected

in newer versions of the software. The debugging process was an unexpected stumbling

point in the data import process which delayed the process by several weeks.

• Once the software glitches were removed and a test import was successful, efforts began to

create a full and final XML Mapping Schema to include all data elements available through

the CSV files and custom built database views created in Oracle. The final XML Mapping

Schema required substantial effort as all enumeration values for individual data elements had

to be manually checked for completeness and errors to ensure complete accuracy in the data

import process. However, as noted previously, the advantage of the database to database

import process is that this process has to be completed only once and any new data would be

just a few clicks away from being imported into SafetyAnalyst.

• After the completion of the final XML Mapping Schema, the data was successfully loaded

onto the output “SAPRD” database.

• The next step in the data import process required post processing of the data by

SafetyAnalyst. A number of errors were reported during the Post Processing. Some of these

errors were attributed to input data whereas others were attributed to software issues.

Continued discussions with the software developers resulted in the resolution of many of the

software related issues.

6

• A detailed analysis was conducted of the resulting SAPRD database and results were

generated for various analytical methods of the SafetyAnalyst software. The aim was to

identify errors and missing elements which could not be pin pointed during the initial data

import procedure.

• The analytical side of the software was also evaluated after importing the data into

SafetyAnalyst production tables (SAPRD Database Tables). The Analytical Tool modules

were run to perform safety analysis on intersection and road segments separately. Note that

no analysis was conducted for ramps because ramp data is not available at this point. A

report was generated outlining the performance of functions of each module, showing

potential issues with the results, and the number of invalid sites due to various reasons.

• Note that subsequent changes and improvements in the software in light of input from

various DOTs nationwide resulted in continuous improvements and changes in the software

which also resulted in continued changes in the input data format etc. resulting in further

delays in the overall implementation of the software. For example, the entire Module 4 of

the software has been changed which required a complete overhaul of SALDR database and

all the data had to be imported from scratch again.

• A comprehensive report was prepared including the status of all the data elements received,

working, non-working for various reasons, and missing elements which was shared with

Brad. Some of the missing data elements were not available in the WisDOT database

therefore, were dropped from the data import process. For the rest of the missing data

elements, Brad would provide as much information as possible.

Wisconsin Data Evaluation and

Assessment for SafetyAnalyst Data

Import, Post Processing, and

Calibration

First Dataset


Steven Parker Ph.D.



March 5, 2009

1

DISCLAIMER











2

SAFETYANALYST DATA IMPORT, POST PROCESSING, AND CALIBRATION

REPORT USING WISOCNSIN DATA

This document presents a summary of SafetyAnalyst implementation and evaluation status

which is being conducted by the Traffic Operations and Safety (TOPS) Lab. for the Wisconsin

Department of Transportation (WisDOT).

The sections below present a summary of the current status after data import, post processing,

and calibration were completed by SafetyAnalyst using the first set of Wisconsin data as

received by TOPS lab. from WisDOT. The first step of data import was conducted using the

Data Management Tool. This report also includes an initial evaluation and assessment of the

SafetyAnalyst Analytical Tool which conducts the actual safety data analysis. Each of the steps

are summarized below with details provided in the attached tables and flowcharts at the end of

the report.

SAFETYANALYST DATA MANAGEMENT TOOL

The first step in SafetyAnalyst implementation was the data import using SafetyAnalyst Data

Management Tool which has been completed. The process adopted for data import was selected

from a number of different options available in SafetyAnalyst. After extensive discussions and

research, it was decided to use a database to database import using SafetyAnalyst xml mapping

capabilities.

There were two major types of issues encountered during the data import process, namely

software issues and data issues. The data issues can be further subdivided into two types i.e.

missing data issues, data structure issues.

Software Issues

The software related issues are highlighted in Table 1 showing the problem encountered and how

it was resolved. Most of the software related issues occurred due to the fact that SafetyAnalyst is

still in development stages, and being one of the first states to implement SafetyAnalyst and the

database to database mapping data import process, TOPS lab. encountered most of the issues.

Data Issues

Data Structure Issues

Issues related to the structure of the data occurred because as mentioned before, SafetyAnalyst is

still under development and changes made to the software resulted in changes to the data

structure required for SafetyAnalyst. These changes meant that the CSV files generated by

WisDOT were not exactly to the specifications required by SafetyAnalyst. This problem was

resolved by creating database views in Oracle to conform the data to SafetyAnalyst required

structure. Details of these are presented in Table 1 and attached flowchart. Moreover, the

structure of each data element and any changes made to it are detailed in Table 2. It is

recommended that WisDOT along with TOPS lab. discuss the issues related to data structure so

3

that the effort required by WisDOT in generating the input CSV files in minimized. The aim is

to use the SafetyAnalyst internal mapping capabilities to directly import data from WisDOT

sources. For example, currently enumeration values for certain data elements are changed by

WisDOT to conform to SafetyAnalyst input values. Ideally, we would like to make those

changes in the SafetyAnalyst import map rather than during the generation of the input CSV files

at WisDOT. Furthermore, certain data structure issues have to be changed during the generation

of the CSV files by WisDOT such as the number of lanes data is required by SafetyAnalyst in

separate columns for each travel direction. Currently, this information is available only in one

column. Other such issues are detailed in Table 2. The aim is to facilitate the import of

WisDOT data into SafetyAnalyst with minimum changes made in the database views as shown

in the attached flowchart.

Missing Data Issues

There were some issues related to missing data elements which affects different aspects of

SafetyAnalyst operations. Some missing data elements created issues during the data import,

post processing, and calibration steps. Other missing data elements affected the performance of

the Analytical Tool and functions of the four SafetyAnalyst modules by invalidating sites with

missing data. If a site is invalidated due to missing data elements in SafetyAnalyst, analysis

cannot be performed on that site, although it remains part of the dataset. Details of these missing

data elements, their effects on the performance of SafetyAnalyst functions, and the causes of

invalid sites in SafetyAnalyst (Intersections and Road Segments) and their numbers are presented

in Table 2 and Table 3. Majority of the issues in intersections are related to missing or

incomplete Traffic Control information and minor road AADT values which are required for site

subtype assignments in SafetyAnalyst. The main causes of invalid road segments are missing

AADT data, median type, or access control information. Note that missing or incomplete AADT

information can also affect the calibration of Safety Performance Functions during the

calibration process of the SafetyAnalyst Data Management Tool.

SAFETYANALYST ANALYTICAL TOOL

The SafetyAnalyst analytical tool is the interface where the safety data analysis is conducted

using the four modules of SafetyAnalyst, namely, Network Screening, Diagnosis and

Countermeasure Selection, Economic Analysis, and Countermeasure Evaluation.

Once data was imported into SafetyAnalyst production tables (SAPRD Database Tables), the

Analytical Tool modules were run to perform safety analysis on intersection and road segments

separately. Note that no analysis was conducted for ramps because ramp data is not available at

this point.

The performance of each module for analyzing intersections and road segments is presented in

Table 4. The table indicates whether a particular function of each module is working or not

along with comments showing any potential issues with the results of the analysis due to data

issues as explained in the previous sections. Moreover, Table 3 also shows the number of invalid

sites (Intersections and Road Segments with no site subtype assignments due to various reasons)

which gives an idea about the breadth of the safety analysis given current data levels. Note that

4

module 4 has not been tested yet because significant changes are expected to the functions of this

module, hence, it will be evaluated once those changes are complete.

RESULTS

The results of the functions of each module in the Analytical Tool are provided with this report.

Some of the functions are specific to each site type and cannot be performed for both

Intersections and Road Segments. The results also show some inadequacies for example, the

output report for Network Screening of intersections shows the intersection ID as a bunch of

numbers which do not intuitively present the location of the intersection. Such issues have been

mentioned in Table 2 for each data element and how its format and structure would impact the

output of the Analytical Tool. Moreover, the results are based on current data levels and the

quality of results will improve as the missing information becomes available.

The basic results of the Analytical Tool and results of all the three working modules are attached

with this report. The analyses were performed for all the road segments and intersections in

Dane County separately.

Note that the analysis performed for evaluation purposes is test analysis and no effort was made

to collect additional details required outside of SafetyAnalyst to select the countermeasures for

ranked locations because this was outside the scope of this project.

S.

NoIssues / Errors

Fix

Complete/

Pending

Solution Details Comments and Recommendations

1CSV data can be imported using 5 different ways into

SafetyAnalystComplete Database to Database mapping using SA XML schema option

2SafetyAnalyst XML Mapping schema requires

identification of required elements in databaseComplete Required elements identified and verified for correctness and completeness

This was done to facilitate a trial run of SafetyAnalyst Data

Management Tool to assess the status of Wisconsin Data

3Significant differences in WisDOT CSV file data

structure and SafetyAnalyst required data structureComplete Database views in Oracle were constructed to match SafetyAnalyst required data structure

Some elements are in different structure or format than as

required by SafetyAnalyst due to subsequent changes in the

SafetyAnalyst data structure. More details can be found in

the individual data element evaluations

4 All Required missing data elements identified and fixed Complete Additional data included in Oracle database views from additional Wistransportal sources e.g. Accident database, etc.

Although all of the required data elements are now available

for SafetyAnalyst to work, other data elements are important

to improve the quality and ease of data analysis in

SafetyAnalyst

5 Test run of required data import in SafetyAnalyst

6

Program Error! Geodatamap: Duplicate geographic

description found for ID = ,,,,; Duplicate ID =

G006….

Complete Software Debugged

7Log file issues/No proper log made it difficult to

diagnose errorsComplete Software Debugged/Server timeout issue

Significantly delayed the process of data import because in

the absense of logs, it was difficult to pin point the problem

and issues

8Location System Issues: Elements of Location definition

were put in one fieldComplete Column split into Route Section Distance

9Split columns of Route Section Distance for the

Location System were not in required data typeComplete Distance value cast to number from string

10Distance value of Location System was in 1000th of

mileComplete Distance value divided by 1000

11Software Error! Data elements in mapping window did

not turn off when turned offComplete Software Debugged

12 Errors due to missing intersection leg information Complete SafetyAnalyst software people suggested to drop the use of leg information tables

13 Intersection leg and leg traffic data elements missing Complete Intersection Leg and Leg Traffic Tables were dropped from data import, Instead SafetyAnalyst generate leg information automatically

14 Required Elements data import complete

15 Non-required missing data elements identified and fixed Pending Some elements were calculated using Oracle database querries, others still missingDetails are provided in the individual data element

evaluation tables to be discussed with WisDOT

16 Data Import process complete - Begin Post Processing

17Post Processing invalidates all intersections (No reason

shown in the log file)Complete Software Debugged - Log file shows missing data elements and site subtype assignment not completed

18Post Processing removes all invalidated intersections

from the dataComplete Software Debugged - Invalided intersections and elements will remain in the dataset but not used in any analysis

19Post Processing identified more than 1 intersection with

exactly same locationPending

Intersections sharing location with other intersections were dropped from the dataset using Oracle database views, no fix has been

identified yet1132 Duplicate Intersections

20Segment Traffic year information available only for 2007

which is out of range for crash data (2001-2005)

21Error! Traffic Colume range needs to be larger or equal

to the range of crash data

22Major road Traffic year information available only for

2007 which is out of range for crash data (2001-2005)

23 Missing all Minor road traffic volume data PendingStatic value of 10 has been used for now because SafetyAnalyst does not accept 0 value - minor road traffic volume required element

for post processing

Discussion with MI DOT suggests to estimate minor road

AADT as a function of functional class, urban/rural

location, county population etc.

24 County information available only as county codes CompleteCounty names were joined to roadway segment and intersection data to provide "Names" during Analytical tool queries - Facilitates

easier querying of sites

25Missing data: Roadway segments missing county

informationPending Missing information in CSV files 40 Segments

26 Missing data: Intersections missing county information Pending Missing information in CSV files 19 Intersections

TABLE 1

Additional years of AADT information must be provided in

order to make the analysis more accurate. If there are

missing years of information, a growth factor could be

provided to facilitate interpolation of data between years to

cover missing years of AADT. The format of AADT and

Year information in based on 2 columns, with column

"AADT" providing the volume information and column

"YEAR" providing the corresponding year information.

Hence the column would grow in rows every year with

provision of new AADT data

Static value of 2002 was used to bring the available volume data (for both road segments and intersections) in range with crash data

thereby facilitating the use of SafetyAnalyst Analytical Tool, which previously did not work with out of range AADT data. The

software was debugged so that it could use out of range AADT data with crash data. Although this is not a desireable scenario to use

different years of AADT and crash data, the error had to be resolved. Note that SafetyAnalyst has the provision of interpolating or

Extrapolating AADT data provided a Growth Factor. If no Growth Factor is provided, SafetyAnalyst will calculate a Growth Factor

based on two extreme years of data and generate missing years data based on the calculated Growth Factor. Note also that when

SafetyAnalyst calculates the growth factor, there is a possibility that Growth Factor caculated by SafetyAnalyst might be too large if

there is a large increase in data or some error in AADT data for extreme years. In that case, there is work in progress right now to

generate a warning in the log file to indicate extreme Growth Rates say greater than 20%. There are also suggestions to provide the

user with option to indicate a threshold beyond which the log will give a warning.

Pending

SafetyAnalyst Implementation Timeline, List of Issues, and Program Errors, Comments and Recommendations

The provision for "Intersection Leg" and "Leg Traffic"

information in SafetyAnalyst was primarily for those

agencies which maintain intersection information by legs.

WisDOT generated CSV files contained this information

derived from various sources. Since WisDOT does not

specifically maintain intersection information by legs, it is

recommended that these tables be dropped from the CSV

files in the future

27 Missing data: Crashes missing county information Pending Missing information in CSV files 45 Crashes

28 Missing data: Roadway segments missing AADT Pending Missing information in CSV files 1113 Segments

29 Missing data: Major road segments missing AADT Pending Missing information in CSV files 1111 Leg Segments

30 Missing data: Crashes missing date information Pending Missing information in CSV files 39 Crashes

31Roadway segment invalidated - End location is greater

than start locationPending

Some segments have 0 length because the Start and End location values are exactly the same - These segments were dropped out from

Oracle Database views1816 Segments

32 Error! Intersections with no valid legs PendingNo information available, could be due to 0.5, 1.5 number of lane information for some segments that would result in this error but

not sure36 Intersections

33 Error! Crashes cannot be located on inventory elements Pending Possible reason could be that crashes occurred on removed segments and intersections 2166 Crashes

34

Error! Number of lane information issues - Lane info

required in separate columns for each direction but was

available as total number of thru lanes in one column

Pending

Undivided segments are represented by only one record which provides "Total number of lanes" for both directions while number of

lanes for each travel direction is required seperately. Total number of thru lanes column was divided by 2 to generate lane_dir1 and

lane_dir2 columns for undivided road segments. Dividing "Total number of thru lane" column into two resulted in some segments

with number of thru lanes in decimal e.g. 1.5, 2.5 etc. Divided and One-way road segments are represented by seperate data records

for each travel direction, therefore lane_dir1 = total number of lanes while lane_dir2 = 0. Modification to CSV file is required to

overcome this problem in the future

110 Segments with .5 lanes

35 Error! Incorrect traffic volume data Pending

Undivided segments are represented by only one record showing one travel direction only but AADT values provided are for both

travel directions. This works for undivided segments but not for divided segments. For now the AADT column was divided in half

for divided segments only but changes to CSV file required to correct this problem in future.

8168 Segments affected

36 Error! Lane width required for each travel direction PendingAverage Lane Width for undivided highways is incorrect. It was divided by "Total number of lanes" to correct it. For Divided and

One-way segments, the values were ok. CSV files need to be modified to correct this issue.

37 Error! Intersections Invalidated Pending Site Subtype assignment required traffic signal control information which is missing for most of intersections

20900 Intersections affected - Discussions with MI DOT

and OH DOT suggests making assumptions about traffic

control such as majority of them would be either two-way

stop control or flasher

38Error! Incorrect Site Subtype assigned to One-Way

segmentsComplete Software Debugged

39Many site subtype assignments require median

information for road segmentsPending

CSV code shows that median information for undivided segments and segments with unknown medians are both assigned '99'

(unknown) while SafetyAnalyst requires median type value of '0' for undivided segments. CSV files may need modification to separate

unknown median type from known median type information for undivided segments.

40

Error! Mapping enumeration values for various data

elements (SA code changed to require 1,2,3... instead of

01,02…

Pending

The code for following elements should be corrected in CSV files. Junction Relationship, Weather Condition, Surface Condition,

Vehicle Configuration 1, Vehicle Configuration 2, First Event 1, First Event 2, Median Type Level 1, Roadway Class 1. Once CSV

code is changed, remove the mapped values from SafetyAnalyst XML map.

41Missing data: Accident Severity 1, CSV code shows no

details on injury types A,B,C etc.Pending

Injury information available from CSV files and Wistransportal Crash Database are both incomplete. Possible solution could be to

join the two columns or modify CSV files to include the breakdown of injury severity in terms of A,B,C

42

Missing data: Shoulder type Out and In, Direction 1 and

Direction 2, 4 data elements needed. CSV files have

Shoulder Type Out and In, no direction info

PendingShoulder Type Inside and Outside info required for each direction of travel. CSV code needs modification. Note that this data might

be correct for divided segments but not for undivided segments

43

Missing data: Shoulder Width Out and In, Direction 1

and Direction 2, 4 data elements required. CSV contains

only Avg Shoulder Width In and Out, no direction info

PendingShoulder Width Inside and Outside info required for each direction of travel. CSV code needs modification. Note that this data might

be correct for divided segments but not for undivided segments

44Error! CSV file Step 2 "Informat Travel Direction" code

has last line as operationway = 'X'Pending This should be changed to Traveldirection = 'X'

45Error! Database query list generation error due to

modifications in SafetyAnalyst codeComplete

During post processing, there was an error during generating query lists for SafetyAnalyst. The errors were due to changes in core

SafetyAnalyst code. This was resolved by reproducing the query tables in Oracle database

46Post processing completed - Each column of each table

was manually checked for correctionsComplete Took a very long time

47 Data Calibration Process Pending

The calibration process calibrates the Safety Performance Functions for Wisconsin data. Default parameters have been used for now

in the calibration process but this is something which will change as missing data elements are included in the dataset and the choice of

parameters could be changed based on engineering judgements

The missing AADT information is also criticle for proper

calibration of Safety Performance Functions

48 SafetyAnalyst Analytical Tool Run CompleteThe Analytical Tool and the first 3 modules work - Module 4 does not work yet. The results of the Analytical Tool will improve when

missing data elements are filled and abovementioned issues are resolved

Details of the performance of each Module are provided in

the Analytical Tool Functions Evaluation report

49 Implemented Countermeasure Tool Evaluation Pending

Although the Implemented Countermeasure tool, which is a bridge between Module 3 and Module 4 works, There is still work under

progress to be able to include Project Cost information in this tool for calculations of Benefit Cost ratios for evaluation of completed

projects (Important for HSIP evaluations)

Evaluation will be completed after all the modifications have

been completed by SafetyAnalyst developers

50 Module 4 (Countermeasure Evaluation) Evaluation PendingModule 4 which is countermeasure evaluation module is not working at the time. There are also some modifications in progress for

this tool to include Benefit Cost Ratio calculations in this tool to be used primarily for HSIP evaluations

Evaluation will be completed after all the modifications have

been completed by SafetyAnalyst developers

51 Homogenous Segments Issue Pending

There is option available to generate homogeneous segments from input dataset because generally, smaller length segments tend to

scew the results because of larger crash rates. This is a technical issue which needs further discussion with WisDOT and Safety

Engineers before a decision is reached

Creation of Homogeneous segments is not a requirement

for SafetyAnalyst to work but could be important given the

average segment length which stands at 0.92 at the time.

This can offcourse change as missing data elements are

completed and comparison made with other states in terms

of their average segment lenghts

*All functions of SafetyAnalyst are operational at this point (Except Module 4 which is undergoing some changes)

**The pending items in this document only affect the quality and breadth of the results but not the operation of SafetyAnalyst

Status

SafetyAnalyst Import Map

Element Name (Roadway

Segment)

Usage 1

Data Element Column

Name in SALDR Loader

Database View

(SafetyAnalyst XML

Map Name)

Status (Available Not

Available, Modified)Issues Issue Explaination and Possible Solutions Data Element Evaluation and Suggestions Update

Segment ID Required segmentid Available No

There are some segments where the 'Distance" part of location There are 1816 out of 20615 segments which SafetyAnalyst assumes

TABLE 2

SALDR Loader Database View Data Elements Description - (SALDR.V_DATASET_ROADWAYSEGMENT_FINAL)

SafetyAnalyst Data Elements Table Showing Status, Issues, Solutions, Suggestions, Recommendations, Evaluation, and Effects of Each Data Elements on SafetyAnalyst Analysis

Performance

SafetyAnalyst Information

SAPRD Production Database and SafetyAnalyst Import

Map Data Elements Description - (AltRoadwaySegment -

Roadway Segment)

WisDOT Information

Location System RequiredStatic Value

(Route/Section/Distance)Available Yes

There are some segments where the 'Distance" part of location

is the same for start and end. This means these segments have 0

length which is a problem. Location column in

saldr.dataset_intersection was split into Route, Section, Distance

columns column names of which are presented below

There are 1816 out of 20615 segments which SafetyAnalyst assumes

to have length of 0 and invalidates them. These segments will not

be included in the analysis and create accuracy issues in statewide

Network Screening analysis.

Fixed

Route Type Required routetype Available No

Route Name Required routename Available No

CountyConditionally

requiredcnty_name Available No

saldr.dataset_roadwaysegment "county" column with county

codes was used to join "cnty_name" column from

couties.cntycodes to provide county names rather than code

values

Include county names instead of codes in the "county" column

Unfixed. In table

Dataset_geographicdesc

ription, change the

attribute "county" to

"cntycode"

Start of Segment SectionConditionally

requiredstrt_loc_section Available No

saldr.dataset_roadwaysegment "Location" column was split to

create this column

Unfixed. In table

Dataset_roadwaysegme

nt, split the "location"

column.

Start of Segment Offset Required strt_loc_distance Available Nosaldr.dataset_roadwaysegment "Location" column was split, cast

to number, and divided by 1000 to create this column

Unfixed. In table


nt, split the "location"

column.

End of Segment SectionConditionally

requiredend_loc_section Available No

saldr.dataset_roadwaysegment "End_C" column was split to

create this column

Unfixed. In table


nt, split the "end_c"

column.

End of Segment Offset Required end_loc_distance Available Nosaldr.dataset_roadwaysegment "End_C" column was split, cast

to number, and divided by 1000 to create this column

Unfixed. In table


nt, split the "end_c"

column.

Agency Site Subtype Considered Not Available Column missing

Although not required, if WisDOT has certain site subtype

classifications for which it has SPF's generated, then this column

could be used

Unchanged.

GIS Identifier - Starting

LocationGIS interface geographicid Available No

Alternate Route Names Display alternateroutename Available No

"Routedisplayname" column in saldr.dataset_roadwaysegment is

empty. "routename" column was pulled as "alternateroutename"

from saldr.dataset_alternateroutename to be used in

SafetyAnalyst

Unchanged. All

alternateroutenames are

same as routenames, but

they are supposed to

provide alternate route

numbers for concurrent

highways.

Major Road Name Display Not Available Column available but missing values

Used when a roadway has both numbered route and road name.

The road name is input here. Very useful to identify the segment in

SafetyAnalyst Analytical Tool tables views

Unchanged.

Segment Length Required segmentlength Available No

57 out of 21023 of these

values don't match the

difference of "Start

offset" and "End

offset".

District Query district Available No

"district" column with district codes was pulled from

saldr.dataset_geographicdescription because

saldr.dataset_roadwaysegment did not have this column.

Include district names instead of codes in

saldr.dataset_geographicdescription which would make data query

in SafetyAnalyst Analytical tool much easier

Unchanged.

City/Town Query Not AvailableColumn available in saldr.dataset_geographicdescription but

missing values

If available, this information would make data query in

SafetyAnalyst Analytical Tool more flexibleUnchanged.

Jurisdiction Query Not AvailableColumn available in saldr.dataset_geographicdescription but

missing values


SafetyAnalyst Analytical Tool more flexibleUnchanged.

Area Type Required areatype Available No"areatype" column was pulled from

saldr.dataset_geographicdescription

Terrain Considered Not Available column is available but all filled with 'X' values

If available, would facilitate creation of homogeneous segments

which would improve analysis results because very small segment

size could skew some SafetyAnalyst statistical results

Unchanged.

Roadway Class Level 1 Required roadwayclass1 Available Yes

CSV files have enumeration values as 01, 02,…. These should be

changed to 1,2,3….. For consistency. Otherwise 01,02,03..

Mapped values have to be provided in SafetyAnalyst XML map

for data import

1725 out of 20615 segments have unknown road class value. These

sites would not considered for analysis in SafetyAnalyst Analytical

Tool and could reduce the accuracy of statewide analysis results

Format fixed. 1705 out

of 21023 segments have

unkown road class.

Number of Through Lanes -

Direction 1Required lanes_dir1 Available Fixed

saldr.dataset_roadwaysegment provides "numthrulanetotal" as

total number of lanes for each road segment in one column.

SafetyAnalyst requires number of lanes for each direction

seperately. We created two new columns, lanes_dir1 and

lanes_dir2. For divided and one-way segments, we set lanes_dir1

Provide two separate columns instead of one for number of lanes

for each direction. For undivided highways, provide number of

lane information for each direction seperately in these columns.

This would require modifications to the code which generates the Yes

Number of Through Lanes -

Direction 2Required lanes_dir2 Available Fixed

Auxiliary Lane 1 - Direction Module 3

Auxiliary Lane 2 - Direction

1Module 3


1Module 3


2Module 3


2Module 3


2Module 3

Lane Width - Direction 1 AMFs lane_width1 Available Fixed


lanes_dir2. For divided and one-way segments, we set lanes_dir1

= numthrulanetotal. For undivided highways we set lanes_dir1

and lanes_dir2 = numthrulanetotal/2. This creates problems

when "numthrulanetotal" is odd number.

This would require modifications to the code which generates the

CSV files. This is critical especially when number of lanes in both

directions are not the same.

Yes

Yes

Although saldr.dataset_auxiliarylane has auxiliary lane type

information available, SafetyAnalyst requires this information

for each direction of travel seperately. For divided and one-way

segments it is ok, but for undivided segments, only 1 value is

provided which we are not sure corresponds to auxiliary lane

type of which direction. Also the enumeration values are

01,02,03 format which should be changed to 1,2,... format.

Two separate columns should be created to provide lane width

information for each direction of travel, especially for undivided

segments. CSV codes need to be modified for this purpose. This

information is critical for accurate Economic Apprailsal of projects

in Module 3 of SafetyAnalyst. Note: 28 segments have lane width =

0 which means these may not be included in the analysis

This information is critical for Economic Appraisal of construction

projects in Module 3 of SafetyAnalyst. The CSV file codes should

be modified to provide the Auxiliary lane type information for each

direction of travel seperately in individual columns by direction.

For divided segments and one-way roads, the auxiliary lane code

for direction 2 would be '0' indicating no auxiliary lane because in

cases of divided and one-way road segments, each direction of

travel is represented by different data record. CSV code should be

modified to change enumeration values from 01,02... to 1,2.. format

"avglanewidth" column is provided in saldr.dataset_directional.

This column corresponds to average lane width while

SafetyAnalyst requires lane width information for each direction

of travel separate in two columns. For now, the column was split

into two and value divided by number of lanes for undivided

highways to get lane width information for each travel direction.

For divided and one-way segments, lane_width1 = avglanewidth

while lane_width2 = 0.

Yes

Not Available

Fixed. However, only 3

auxiliary lanes in each

direction are allowed in

SafetyAnalyst, but 6 are

provided in the table

Dataset_auxiliarylane.


Median Type Level 1 Required mediantype1 Available Yes

For undivided segments, SafetyAnalyst requires mediantype1 =

0. CSV files show that for undivided segments and segments

with unknown median are assigned value = 99. Enumeration

values for median types are provided as 01,02,… which should

be changed to 1,2,.. format. Many missing records

This information is absolutely critical for site subtype assignment.

Without this info, sites will be left out of analysis. CSV codes

should be modified to resolve the median type for undivided

highways and enumeration values issues. 4773 out of 8741 divided

segments have no median information which invalidates these

segments and removes them from analysis affecting the accuracy of

statewide results of Network Screening.

Format fixed. 5040 out

of 21023 segments have

unkown median type.

Median Width Considered medianwidth Available No

Shoulder Type - Outside -

Direction 1AMFs shouldertypeout Fixed

Shoulder Type - Inside -

Direction 1AMFs shouldertypein Fixed

Shoulder Type - Outside -

Direction 2AMFs shouldertypeout Fixed

Shoulder Type - Inside -

Direction 2AMFs shouldertypein Fixed

Shoulder Width - Outside -

Direction 1AMFs avgshoulderwidthin Fixed

Shoulder Width - Inside -

Direction 1AMFs avgshoulderwidthout Fixed

Shoulder Width - Outside -

Available Yes

This information was pulled from saldr.dataset_directional

where it is available in two columns, type in and type out.

SafetyAnalyst requires shoulder type in and type out for both

directions of travel seperately in columnds by travel direction.

For now, we are assigning both directions of travel the same

sholder type in and out.

This information was pulled from saldr.dataset_directional

where it is available in two columns, average width in and

average width out. SafetyAnalyst requires average width in and

out, for both directions of travel seperately in columnds by

The CSV codes should be modified to provide separate columns

for each travel direction and shoulder width which means 4

The CSV codes should be modified to provide separate columns

for each travel direction and shoulder type which means 4 columns

in total.

Available YesShoulder Width - Outside -

Direction 2AMFs avgshoulderwidthin Fixed

out, for both directions of travel seperately in columnds by

travel direction. For now, we are assigning both directions of

travel the same shoulder width by using the same column twice

for each travel direction and shoulder width which means 4

columns in total.

Available Yes

Shoulder Width - Inside -

Direction 2AMFs avgshoulderwidthout Fixed

Access Control Considered accesscontrol Available No

1728 segments have no access control information availability of

which would improve analysis results because very small segment

size could skew some SafetyAnalyst statistical results

Fixed

Driveway Density Considered Not Available Column available but missing values

Used in homogeneous segment creation which would improve

analysis results because very small segment size could skew some

SafetyAnalyst statistical results

Unchanged

Growth Factor Considered Not AvailableColumn available but missing values. For now we are using static

value of 1

This could be very important in calculating missing years traffic

volume data as SafetyAnalyst can interpolate or extrapolate missing

AADT values based on other years traffic volumes and growth

factor values

Fixed

Speed Limit Available No 688 segments with missing posted speed limit values Unchanged

travel the same shoulder width by using the same column twice

Two-Way vs. One-Way

OperationRequired operationway Available No 30 segments with missing values Fixed

Direction of Travel traveldirection Available No

Direction of Increasing

Mileposts or Distancesincreasingmileposts Available No

Bikeway - Direction 1 AMFs Not Available

Bikeway - Direction 2 AMFs Not Available

Interchange Influence Area

on Mainline FreewayRequired Not Available Yes Column available but missing values

This absolutely important for some site subtype assignments.

Without this some segments will be invalidated and left out of

SafetyAnalyst Analytical Tool analysis

Fixed

Date Opened to Traffic Not Available Column available but missing values

Discontinuity Not Available Column available but missing values

Corridor Module 1 corridor Available No80 missing values. Provide a description of what each code means

for corridor e.g. BB, C2 etc.

Comment Display Not Available Column available but missing values

Status


Element Name (Segment

Traffic)

Usage 1

Data Element Column


Database View

(SafetyAnalyst XML

Map Name)

Status (Available, Not

Available, Needs

Modification)

Issues Issue Explaination and Possible Solutions Data Element Evaluation and Suggestions Update

SALDR Loader Database View Data Elements Description - (SALDR.V_DATASET_SEGMENTTRAFFIC_FINAL)

WisDOT InformationSafetyAnalyst Information


Map Data Elements Description - (AltSegmentTraffic -

Segment Traffic)

Associated Agency Segment

IdentifierRequired segmentid Available No

Year Required Available Yes

saldr.dataset_segmenttraffic provides only 1 column

"calenderyear" for 2007. Ideally SafetyAnalyst should be

provided atleast 2 years of volume data and other missing years

data can be interpolated by SafetyAnalyst. For now we use the

2007 data which means that SafetyAnalyst will assume the same

AADT value for all other years in the absense of a "Growth

Factor" value

Need to provide additional years of AADT data which will all be in

one column along with the corresponding year information this

this column.

Growth Factor

provided.

AADT Required adt Available Yes

saldr.dataset_segmenttraffic has column "AADT" which

provides traffic volume sum of both direction for divided

segments which only represent one direction of travel. For now

we split this volume 50/50 for divided segments and use the

column "adt". There are also 1113 segments with missing values.

CSV codes need to be changed to generate only one direction

traffic volumes for divided segments. There are 1113 segments with

missing values. These segments will be invalidated and will not be

used in SafetyAnalyst analysis. 1113 Segments have no AADT

values

Heavy Vehicles percentheavyvehicles Available No 1123 missing values

Peak or Design Volume Not Available Column available but missing values


Status


Element Name

(Intersection)

Usage 1

Data Element Column


Database View

(SafetyAnalyst XML

Map Name)


Available, Needs

Modification)

Issues Issue Explaination and Possible Solutions Data Element Evaluation and Suggestions

SALDR Loader Database View Data Elements Description - (SALDR.V_DATASET_INTERSECTION_FINAL2)



Map Data Elements Description - (AltIntersection -

Intersection)

WisDOT Information

Intersection ID Required intersectionid Available No

Maybe use a better intersection ID to readily identify the result

location in SafetyAnalyst Analytical tool because the results

includes I100202|02322 values which do not readily identify the

location of the intersection. This ID ia based on the segments

Unchanged

Location System Requiredstatic value

(Route/Section/DistanceAvailable Yes

There are some intersections where the Distance part of the

location system is the same as other intersections. This means

these intersections lie at exactly the same spot as the other which

is offcourse wrong. Location column in

saldr.dataset_intersection was split into Route, Section, Distance

columns column names of which are presented below

There are 1132 out of 23481 intersections which have duplicate

locations. These intersections will not be included in the analysis

and create accuracy issues in statewide Network Screening analysis.

Changed


Route Name Required routename Available No

Note: We are using geographicid and routename, routetype

information from saldr.dataset_geographicdescription which

primarily identifies segments rather than intersections

CountyConditionally


saldr.dataset_intersection "county" column with county codes

was used to join "cnty_name" column from couties.cntycodes to

provide county names rather than code values

Include county names instead of codes in the "county" column Unchanged

Major Road SectionConditionally

requiredloc_section Available No

saldr.dataset_intersection "Location" column was split to create

this column

Major Road Offset Required loc_distance Available Nosaldr.dataset_intersection "Location" column was split, cast to

number, and divided by 1000 to create this column

Minor Road Location

SystemNot Available

Although minor road location information is not available, either

SafetyAnalyst gets this info from "Intersection leg" information or

generates the legs automatically

Unchanged

Minor Road Route Type Not Available

Minor Road Route Name Not Available YesAbsolutely needed for identification of the intersections in

SafetyAnalyst Analytical ToolChanged

Minor Road Section Not Available

Minor Road Offset Not Available

Agency Site Subtype Considered Not Available Column missing

Although not required, if WisDOT has certain site subtype

classifications for which it has SPF's generated, then this column

could be used

GIS Identifier GIS interface geographicid Available No




Alternate Route Names Display alternateroutename Available No

"Routedisplayname" column in saldr.dataset_intersection is

empty. "routename" column was pulled as "alternateroutename"

from saldr.dataset_alternateroutename to be used in

SafetyAnalyst




Major Road Name Display Not Available Column missing

Used when a intersection major roadway has both numbered route

and road name. The road name is input here. Very useful to

identify the major road of the intersection in SafetyAnalyst

Analytical Tool table views

Minor Road Name Not Available Column available but missing values

Used when a intersection minor roadway has both numbered route

and road name. The road name is input here. Very useful to

identify the minor road of the intersection in SafetyAnalyst

Analytical Tool table views

Major Road Direction majorroaddirection Available No

Beginning Influence Zone -

Major Road

Beginning Influence Zone -

Minor Road

End Influence Zone - Major

Road

End Influence Zone - Minor

Road

District Query district Available No

"district" column with district codes was pulled from

saldr.dataset_geographicdescription because

saldr.dataset_intersection did not have this column.

Include district names instead of codes in

saldr.dataset_geographicdescription which would make data query

in SafetyAnalyst Analytical tool much easier

Not Available Columns available but missing values

City/Town Query Not AvailableColumn available in saldr.dataset_geographicdescription but

missing values


SafetyAnalyst Analytical Tool more flexible

Jurisdiction Query Not AvailableColumn available in saldr.dataset_geographicdescription but

missing values


SafetyAnalyst Analytical Tool more flexible

Area Type Required areatype Available No"areatype" column was pulled from

saldr.dataset_geographicdescription

Intersection Type Level 1 Required intersectiontype1 Available No 7 intersections have unknown type values Fixed

Traffic Control Type at

Intersection Level 1Required trafficcontrol1 Available Yes

Only "Other Signalized" and "Other Non-Signalized"

information available. SafetyAnalyst requires exact details for all

traffic control types for site subtype assignment without which

the intersection become invalid. The enumeration values used

are "SI" and "XX" which if changed to SafetyAnalyst number

enumeration values would be better.

1379 Signalized intersections are assigned site subtype valie. 20970

Intersections are invalidated because of lack of traffic control

information. This is absolutely critical without which no

Intersection analysis can be performed in SafetyAnalyst. Total

number of intersections is 22349

Unchanged

Offset Intersection Not Available Column available but missing values

Offset Distance Not Available Column available but missing values

Growth Factor Considered Not Available Column available but missing values

This could be very important in calculating missing years traffic

volume data as SafetyAnalyst can interpolate or extrapolate missing

AADT values based on other years traffic volumes and growth

factor values

Fixed

Date Opened to Traffic Not Available Column available but missing values

Corridor Module 1 corridor Available No80 missing values. Provide a description of what each code means

for corridor e.g. BB, C2 etc.


Status

SALDR Loader Database View Data Elements Description - (SALDR.DATASET_MAJORROADTRAFFIC)


Map Data Elements Description - (AltMajorRoadTraffic -

Major Road Traffic)

SafetyAnalyst Information WisDOT Information


Element Name (Major

Road Traffic)

Usage 1

Data Element Column


Database View

(SafetyAnalyst XML

Map Name)


Available, Needs

Modification)


Associated Agency

Intersection IdentifierRequired intersectionid Available No


saldr.dataset_majorroadtraffic provides only 1 column






Factor" value


one column (aadtvpd) along with the corresponding year

information this this column.

Growth factor

provided.

AADT Required aadtvpd Available Yes

It seems that saldr.dataset_majorroadtraffic "aadtvpd" column

was generated using the data from saldr.dataset_segmenttraffic

because the numbers match. This means this dataset has the

same issues as with saldr.dataset_segmenttraffic where divided

segments aadt values are sum of both directions, which should

be recalculated only for one direction of travel. There are also

missing values of aadt.

There are 1111 mojor road segments with missing aadt values.

Intersections which consist of these major roads will be invalidated

and dropped from analysis in SafetyAnalyst. Also CSV codes need

to be changed to generate only one direction traffic volumes for

divided segments.

missing values of aadt.

Comment Display Not Available

Status


Element Name (Minor

Road Traffic)

Usage 1

Data Element Column


Database View

(SafetyAnalyst XML

Map Name)


Available, Needs

Modification)


Associated Agency

Intersection IdentifierRequired intersectionid Available No

SALDR Loader Database View Data Elements Description - (SALDR.DATASET_MINORROADTRAFFIC



Map Data Elements Description - (AltMinorRoadTraffic -

Minor Road Traffic)

WisDOT Information


saldr.dataset_minorroadtraffic provides only 1 column






Factor" value


one column (aadtvpd) along with the corresponding year

information this this column.

AADT Required static value (10) Not Available YesThis data is not available. For now we use static value od 10

because 0 does not work.

All minor road traffic volumes are missing which is critical.

Without minor road traffic volumes, SafetyAnalyst cannot analyze

intersections and all intersections are invalidated.

Unfixed. The constant

value 1000 is used as

minor AADT.

Comment Display Not Available

SALDR Loader Database View Data Elements Description - (SALDR.V_DATASET_ACCIDENT_FINAL)


Map Data Elements Description - (AltAccident -

Accident)

Status


Element Name (Accident)Usage 1

Data Element Column


Database View

(SafetyAnalyst XML

Map Name)


Available, Needs

Modification)


Accident ID Required accidentid Available No

Location System Requiredstatic value

(Route/Section/DistanceAvailable No

"Location" column in saldr.dataset_accident was split into

Route, Section, Distance columns column names of which are

presented below

Note: 2166 crashes cannot be located on inventory elements. Most

probably the reason behind this is the invalidated road segments

and intersections due to abovementioned deficiencies


saldr.dataset_accident does not have route type information so it

is pulled from saldr.dataset_geographicdescription based on

"geographicID' column which is common to both tables

SafetyAnalyst Information WisDOT Information

Route Name Required loc_route Available NoRoute name is collected by splitting the "Location" column in

saldr.dataset_accident which contains the route name

CountyConditionally


saldr.dataset_accident "county" column with county codes was

used to join "cnty_name" column from couties.cntycodes to

provide county names rather than code values

NOTE: 45 Crashes have no county information so they are

removed from the dataset. Include county names instead of codes

in the "county" column. This would make query analysis in

SafetyAnalyst Analytical tool much easier.

Accident Location SectionConditionally

requiredloc_section Available No

saldr.dataset_accident "Location" column was split to create this

column

Accident Offset Required loc_distance Available Nosaldr.dataset_accident "Location" column was split, cast to

number, and divided by 1000 to create this column

GIS Identifier GIS interface geographicid Available No

Agency Segment Identifier Considered Not Available

Agency Intersection

IdentifierConsidered Not Available

Agency Ramp Identifier Considered Not Available

Accident Date Required accidentdate Available No39 crashes have no date information. They are removed from the

dataset

Accident TimeAccident

Summaryaccidenttime Available No

Accident Severity Level 1 Required Available Yes

The CSV files have injury severity information as Fatal, Injury,

and PDO with no breakdown of Injury Severity. The crash

database from Wistransportal has injury severity information

(K,A,B,C) but no PDO indication (Empty row). For now, we

are using the injury severity column from the CSV files which

means no breakdown of injury severity.

Ideally, the CSV files should be modified so as to include the

breakdown of injury severity in terms of A,B,C. If not, we could

combine the injury severity columns from CSV files generated by

WisDOT with injury severity column from the Wistransportal

crash database to complete this information

Fixed.

Number of Fatalities Required totfatl Available No

saldr.dataset_accident has no number of fatalities. This data was

pulled from crash.v_combined from Wistransportal Crash

Database

Number of Non-Fatal

InjuriesRequired totinj Available No

saldr.dataset_accident has no number of injuries. This data was

pulled from crash.v_combined from Wistransportal Crash

Database

Relationship to Junction Required junctionrelationship Available No




for data import

Change CSV code to generate enumeration values in the 1,2,3….

Format as compared to 01,02,03…. Format

Driveway IndicatorAccident

SummaryNot Available Column available but missing values

Light ConditionAccident

Summarylightcondition Available No

Weather ConditionAccident

Summaryweathercondition Available No




for data import



Roadway Surface ConditionAccident

Summarysurfacecondition Available No




for data import



Accident Type and Manner

of CollisionRequired collisiontype Available No

Contributing Circumstances,

Environment

Accident


Contributing Circumstances,

Road

Accident


School Bus RelatedAccident

Summaryschoolbus Available No

Work Zone RelatedAccident

Summaryworkzone Available No

Number of Vehicles

InvolvedRequired numvehicles Available No

Alcohol/Drug InvolvementAccident

Summarydruginvolved Available No

Tow-Away IndicatorAccident


Run-Off Road IndicatorAccident


Pedestrian IndicatorAccident

Summarypedestrianindicator Available No

Bicycle IndicatorAccident

Summarybikeindicator Available No

Divided Highway Flag-Side

of Roadsideofdividedhighway Available No

Initial Direction of Travel -

Vehicle 1Required traveldirection1

Unchanged

Initial Direction of Travel -

Vehicle 2Required traveldirection2

Unchanged

Available

saldr.dataset_vehicleaccidentdata has information on travel

direction. This data is stored in rows representing each vehicle

of a crash. SafetyAnalyst requires travel direction for veh 1 and

veh 2 to be in seperate columns. Supplementary database view

was created called saldr.v_accdt_initialtraveldirection which

stored travel direction information in columns.

Note that while converting saldr.dataset_vehicleaccidentdata data

from rows into column, only 1st and 2nd vehicle data was

converted to columns as SafetyAnalyst has provisions for first two

vehicles of a crash. If more than 2 vehicles were involved in a

crash, information on those extra vehicles is not being used here.

Yes

Vehicle Maneuver/Action -

Vehicle 1Required vehmaneuver1

Vehicle Maneuver/Action -

Vehicle 2Required vehmaneuver2

Vehicle Configuration -

Vehicle 1

Accident

Summaryvehicleconfig1

Vehicle Configuration -

Vehicle 2

Accident

Summaryvehicleconfig2

Available Yes

saldr.dataset_vehicleaccidentdata has information on vehicle

maneuver. This data is stored in rows representing each vehicle

of a crash. SafetyAnalyst requires vehicle maneuver for veh 1

and veh 2 to be in seperate columns. Supplementary database

view was created called saldr.v_accdt_vehiclemaneuver which

stored vehicle maneuver information in columns.






Also the CSV codes should be modified to change the enumeration

values from 01,02,.... to 1,2,3... format

Available Yes

saldr.dataset_vehicleaccidentdata has information on vehicle

configuration. This data is stored in rows representing each

vehicle of a crash. SafetyAnalyst requires vehicle configuration

for veh 1 and veh 2 to be in seperate columns. Supplementary

database view was created called saldr.v_accdt_vehicleconfig

which stored vehicle configuration information in columns.








First Harmful Event -

Vehicle 1

Accident

Summaryfirstevent1

First Harmful Event -

Vehicle 2

Accident

Summaryfirstevent2

Driver Date of Birth -

Vehicle 1

Accident

Summarydriverdob1

Driver Date of Birth -

Vehicle 2

Accident

Summarydriverdob2

Available Yes

saldr.dataset_vehicleaccidentdata has information on first event

of a crash. This data is stored in rows representing each vehicle

of a crash. SafetyAnalyst requires first event of crash for veh 1

and veh 2 to be in seperate columns. Supplementary database

view was created called saldr.v_accdt_firstevent which stored

crash first event information in columns.








saldr.dataset_vehicleaccidentdata has information on driver

DOB of a crash. This data is stored in rows representing each

vehicle of a crash. SafetyAnalyst requires the driver DOB of

crash for veh 1 and veh 2 to be in seperate columns.

Supplementary database view was created called

saldr.v_accdt_driverdob which stored driver DOB information

in columns.

Red rows represent those data elements that are either missing or incomplete and which have an effect on accuracy or comprehensiveness of data analysis results

Yellow rows represent those data elements which could be modified to improve the performance or efficiency of data import and/or analysis process








Available Yes

Ramp and Ramp Traffic data is not available so those tables are not being used

Yellow rows represent those data elements which could be modified to improve the performance or efficiency of data import and/or analysis process

Intersection Leg and Leg Traffic Data is not being used. These tables are for those agencies that maintain separate leg information

This spreadsheet includes the data usage by element/attribute (table/column) names for the import data structures for all SafetyAnalyst import data

This spreadsheet also includes the name of the mapped column from SALDR views used to assign data.

This spreadsheet also includes the status of the data element, any issues, explaination and proposed solutions

Element Total Number Available for Analysis %age of Total Dataset

Roadway Segments 20575 13374 65.00

Ramps 0 0 0.00

Intersections 22330 1284 5.75

Accidents 252322 250155 99.14

Element Total Invalid Comments

Roadway Segments 20575 7201

1096 missing AADT, 13 missing number of lanes, 1816 with zero length,

2448 missing Access or Median info, 1828 missing Interchange Influence

data: Total = 7201

Ramps 0 0 No Ramp information is available

Intersections 22330 21046

20929 Intersections have site subtype assignment issues related to missing

Traffic Control information and missing minor road AADT, 117

intersections have misc missing data

Accidents 252322 2167These accidents cannot be located on the inventory. Probable causes

could be segments with 0 lengths, misc missing information

Data Element Type Missing Data Number of Missing Data Comment

Roadway Segments County 39

Segment Traffic Traffic Volume (aadtvpd) 1113 These are major road segments with missing volume data

Major Road Traffic Traffic Volume (aadtvpd) 1111

This value is similar to missing roadway segment number (segment traffic)

because intersections legs are part of the roadway segments dataset, hence

any missing information in the roadway segment dataset would lead to

missing information for the intersection legs

Intersections County 19

Accidents County 45

Accidents Accident Date 37

Missing Data Number of Missing Data Comment

Roadway Segments Traffic Volume (aadtvpd) 1096 Required for any type of analysis.

Roadway Segments Site Subtype assignment 4276

SafetyAnalyst could not assign a site subtype value. Possible reasons

include missing Median Type, Access Control, or Interchange Influence

Area values. 2448 missing Access or Median info, 1828 missing

Interchange Influence

Roadway Segments Number of Lanes 13 Required for any type of analysis.

Roadway Segments Interchange Influence Distance 1828

Refer to SafetyAnalyst wiki page with site subtype assignment

classifications. Some rural type highways require interchange influence

value for site subtype assignment.

Roadway Segments Segment Length Zero 1816

In Route/Section/Distance, the distance value for start and end location

of the segments are the same. This means the segments have 0 lengths

which creates an error in SafetyAnalyst.

Intersections Site Subtype assignment 20929

Almost all of the site subtype assignment problem is associated with

missing Traffic Control information. Note that there might be other

missing elements also but until Traffic Control data is provided, the other

missing elements cannot be identified atleast through SafetyAnalyst Post

Processing logs

Intersections Traffic Volume (aadtvpd) 1071

Intersections Invalid Legs 36

Accidents Cannot locate on system 2167

Site subtype Description Number of Non-used Elements Comment

101 2 Lane Rural Segment 368 Segment lengths too small (< 0.1 miles)

102 Multilane Undivided Rural Segments Not CalibratedMissing site subtype assignment (Check SafetyAnalyst wiki for details on

what data elements are missing)

103 Multilane Divided Rural Segments 52 Segment lengths too small (< 0.1 miles)

104 4 Lane Rural Freeway Not CalibratedMissing site subtype assignment (Check SafetyAnalyst wiki for details on


TABLE 3

Data Calibration

SUMMARY OF SAFETYANALYST DATA IMPORT, POST PROCESSING, AND CALIBRATION STATUS

Summary (Unavailable Data)

Summary (Available Data)

DETAILS OF UNAVAILABLE DATA IDENTIFIED DURING EACH STEP OF DATA IMPORT PROCESS

Data Import

Data Post Processing

105 6+ Lane Rural Freeway Not CalibratedMissing site subtype assignment (Check SafetyAnalyst wiki for details on


106 4 Lane Rural Freeway Interchange Area Not CalibratedMissing site subtype assignment (Check SafetyAnalyst wiki for details on


107 6+ Lane Rural Freeway Interchange Area Not CalibratedMissing site subtype assignment (Check SafetyAnalyst wiki for details on


151 2 Lane Urban Arterial 253 Segment lengths too small (< 0.1 miles)

152 Multilane Undivided Rural SegmentsMissing site subtype assignment (Check SafetyAnalyst wiki for details on


153 Multilane Divided Rural Segments 220 Segment lengths too small (< 0.1 miles)

154 One-way Urban Arterial 79 Segment lengths too small (< 0.1 miles)

203 3 Leg Rural Signalized Intersection Completed

206 4 Leg Rural Signalized Intersection Completed

253 3 Leg Urban Signalized Intersection Completed

256 4 Leg Urban Signalized Intersection Completed

NOTE

missing site subtype assingments for site subtype

number 155 - 160, 301-308, 351-358,

201,202,204,205,251,252

Missing site subtype assignment (Check SafetyAnalyst wiki for details on


Function Status Potential Issues and Comments

Site Details Working

Intersections and road segments can only be located based on intersection ID's and road segment ID's.

Missing road names/aliases make it difficult to visualize and identify the exact location of the route

segment or intersection, especially in urban area where intersections are often known by road names

rather than route numbers. Moreover, all minor road names are missing. Additionally, having

intersection data information by each leg would be beneficial although it is understood that that would

require substantial data collection efforts for all the intersections in Wisconsin

Accident Summary WorkingWorks well showing accident summary details by various control factors for each site (Intersection or

Road Segment)

Collision Diagrams Working Works well showing collision diagrams for total accidents or accidents by injury severity


Basic Network Screening (With peak searching on roadway segments and

CV test)Working

The results show smaller segments with length equal or close to 0.1 miles on top of the rankings.

Consider creating homogeneous segments to overcome the potential bias due to exceedingly smaller

segments

Basic Network Screening (With sliding window on roadway segments) Working

High Proportion of Specific Accident Type Working

Sudden Increase in Mean Accident Frequency Working Requires additional years AADT

Steady Increase in Mean Accident Frequency Working Requires additional years AADT

Corridor Screening Working Details required on corridor definitions


Basic Network Screening (With peak searching on roadway segments and

CV test)N/A

Basic Network Screening (With sliding window on roadway segments) N/A N/A to intersections

High Proportion of Specific Accident Type Working

Sudden Increase in Mean Accident Frequency Working Requires additional years AADT

Steady Increase in Mean Accident Frequency Working Requires additional years AADT

Corridor Screening N/A N/A to intersections


Selection of site for diagnostics WorkingEither arbitrary selection of a site or based on ranking from Network Screening results. Note that only

1 site can be selected at a time for further diagnostics

Selection of diagnostic parameters Working

Evaluation of SafetyAnalyst's Module Functions

This sheet provides summary of evaluation of all functions of four SafetyAnalyst modules for both Intersections and Road Segments. Details of potential shortfalls and improvements also

provided and how it would affect the analysis in SafetyAnalyst. Note that the analysis is limited to only valid sites (Intersections and Road Segments)

Basic Site Operations

Road Segments and Intersections

Module 1 - Network Screening

Road Segments

Intersections

Module 2 - Diagnosis and Countermeasure Selection

TABLE 4

Accident Pattern Identification (through Accident Summary, Collision

Diagram, Statistical Tests)Working

Accident Pattern Selection Working

Diagnostic Scenarios Working

Countermeasure Selection Working


Select Sites and Assign Proposed Countermeasures Working

Users can select and assign proposed countermeasures to sites. While assigning countermeasures to

sites, AMF, Service Life, and Cost data is required and provided for some countermeasures in

SafetyAnalyst. Additionally, these numbers can be edited by user to suit region or agency specifications.

There are some missing values in the list of countermeasures in SafetyAnalyst which will have to be

filled before the countermeasure can be used in analysis.

Cost Effectiveness Analysis Working

EPDO Based Cost Effectiveness Analysis Working

Benefit-Cost Ratio Analysis Working

Net Benefit Analysis Working


Implemented Countermeasure Tool Tested

The Implemented Countermeasure tool is a stand-alone tool which is used to create a list of projects

which will be evaluated in Module 4. The list of projects can be defined manually or imported through

a file along with appropriate information such as project location, details, implemented countermeasures

etc. Although there is no provision to provide the cost of the project yet, software developers are

working to modify the tool to include potential improvements specifically for Benfit Cost ratio analysis

which would be extremely useful for HSIP Evaluations

Not Tested

Note: This module has not been tested yet because it requires data related to implementation of

countermeasures which have to be imported into SafetyAnalyst. The module is not working at the

moment because potential software improvements are underway to make changes to the module.

Dummy data will be created for test purposes once all other issues have been resolved

Module 4 - Countermeasures Evaluation


Module 3 - Economic Appraisal and Priority Ranking


Note: The site diagnosis and selection of countermeasure process is fairly flexible and provides step by step questions and answers to identify relevant countermeasures. Moreover, users can skip

the question answer help for identifying countermeasures and identify countermeasures based on engineering judgement. However, this process can only be completed for valid road segments and

intersections. Although there is an extensive list of countermeasures provided in SafetyAnalyst, WisDOT can provide custom countermeasures in SafetyAnalyst provided that the appropriate cost

and AMF information associated with the countermeasure is available.

These methods require Accident cost values and/or Accident Relative weights based on PDO crashes.

Wisconsin Data Evaluation and

Assessment for SafetyAnalyst Data

Import, Post Processing, and

Calibration

Second Dataset


Steven Parker Ph.D.



May 2010

1

DISCLAIMER











1

SAFETYANALYST DATA IMPORT, POST PROCESSING, AND CALIBRATION

REPORT USING WISOCNSIN DATA

This document presents a summary of SafetyAnalyst data status after data import, post

processing, and calibration were completed by SafetyAnalyst using the second set of Wisconsin

data as received by TOPS lab. from WisDOT. The second dataset was received in view of the

recommendations, changes, and shortcomings reported in the first dataset in the previous report.

The new dataset included changes in data format reflecting the continued changes in

SafetyAnalyst software requiring a complete overhaul of the XML mapping schema. Once the

new XML mapping schema was generated, the new dataset was imported from scratch into

SafetyAnalyst and data post processing, calibration, and overview conducted again as done

previously to ensure and report on the correctness and quality of the data. It should be noted that

due to the continued changes in the software and inherent limitations in WisDOT data, some

issues were experienced with the data details of which are summarized in this report.

Major Issues

1. In the intersection, leg, legtraffic, legvehiclemovement, majortraffic, and minortraffic

datasets, numerous different intersections are assigned same IntersectionIDs.

Figure 1 Intersection Data Showing Multiple Intersections with the Same Intersection ID

2

Figure 2 Location of Multiple Intersections with the same Intersection IDs

2. 57 out of 21023 of roadway segments have inconsistent lengths with the difference of

their "Start offset" and "End offset".

List of Issues Fixed

1. Roadway segments of length zero are removed;

2. For two-way roads, road information (number of lanes, lane width, etc.) is now provided

for each direction separately;

3. Growth factor is now available;

4. Interchange influence (yes or no);

5. Minor road names are available;

6. Accident severity level is detailed.

List of Issues Not Fixed

1. All the “Alternate Routed Names” provided are essentially same as “Route Name”. This

attribute is supposed to provide alternate route number if it is a concurrent highway;

2. No “Major Road Name” is provided. This field is to provide the unnumbered road name,

if available;

3. City/town/jurisdiction info is still not available;

4. Terrain info is not available;

5. County name rather than county code is preferred, because it is more descriptive;

6. Minor road AADT is not provided.

SafetyAnalyst Limitations

3

1. SA does not provide options to input more than three auxiliary lanes for a roadway

segment;

2. SA does not provide options to handle more than two vehicles for each accident.

Details of the Post Process and Calibrate procedures are provided in Table 1, Table 2, and Figure

3 below with detailed analysis of the data available and unavailable as well as number of valid

and invalid sites in light of the new data received.

Element Total Number Number of Valid Elements % of Valid Elements


Ramps 0 0 N/A


Accidents 271499 247137 91.0

Element Total Number Number of Invalid Elements Comments

Roadway Segments 21023 4431 2168 missing AADT and 2741 missing subtype.

Ramps 0 0 Ramp data unavailable.

Intersections 54209 1750517465 missing major AADT, and 63 missing subtype. In

addition, all intersections are short of minor road AADT.

Segment Accidents 173412 0

Intersection Accidents 98087 243623385 intersection crashes missing designated intersections,

and 20977 crashes too far from designated intersections.

Element Warning Number Comment

Roadway Segments Missing Traffic Volume 2168 These are major road segments with missing volume data.

Intersections Missing Major Traffic Volume 17465

This value is similar to missing roadway segment number

(segment traffic) because intersections legs are part of the

roadway segments dataset, hence any missing information

in the roadway segment dataset would lead to missing

information for the intersection legs.


Table 1 - Summary of SafetyAnalyst Data Quality Evaluation

Summary

Summary of Invalid Data

Details of Invalid Data Identified in Each Step

Data Import

Data Post Processing


Roadway Segments Missing Traffic Volume 2168 Required for any type of analysis.

Roadway Segments No Site Subtype Assigned 2741SafetyAnalyst could not assign a site subtype value. All

invalidities are caused by missing Median Type.

Intersections Missing Major Traffic Volume 17465 Required for any type of analysis.

Intersections No Site Subtype Assigned 63

Accidents No sites found 3385

No segment or intersection could be found for the

accident. Possible reason: portion of sites were not

included or removed.

AccidentsOutside influence zone of nearest

intersection20977

The accident is too far (> 0.05 mile) from the designated

intersection. Possible solutions are either to increase the

default influence distance (0.05 mile) or to set the accident

to be a segment crash.

Distance from

IntersectionNumber of Intersection Accidents

<= 0.05 73725

0.1 9174

0.2 6607

0.3 2895

0.4 834

0.5 490

0.6 275

0.7 194

0.8 178

0.9 95

1 102

> 1 133

73725

91746607

2895834 490 275 194 178 95 102 133

0

10000

20000

30000

40000

50000

60000

70000

80000

<= 0.05 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 > 1

Distance (mile)

Figure 3 - Number of Intersection Accidents

Distance (mile)

Site Subtype Description Number of Sites Used Number of Sites Not Used Number of Accidents Comment

101 Rural 2-Lane Roads 8659 433 (< 0.1 mi) 56353

102 Rural Multilane Undivided Roads 109 41 (< 0.1 mi) 1305

103 Rural Multilane Divided Roads 761 56 (< 0.1 mi) 6155

104 Rural Freeway (4 Lanes) 1284 68 (< 0.1 mi) 16233

105 Rural Freeway (6+ Lanes) 98 9 (< 0.1 mi) 1830

106Rural Freeway within Interchange Area (4

Lanes)15 5 (< 0.1 mi) 160

Not calibrated. (Has only 15 usable sites;

minimum threshold is 30.)

107Rural Freeway within Interchange Area (6+

Lanes)18 6 (< 0.1 mi) 249



151 Urban 2-Lane Arterial Street 1311 298 (< 0.1 mi) 12017

152 Urban Multilane Undivided Arterial 391 118 (< 0.1 mi) 5794

153 Urban Multilane Divided Arterial 1082 232 (< 0.1 mi) 12799

154 Urban One-Way Arterial 126 121 (< 0.1 mi) 1388

155 Urban Freeway (4 Lanes) 814 59 (< 0.1 mi) 13182

156 Urban Freeway (6 Lanes) 283 30 (< 0.1 mi) 13374

157 Urban Freeway (8+ Lanes) 15 4 (< 0.1 mi) 686Not calibrated. (Has only 15 usable sites;


158Urban Freeway within Interchange Area (4

Lanes)48 14 (< 0.1 mi) 911

159Urban Freeway within Interchange Area (6

Lanes)65 15 (< 0.1 mi) 3351

160Urban Freeway within Interchange Area

(8+ Lanes)4 0 282



Rural 3-Leg Intersection with Minor-Road

Data Calibration

Table 2 - Summary of SafetyAnalyst Data Quality Evaluation

201Rural 3-Leg Intersection with Minor-Road

STOP Control19753 0 7631

202Rural 3-Leg Intersection with All-Way STOP

Control0 0 0 Not calibrated. (No site available.)

203 Rural 3-Leg Intersection with Signal Control 101 0 810

204Rural 4-Leg Intersection with Minor-Road


205Rural 4-Leg Intersection with All-Way STOP

Control0 0 0 Not calibrated. (No site available.)

206 Rural 4-Leg Intersection with Signal Control 95 0 754

251Urban 3-Leg Intersection with Minor-Road


252Urban 3-Leg Intersection with All-Way

STOP Control0 0 0 Not calibrated. (No site available.)

253Urban 3-Leg Intersection with Signal

Control729 0 8000

254Urban 4-Leg Intersection with Minor-Road


255Urban 4-Leg Intersection with All-Way

STOP Control0 0 0 Not calibrated. (No site available.)

256Urban 4-Leg Intersection with Signal

Control1321 0 15572

Description Comments

Incorrect Subtype

A large number of 4-way intersections are

divided into two 3-leg intersections in the

dataset. This has severe effect on the

accuracy of the SPFs and all the analyses

using these functions.

Unclear Segment ID

Current Route/Section/Distance location is

hard to use to identify a segment. It is

recommended more descriptions of the

sections are provided.

Municipality Info

Unavailable

Neither roadway segments nor

intersections have municipality info

available. Without these data, municipality

wide analysis is very difficult.

Other Issues

SafetyAnalyst Evaluation and System

Requirements Assessment

Module 1: Network Screening

Module 4: Evaluation of Implemented Countermeasures

Andrea Bill, Research Assistant

Shuguang Hao, Research Assistant


University of Wisconsin–Madison


July, 2011

i

DISCLAIMER

This research was funded by the Wisconsin Department of Transportation. The contents

of this report reflect the views of the authors who are responsible for the facts and accuracy of

the data presented herein. The contents do not necessarily reflect the official views of the

Wisconsin Department of Transportation at the time of publication.

This document is disseminated under the sponsorship of the Department of

Transportation in the interest of information exchange. The United States Government assumes

no liability for its contents or use thereof. This report does not constitute a standard,

specification, or regulation.




ii

TABLE OF CONTENTS

I. INTRODUCTION ...................................................................................................... 1

SafetyAnalyst .............................................................................................................................. 1

Highway Safety Improvement Program (HSIP)—Year 2006 .................................................... 2

Objectives ................................................................................................................................... 2

II. DATA IMPORT AND MANAGEMENT ..................................................................... 3

Wisconsin Data ........................................................................................................................... 3 Software Issues ..................................................................................................................................................... 4 Data Structure Issues ........................................................................................................................................... 4 Missing Data and Data Accuracy Issues ............................................................................................................. 4

III. USING SAFETYANALYST ANALYTICAL TOOL ................................................... 6

IV. CREATING 5-PERCENT REPORT USING NETWORK SCREENING ....................... 7

Comments ................................................................................................................................... 8

V. EVALUATION OF HSIP PROJECTS USING SAFETYANALYST .............................. 9

Project 1: FOS 10220674 (I-94 & CTH-B, Menominie, Dunn County) .................................. 13

Project 2: FOS 11504371 (US-41 & CTH SS, Pensaukee, Oconto County) ............................ 15

Project 3: FOS 15300191 (WI-35 & US-10, Prescott, Pierce County) .................................... 17

Project 4: FOS 22001570 (US-18 & CTH C, Genesee, Waukesha County) ............................ 19

Project 5: FOS 22401570 (US-45 & CTH H, Franklin, Milwaukee County) .......................... 21

Project 6: FOS 40500971 (WI-55 & CTH KK, Harrison, Calumet County) ........................... 23

Project 7: FOS 44790371 (US-10/WI-114 & CTH LP, Menasha, Calumet County) .............. 25

Project 8: FOS 45401572 (WI-28 & WI-32, Sheboygan Falls, Sheboygan County) ............... 27

Project 9: FOS 46851471 (WI-441 & CTH OO, Little Chute, Outgamie County) .................. 29

Project 10: FOS 50600072 (WI-23, from WI-33 to Pickerel Slough, Lake Delton, Sauk

County) ......................................................................................................................... 31

Project 11: FOS 52520071 (US-53(NB) & Monitor St., La Crosse, La Crosse County) ......... 33

Project 12: FOS 69960674 (WI-16, from MacFarlane Ln. to Dewitt St., Portage, Columbia

County) ......................................................................................................................... 35

Project 13: FOS 69991072 (Bus. 51 & CTH XX, Rothschild, Marathon County) .................. 37

Project 14: FOS 70300370 (US-10 & Grand Ave., Neillsville, Clark County) ....................... 39

Project 15: FOS 72200191 (WI-25 & Main St., Menominie, Dunn County)........................... 41

Project 16: FOS 86100270 (WI-312 & Old Wells, Eau Claire, Eau Claire County) ............... 43

Project 17: FOS 86810571 (US-2 & Banks Ave., Superior, Douglas County) ........................ 45

Project 18: FOS 92000371 (WI-29 & CTH VV, Howard, Brown County) ............................. 47

VI. CONCLUSIONS AND RECOMMENDATIONS ........................................................49

APPENDIX 1: RESULTS OF NETWORK SCREENING .................................................51

Table A.1 — 5% Screening of SW Region Intersections ......................................................... 51

Table A.2 — 5% Screening of SW Region Segments .............................................................. 52

Table A.3 — 5% Screening of SE Region Intersections .......................................................... 62

iii

Table A.4 — 5% Screening of SE Region Segments ............................................................... 68

Table A.5 — 5% Screening of NE Region Intersections ......................................................... 73

Table A.6 — 5% Screening of NE Region Segments .............................................................. 74

Table A.7 — 5% Screening of NC Region Intersections ......................................................... 80

Table A.8 — 5% Screening of NC Region Segments .............................................................. 80

Table A.9 — 5% Screening of NW Region Intersections ........................................................ 88

Table A.10 — 5% Screening of NW Region Segments ........................................................... 88

1

I. INTRODUCTION

SafetyAnalyst

SafetyAnalyst is a software package composed of a set of state-of-the-art analytical tools

for use in the decision-making process to identify and manage a system-wide program of

site-specific improvements to enhance highway safety by cost-effective means and the

only one being undertaken at the national level. The Transportation Research Board

(TRB) is leading the initiative to develop the Highway Safety Manual (HSM) that could

be used to make estimates of traffic safety performance in the same sense as traffic

operational performance estimates using the Highway Capacity Manual (HCM). HSM is

intended to provide a quantitative basis for estimating the safety performance of an

existing highway or street and for estimating the effects of proposed improvement

projects. As a result, parts IV and V of HSM will include the basic concepts that have

been developed for SA. Highway agencies will be able to use SA to investigate the

potential benefits of specific safety improvements and conduct a thorough economic

analysis.

The software focuses on identifying the need for improvements at specific highway sites,

identifying the most appropriate improvements for those sites, and making cost-effective

choices to set priorities among the potential improvements. It can also make reliable

estimates of the safety effectiveness of countermeasures that are implemented by

highway agencies. SafetyAnalyst addresses site-specific safety improvements that

involve physical modifications to the highway system. It integrates all parts of the safety

management process and streamlines all steps of the process that have been performed

manually in the past. The general safety management process can be described in six

main steps:

Step 1: Identification of sites with potential for safety improvement

Step 2: Diagnosis of the nature of safety problems at specific sites

Step 3: Selection of countermeasures at specific sites

Step 4: Economic appraisal for sites and countermeasures under consideration

Step 5: Priority rankings of improvement projects

Step 6: Safety effectiveness evaluation of implemented countermeasures

The analytical tool in SafetyAnalyst is comprised of four modules which, when packaged

together, incorporate the six main steps for highway safety management:

Module 1: Network screening

Module 2: Diagnosis and countermeasure selection

Module 3: Economic appraisal and priority ranking

Module 4: Countermeasure evaluation

This evaluation is based on SafetyAnalyst ver. 4.0.0-Jan. 21, 2010.

2

Highway Safety Improvement Program (HSIP)—Year 2006

The safety provision of the new transportation act “Safe, Accountable, Flexible, Efficient

Transportation Equity Act: A Legacy for Users” (SAFETEA-LU) highlights the

importance of transportation safety and dramatically increases funding for safety

improvements. One significant feature of the act is that the Hazard Elimination Safety

(HES) program is replaced by the Highway Safety Improvement Program (HSIP) and

promoted to the equal level as the Surface Transportation Program (STP). Given the

emphasis on this program, it is important that FHWA be able to demonstrate that the

program is being effectively implemented, and the projects being constructed are

achieving anticipated results. As a result, an annual report on the HSIP implementation

and effectiveness is required by 23 U.S.C. §148(g).

In 2009, Wisconsin Department of Transportation (WisDOT) of Transportation

Investment Management (DTIM), with the assistance of the University of Wisconsin

Traffic Operations and Safety (TOPS) Laboratory, conducted a WisDOT HES/HSIP

program evaluation. A total of 18 HSIP projects completed in FY 2006 were evaluated.

According to the project locations and scheduled start and completion dates, the TOPS

Laboratory developed a process to extract appropriate crashes (by location, type and

year) from the WisDOT crash database. Five years of “before” and two to three years of

“after” crash data were retrieved for each project to evaluate HES/HSIP projects using

Before-After and Empirical Bayes evaluation methods. Fatal and injury crashes were the

focus but the analysis was extended to target crashes based on the nature of the projects.

Moreover, a Benefit-Cost analysis was also performed to provide an economic

perspective to the evaluation based on both the Before-After and Empirical Bayes

analyses.

Objectives

The primary purpose of HSIP is to establish policy for the development and

implementation of a comprehensive highway safety program in each state including

components for planning, implementation, and evaluation of safety programs and

projects. These components consist of processes developed by states and approved by

FHWA. To qualify for funding for these programs, States must have an approved SHSP

that provides directions and guidelines for allocating their funds. SafetyAnalyst is

designed to meet these requirements and needs.

The goal of this assessment is to test the use of SafetyAnalyst in Wisconsin highway

safety agencies using Wisconsin data, evaluate SafetyAnalyst analytical functions, and

validate the results. Recommendation from the evaluation will be considered to enhance

current practical applications.

In this report, the evaluation focuses on the Benefit-Cost analysis using Empirical Bayes

method. The 18 HSIP projects of FY 2006 evaluated in 2009 are re-evaluated using

SafetyAnalyst. In addition, the network screening tool and overall software usability are

also assessed.

3

II. DATA IMPORT AND MANAGEMENT

The highway inventory, traffic volume, crash history, and project countermeasures

information need to be imported into a database accessible to SafetyAnalyst before any

analysis. The raw data can be pre-stored in either a sophisticated database or simply

several text files. These datasets are imported into the SafetyAnalyst managed database.

Then, the data are post-processed and calibrated using the SafetyAnalyst Data

Management Tool.

During post processing, SafetyAnalyst performs these tasks:

• connects segments to each other and to intersections;

• locates accidents on the inventory (segments, intersections, and ramps);

• assigns site subtypes to the inventory;

• optionally combines segments into homogeneous segments;

• validates traffic volume data; and

• performs other data validation

During post processing, if an inventory element does not have any valid traffic data, it is

rejected (removed from the data set). If traffic data are available but incomplete (e.g.,

missing years) the post processing will interpolate and/or apply a growth factor to

estimate traffic counts. Also during this phase, accidents that cannot be located on one of

the valid inventory elements will be rejected.

An imported and post processed data set is still not ready for use until it has been

calibrated. During calibration, accident (crash) distributions are computed for the

inventory based on site subtype and accident severity. Also during this phase, data set

calibration factors are computed for the Safety Performance Functions (SPF) employed

by the SafetyAnalyst Analytical Tool.

After the inventory, traffic, and accident datasets are ready, the HSIP projects are

manually entered using either Data Management Tool or the specific Implemented CM

Tool. Each project can have one or multiple sites (intersection, segment, or ramp) and

each site can have a single or multiple countermeasures.

Wisconsin Data

SafetyAnalyst provides several options to import the data. After extensive discussions

and research, it was decided to use the database to database import using the

SafetyAnalyst XML mapping capabilities.

WisDOT provided the inventory, traffic, and crash datasets in CSV files. These data are

imported into an Oracle database. Then, they are imported into another schema using the

SafetyAnalyst database-to-database map. After that, the post-processing and calibration

procedures are standard.

4

There were two major types of issues encountered during the data import process, namely

software issues and data issues. The data issues can be further subdivided into two types

i.e., data structure issues and missing data or data accuracy issues.

Software Issues

SafetyAnalyst has been out of testing stage and released to production. Various critical

issues found in previous evaluations have been fixed. Although the software is now

transferred to AASHTO, the developers are still working on improvement. Pending

critical bugs include:

• Some crashes that occurred at the same location are mapped to different sites.

We have reported these issues to the developers.

Data Structure Issues

In the previous evaluations, several changed were made to the structure of the CSV files

generated by WisDOT, because of the changes in the data requirement of SafetyAnalyst.

This problem was partially solved by creating database views to conform to the

requirement of SafetyAnalyst. However, now that the data requirement has been finalized,

it is recommended that WisDOT along with TOPS Lab discuss the issues related to data

structure so that the future effort required by WisDOT in generating the input CSV files

is minimized. The aim is to use the SafetyAnalyst internal mapping capabilities to

directly import data from WisDOT sources. For example, currently enumeration values

for certain data elements are changed by WisDOT to conform to SafetyAnalyst input

values. Ideally, we would like to make those changes in the SafetyAnalyst import map

rather than during the generation of the input CSV files at WisDOT.

Missing Data and Data Accuracy Issues

Currently the major issue with the data provided by WisDOT is that some critical data

elements are missing or incorrect. Some missing data elements created issues during the

data import, post processing, and calibration steps. Other missing data elements affected

the performance of the Analytical Tool and functions of the four SafetyAnalyst modules

by invalidating sites with missing data. If a site is invalidated due to missing data

elements in SafetyAnalyst, analysis cannot be performed on that site, although it remains

part of the dataset.

• Traffic volume data are essential for almost all safety analyses. However, a large

portion of the roadway segments are not provided with this information and none

of the intersections has minor road traffic volume available. In addition, only year

2007 AADT is provided and at least two years data are preferred to calculate the

growth factors.

• Incomplete or incorrect information of site subtypes can also invalidate a site.

5

• Incorrect AADT or subtype of a single site can affect the calibrated Safety

Performance Functions and thus affect the results of the analyses performed on

the entire network.

• Lack of geographic descriptions of sites makes it difficult to locate a specific site.

Currently, the intersections are provided with minor road names, but the roadway

segments are identified by distances which do not have obvious meaning.

The warnings and errors that occur in the data import process are summarized as follows:

• 39266 warnings are reported in the import step, all are which are related to

missing AADT.

• 74226 warnings are reported in the post-processing.

o 7221 out of 21023 segments are marked as invalid, 2168 of them are short

of AADT data and 5734 cannot be assigned with subtypes;

o 17505 out of 54209 intersections are marked as invalid, 17465 of them are

short of AADT data and 63 cannot be assigned with subtypes;

o 24363 out of 271499 crashes are marked as invalid because they cannot be

located.

The calibration step is summarized in Table 1:

Table 1—Summary of calibration

ID Subtype Sites Used Sites not Used* Crashes Used

101 Seg/Rur; 2-lane 8659 433 56353

102 Seg/Rur; Multilane undivided 0 0 0

103 Seg/Rur; Multilane divided 0 0 0

104 Seg/Rur; Fwy (4 ln) 1284 68 16233

105 Seg/Rur; Fwy (6+ ln) 98 9 1830

106 Seg/Rur; Fwy in intchng area (4 ln) 15 5 160

107 Seg/Rur; Fwy in intchng area (6+ ln) 18 6 249

151 Seg/Urb; 2-lane arterial 1311 298 12017

152 Seg/Urb; Multilane undivided 0 0 0

153 Seg/Urb; Multilane divided 0 0 0

154 Seg/Urb; One-way arterial 126 121 1388

155 Seg/Urb; Fwy (4 ln) 814 59 13182

156 Seg/Urb; Fwy (6 ln) 283 30 13374

157 Seg/Urb; Fwy (8+ ln) 15 4 686

158 Seg/Urb; Fwy in intchng area (4 ln) 48 14 911

159 Seg/Urb; Fwy in intchng area (6 ln) 65 15 3351

160 Seg/Urb; Fwy in intchng area (8+ ln) 4 0 282

201 Int/Rur; 3-leg minor-rd STOP 19753 0 7631

202 Int/Rur; 3-leg all-way STOP 0 0 0

203 Int/Rur; 3-leg signalized 101 0 810

6

204 Int/Rur; 4-leg minor-rd STOP 2690 0 4469

205 Int/Rur; 4-leg all-way STOP 0 0 0

206 Int/Rur; 4-leg signalized 95 0 754

251 Int/Urb; 3-leg minor-rd STOP 9601 0 15521

252 Int/Urb; 3-leg all-way STOP 0 0 0

253 Int/Urb; 3-leg signalized 729 0 8000

254 Int/Urb; 4-leg minor-rd STOP 2414 0 10106

255 Int/Urb; 4-leg all-way STOP 0 0 0

256 Int/Urb; 4-leg signalized 1321 0 15572

*Note: Segments shorter than 0.1 mile are not used for calibration.

III. USING SAFETYANALYST ANALYTICAL TOOL

Before any analysis, a site list is created. The list contains all the sites (intersections,

roadway segments, and ramps) of interest, as shown in Figure 1. In this figure, the analyst

can verify information of each site, such as traffic volume, accidents, and

countermeasures implemented at the site.

Figure 1—SafetyAnalyst Analytical Tool

After the site list is created, the analyst can perform various analyses on it using the four

modules. In the next two sections, Module 1 Network Screening and Module 4

Countermeasure Evaluation are evaluated.

7

IV. CREATING 5-PERCENT REPORT USING NETWORK SCREENING

Identifying the intersections that exhibit an abnormally high number of crashes,

specifically severe crash consequences and their causes, becomes one of the most

important tasks for researchers and engineers. One strong initiative for accelerating the

process is the FHWA “5 Percent Report” that requires states to prepare an annual report

describing “not less than 5 percent of their highway locations exhibiting the most severe

safety needs”. For this reason, SafetyAnalyst provides an option to the analyst to select

roadway network to be considered in generating 5-percent reports.

SafetyAnalyst provides six network screening approaches for identifying potential sites

for safety improvement. These are:

• Basic Network Screening with Peak Searching and CV Test;

• Basic Network Screening with Sliding Window;

• High Proportion of Specific Accident Type;

• Sudden Increase in Mean Accident Frequency;

• Steady Increase in Mean Accident Frequency; and

• Corridor Screening.

The Sliding Window approach was traditionally popular but SafetyAnalyst recommends

the Peak Searching and CV Test approach because of its statistical reliability. The next

three approaches are not applicable for 5% screening.

In this evaluation, we performed 5% network screening on the intersections and segments,

respectively, for each of the five regions of Wisconsin. Before the analysis, a site list is

created for all the intersections/segments of each region. After the site list is created,

Module 1 Network Screening is used to generate the 5% report.

The following parameters are used:

• Percentage report: 5%

• Basic Network Screening with Peak Searching and CV Test

• Accident Severity Levels: All

• Safety Performance Measure: Expected accident frequency

• Analysis Period: All five years

• Area Weight: Rural to Urban = 1.0

• Accident Frequency Limiting Values

o Intersections: 5 crashes/year

o Segments: 5 crashes/mile/year

• Coefficient of Variation

o Intersections: 0.5

o Segments: 0.5

8

Only sites which have higher crash rates than the limiting value are evaluated. The results

are summarized in Table 2. The detailed lists of the sites flagged are included in the

Appendix .

Table 2—Summary of 5% Report

Region

Intersections Segments

Total Sites

Evaluated

Sites

Flagged Percentage Total

Sites

Evaluated

Sites

Flagged

Length

Evaluated

Length

Flagged Percentage

SW 10355 6953 36 0.52% 5739 4035 238 3208.8 160 5.0%

SE 9826 7944 170 2.14% 3708 1812 93 1086.77 54.15 5.0%

NE 6337 4594 35 0.76% 3432 2062 128 1503.52 74.46 5.0%

NC 19999 12343 7 0.06% 3727 2561 177 2215.86 110.44 5.0%

NW 7692 4870 8 0.16% 4417 3332 195 2850.96 142.27 5.0%

Comments

1. For each region, roughly 5% of all segments by length are flagged. However, far

fewer intersections are selected. This seems to be a pending issue with

SafetyAnalyst;

2. In the raw data provided by WisDOT, an intersection can be located by its major

and minor route number and/or name. However, a segment can only be identified

by route number, section, and distance. The segment section and distance are not

obviously meaningful and make it difficult to locate a segment;

3. The results show smaller segments with length equal or close to 0.1 miles on top

of the rankings. Creating homogeneous segments can be considered to overcome

the potential bias due to exceedingly smaller segments. There is option available

to generate homogeneous segments from input dataset because generally, smaller

length segments tend to skew the results because of larger crash rates. This is a

technical issue which needs further discussion with WisDOT and Safety

Engineers before a decision is reached.

9

V. EVALUATION OF HSIP PROJECTS USING SAFETYANALYST

A total of 18 HSIP projects, with the cost ranging from $24,000 to $794,000, are

evaluated in detail in the following sections. The projects cover a wide spectrum of

highway safety improvements and enhancements, such as lane reconfiguration, traffic

signal enhancements, pavement friction improvement, installation of weather sensing

equipment, and so on. Each project evaluation started with a project description,

followed by the countermeasures applied, and a comparison of the evaluation in 2009 and

that using SafetyAnalyst.

Before this evaluation, a site list is created for each project. The list contains all the

intersections, roadway segments, and ramps involved in the project. After the site list is

created, Module 4 Countermeasure Evaluation is used for analysis of either a single

countermeasure or a project, using Empirical Bayes based method. Benefit-Cost analysis

can be optionally performed.

In the analysis, the user has options to change several parameters and settings. The

benefit-cost analysis can be performed using either all crashes or a portion of them based

on crash severity, collision type, vehicle movement, etc. The user can also select span of

the before and after periods. In addition, the default costs of each type of crash can also

be changed.

In this evaluation, the following settings are used:

• Accident costs:

o Fatal: $5,800,000

o Severe injury: $402,000

o Non-incapacitating injury: $ 80,000

o Possible injury: $ 42,000

o Property damage only: $4,000

• Minimum attraction rate of return: 4%

• Service life of project: 10 years

• Default minor road traffic volume if not available: 1000 vehicles per day

Table 3 presents an overall summary of the 18 projects. Table 4 presents summary results

of the Benefit-Cost analysis from the evaluation in 2009 and the results from

SafetyAnalyst.

11

Table 3— Summary of HSIP Projects Completed in FY 2006

FOS ID Schedule Date Region County Route Concept Site Type Location Total Cost

10220674 6/13/2006 NW Dunn 094 Traffic Signal Installation Ramp CTH B Interchange Ramps $206,000

11504371 6/13/2006 NE Oconto 041 Intersection Reconstruction Intersection CTH SS & Brookside Cemetery Rd. $145,000

15300191 2/25/2006 NW Pierce 010 Traffic Signal Installation Intersection Cherry St. & USH 10 Intersection $24,000

22001570 4/25/2006 SE Waukesha 018 Traffic Signal Installation Intersection USH 18 & CTH C (East Junction) $340,346

22401570 4/11/2006 SE Milwaukee 045 Traffic Signal Installation Intersection Intersection with CTH H (Ryan Rd.) $140,000

40500971 5/9/2006 NE Calumet 055 Roundabout Installation Intersection STH 55 & CTH KK $794,000

44790371 6/13/2006 NE Calumet 010 Intersection Reconstruction/Traffic Signal Installation Intersection USH 10/STH 114 & CTH LP $260,000

45401572 4/11/2006 NE Sheboygan 032 Roundabout Installation Intersection STH 32 & STH 28 $250,000

46851471 12/13/2005 NE Outagamie 441 Intersection Reconstruction Ramp CTH OO SE Ramp $79,000

50600072 3/14/2006 SW Sauk 023 Segment Reconstruction Segment STH 33 - Lake Delton Rd. $619,000

52520071 5/9/2006 SW LaCrosse 053 Traffic Signal Installation Intersection Rose St. & Monitor $125,000

69960674 7/12/2005 SW Columbia 051 Traffic Signal Update/Coordination Segment Macfarlane Rd - Dewitt St. $110,000

69991072 5/9/2006 NC Marathon 051 Intersection Reconstruction Intersection Bus 51 & Imperial Ave. $217,000

70300370 3/14/2006 NW Clark 010 Traffic Signal Installation Intersection Grand Avenue Intersection $456,000

72200191 1/25/2006 NW Dunn 025 Traffic Signal Location Modification Intersection Main Stree Intersection $11,000

86100270 6/13/2006 NW Eau Claire 312 Intersection Reconstruction/Traffic Signal Installation Intersection Old Wells Rd. Intersection $199,000

86810571 2/14/2006 NW Douglas 002 Intersection Reconstruction Intersection Belknap St. (USH 2) $334,000

92000371 6/13/2006 NE Brown 029 Intersection Reconstruction Intersection STH 29/32 & CTH VV $347,000

12

Table 4—Summary of Benefit-Cost Analysis Results

S. No. FOS ID Benefit-Cost Ratios

HSIP Evaluation in 2009 SA with All Crashes SA with Target Crashes

1 1E+07 1.38 NA NA

2 1.2E+07 31.64 1.53 1.12

3 1.5E+07 5.34 -133.64 -90.35

4 2.2E+07 1.39 0.24 1.21

5 2.2E+07 7.72 9.65 7.98

6 4.1E+07 1.01 NA NA

7 4.5E+07 5.14 3.93 3.36

8 4.5E+07 1.66 NA NA

9 4.7E+07 1.22 NA NA

10 5.1E+07 0.76 -20.38 0.86

11 5.3E+07 1.04 -0.68 -1.86

12 7E+07 1.58 -16.33 -2.49

13 7E+07 -1.19 1.27 1.03

14 7E+07 0.33 3.09 3.15

15 7.2E+07 13.09 29.88 0.00

16 8.6E+07 1.71 2.64 1.45

17 8.7E+07 1.44 NA NA

18 9.2E+07 2.00 -0.92 -2.34

13

Project 1: FOS 10220674 (I-94 & CTH-B, Menominie, Dunn County)

FOS Region County Municipality Site Type Major Road Minor Road Cost

10220674 NW Dunn Menominie Ramp I-94 CTH B $206,000

Safety Issues and General Information

1. The intersections in this project are the off-ramp terminals of I-94 at CTH B.

2. A growing industrial park off of this interchange caused a significant increase in

volume, especially in trucks, which accounted for about 17.5% of all traffic.

3. Target crashes were set to angle and rear-end based on the signal installation.

Crashes Summary

Before Period Before Crashes After Period After Crashes B/C Ratio

Evaluation 2009 6/13/2001-

6/13/2006 18

12/13/2006-

12/31/2008 8 1.38

SafetyAnalyst 2003-2005 NA 2007 NA NA

14

Countermeasures

1. Signals were installed to reduce angle related crashes and provide sufficient gaps

for turning trucks.

2. The right turn bays were extended at both ramp terminals to provide more storage

and increase LOS.

Results Summary

1. Examining detailed descriptions of the crashes used in the evaluation in 2009

shows that a few of them actually occurred on I-94 rather than the ramps.

2. Although SafetyAnalyst is capable of evaluating ramp projects, data are not

available; i.e., neither traffic volume nor crashes are provided.

15

Project 2: FOS 11504371 (US-41 & CTH SS, Pensaukee, Oconto County)


11504371 NE Oconto Pensaukee Intersection US-41

CTH SS/

Brookside

Cemetery Rd.

$145,000


1. The intersection of USH 41 with STH SS (Brookside Cemetery Rd.) is in Oconto

County.

2. CTH SS intersected USH 41 at a 60 degree angle. Based on the high number of

right angle crashes, it was thought that motorists had a hard time looking back

over their shoulder to see oncoming traffic before they tried to cross USH 41.

3. Target crashes for the project are angle crashes.

Crashes Summary

Before Period Before Crashes After Period After Crashes B/C Ratio

Evaluation 2009 6/13/2001-

6/13/2006 8

12/13/2006-

12/31/2008 1 31.64

SafetyAnalyst 2003-2005 4 (3) 2007 0 (0) 1.53 (1.12)

Note: Numbers in parenthesis are based on target crashes

16

Countermeasures

1. Both Brookside Cemetery Rd and CTH SS were realigned to intersect USH 41 at

70 and 75 degree angles respectively, greatly increasing the sight distance for

drivers on the minor streets.

Results Summary

1. The extremely high B-C ratio in the evaluation in 2009 is caused by the reduction

in fatalities from 1 to 0.

2. Traffic volume of the minor road (CTH SS) is not available and default value of

1000 vehicles per day is used in the evaluation using SafetyAnalyst.

3. In the evaluation in 2009 the major and minor traffic volumes are 5150 and 210

respectively, for year 2001, with a growth factor 2%. In the evaluation using

SafetyAnalyst they are 5020 and 1000 respectively, for year 2007, with the

growth factor being 4%.

4. This intersection is a rural four-leg intersection, but in the data used in

SafetyAnalyst it is treated as two three-leg intersections.

5. There are very few crashes and this means the result might not be reliable.

17

Project 3: FOS 15300191 (WI-35 & US-10, Prescott, Pierce County)

FOS Region County Municipality Site Type Major Road Minor

Road Cost

15300191 NW Pierce Prescott Intersection WI-35 US-10/

Cherry Rd. $24,000


1. The bridge at the intersection of US-10 and WI-35 serves as a major gateway

between Pierce County and the Twin Cities Metro Area. US-10 traffic coming

into WI was the only movement to not stop and makes a 90 degree turn in the

intersection. The large volume of traffic making this turn, combined with the

unusual three way stop, caused a high number of crashes.

2. Target crashes were angle and rear end.

Crashes Summary

Before Period Before Crashes After Period

After

Crashes B/C Ratio

Evaluation 2009 2/25/2001-

2/25/2006 17

8/25/2006-

12/31/2008 17 5.34

SafetyAnalyst 2003-2005 3 (3) 2007 6 (4) -133.64 (-90.35)


18

Countermeasures

1. Traffic signals were installed to alleviate this problem.

Results Summary

1. The evaluation in 2009 included large number of crashes on adjacent segments

and another intersection not related to the project.

2. Traffic volume of the minor road (Cherry Rd.) is not available and default value

of 1000 vehicles per day is used in the evaluation using SafetyAnalyst.





4. This intersection is a rural four-leg intersection, but it is treated as a three-leg

intersection in the data used in SafetyAnalyst.

5. Some crashes are not assigned or incorrectly assigned to the sites in SafetyAnalyst

which might be due to a software issue.

6. The extreme B-C ratio resulted from SafetyAnalyst is caused by reason stated

above.

19

Project 4: FOS 22001570 (US-18 & CTH C, Genesee, Waukesha County)


22001570 SE Waukesha Genesee Intersection US-18/

Summit Ave.

CTH C/

Kettle

Moraine Dr.

$340,346


1. SB traffic on CTH C turning left onto USH 18 had a history of colliding with US-

18 EB traffic. This was thought to be caused by the slight skew of the intersection

and possibly sight distance issues.


Crashes Summary


After

Crashes B/C Ratio

Evaluation 2009 4/25/2001-

4/25/2006 31

10/25/2006-

12/31/2008 12 1.39

SafetyAnalyst 2003-2005 8 (7) 2007 6 (3) 0.24 (1.21)


20

Countermeasures

1. To fix the problem, traffic signals were installed in 2006.

Results Summary

1. The evaluation in 2009 incorrectly included crashes that occurred at the west

intersection of US-18 and CTH C besides the east one.

2. Traffic volume of the minor road (Kettle Moraine Dr.) is not available and default

value of 1000 vehicles per day is used in the evaluation using SafetyAnalyst.





4. This intersection is a rural four-leg intersection, but it is treated as a three-leg

intersection in the data used in SafetyAnalyst. However, this is acceptable

because the south leg is not critical for the project.

5. The B-C ratio based on the reduction of target crashes shows that this project is

economically worthwhile.

21

Project 5: FOS 22401570 (US-45 & CTH H, Franklin, Milwaukee County)


22401570 SE Milwaukee Franklin Intersection US-45/WI-36/

W Loomis Rd.

CTH H/

Ryan Rd. $140,000


1. The intersection was originally constructed with a skew of 49 degrees. This

factor, combined with a heavy WB to SB turning movement, resulted in increased

numbers of angle crashes, specifically to a crash rate of 1.03 in 2004.


Crashes Summary


After

Crashes B/C Ratio

Evaluation 2009 4/1/2001-

4/11/2006 19

10/11/2006-

12/31/2008 3 7.72

SafetyAnalyst 2003-2005 17 (16) 2007 1 (1) 9.65 (7.98)


22

Countermeasures

1. Traffic signals were installed in 2006.

Results Summary

1. Traffic volume of the minor road (Ryan Rd.) is not available and default value of




SafetyAnalyst they are 15030 (NB), 16800 (SB), and 1000 respectively, for year

2007, with the growth factor being 4%.

3. This intersection is a four-leg intersection, but it is treated as two four-leg

intersections; one of them is for the southbound approach and the other one being

northbound approach.

4. The two analyses are perfectly consistent. Inspection of detailed descriptions of

the crashes used in both of them shows that the same crashes are used.


economically worthwhile. In fact, almost all crashes are target crashes.

23

Project 6: FOS 40500971 (WI-55 & CTH KK, Harrison, Calumet County)


40500971 NE Calumet Harrison Intersection WI-55/

Crooke Ave. CTH KK $794,000


1. Not only was the intersection located on a curve, but motorists needed to navigate

across an 8% super elevation in order to cross the intersection causing a high rate

of angle crashes. A roundabout was installed in order to decrease this number.

2. The target crashes were angle, no collision, and sideswipe opposite direction.

Crashes Summary


After

Crashes B/C Ratio


5/9/2006 28

11/9/2006-

12/31/2008 2 1.01

SafetyAnalyst 2003-2005 0 (0) 2007 2 (0) NA


24

Countermeasures

1. A roundabout was installed in order to decrease the number of crashes observed.

Results Summary

1. In the dataset provided for SafetyAnalyst, almost no crashes could be mapped to

the intersection of interest.


respectively, for year 2001, with a growth factor 2%.

3. Neither the major road nor the minor road is provided with traffic volumes for

analysis using SafetyAnalyst.

4. B-C analysis cannot be performed due to reasons stated above.

25

Project 7: FOS 44790371 (US-10/WI-114 & CTH LP, Menasha, Calumet County)


44790371 NE Calumet Menasha Intersection US-10/WI-114 CTH LP/

Lake Park Rd. $260,000


1. Traffic was rapidly increasing in the area and the old two-way stop intersection

was unable to safely handle the added volume. Drivers became impatient and

made poor decisions, sometimes leading to crashes.

2. The target crashes were angle and rear end.

Crashes Summary


After

Crashes B/C Ratio

Evaluation 2009 6/13/2001-

6/13/2006 16

12/13/2006-

12/31/2008 1 5.15

SafetyAnalyst 2003-2005 16 (12) 2007 0 (0) 3.93 (3.36)


26

Countermeasures

1. Slotted left turn lanes were added to increase sight distance.

2. Traffic signals were installed to help increase the capacity of the intersection.

Results Summary

1. Traffic volume of the minor road (CTH H) is not available and default value of




SafetyAnalyst they are 12900 (EB), 6500 (WB), and 1000 respectively, for year


3. This intersection is a four-leg intersection, but it is treated as two three-leg

intersections.

4. The two analyses are roughly consistent. Inspection of detailed descriptions of the

crashes used in evaluations shows that the same crashes are used.


economically worthwhile. In fact, almost all crashes were target crashes.

27

Project 8: FOS 45401572 (WI-28 & WI-32, Sheboygan Falls, Sheboygan County)


45401572 NE Sheboygan Sheboygan

Falls Intersection WI-28

WI-32/

Gadding Ave. $250,000


1. Volumes on both WI-28 and WI-32 were very close. Since the intersection was

two-way stop controlled, drivers on WI-32 became very impatient with the large

queues forming due to the inability to find a suitable turning gap onto WI-28.

2. The target crashes were angle crashes only.

Crashes Summary


After

Crashes B/C Ratio

Evaluation 2009 4/11/2001-

4/11/2006 10

10/11/2006-

12/31/2008 7 1.66



28

Countermeasures

1. The intersection was converted to a roundabout in an attempt to solve the delay

and safety problems.

Results Summary

1. In the dataset provided for SafetyAnalyst, most crashes could not be mapped to

the intersection of interest.


respectively, for year 2001, with a growth factor 2%.

3. Neither the major road nor the minor road is provided with traffic volumes for

analysis using SafetyAnalyst.

4. B-C analysis cannot be performed due to lack of major road traffic volume.

29

Project 9: FOS 46851471 (WI-441 & CTH OO, Little Chute, Outagamie County)


46851471 NE Outagamie Little Chute Ramp WI-441 CTH OO/

E Northland Ave. $79,000


1. There was an increasingly significant volume of traffic using WI-441 NB off

ramp to CTH OO, which was only equipped with one LT only lane and one

LT/T/RT combination lane. It was not uncommon for vehicles to backup onto the

highway, which posed a safety risk that the speed limit on WI-441 was 65 mph.

2. The target crashes were rear end crashes only.

Crashes Summary


After

Crashes B/C Ratio

Evaluation 2009 12/13/2001-

12/13/2005 50

6/13/2006-

12/31/2008 18 1.22



30

Countermeasures

1. Rear end crashes were very common due to the queuing, so a RT lane was

installed to decrease the queue length and also to let the large number of right

turning vehicles to turn on red.

Results Summary

1. Examining detailed descriptions of the crashes used in the evaluation in 2009

shows that a large portion of them actually occurred on I-94 and far from the

ramps.

2. Although SafetyAnalyst is capable of evaluating ramp projects, data are not

available; i.e., neither traffic volumes of the ramp or minor road nor crashes are

provided. In fact, all crashes included in the dataset occurred on the main

highway.

31

Project 10: FOS 50600072 (WI-23, from WI-33 to Pickerel Slough, Lake Delton,

Sauk County)

FOS Region County Municipality Site Type Road From To Cost

50600072 SW Sauk Lake Delton Segment WI-23 WI-33 Pickerel Slough $619,000


1. The STH 23 road segment is located in Sauk County, Southwest of Lake Delton.

2. Four curves located on STH 23 at Herwig Rd, Shady Ln, 0.5 miles South of

Pickerel Slough Rd, and .3 miles North of Reedsburg Rd had a history of a lot of

non-collision crashes. The curves were all sub standard, with narrow shoulders

and variable super elevation, with a posted speed of 40 mph.

3. The target crashes were angle and no collision crashes.

Crashes Summary


After

Crashes B/C Ratio

Evaluation 2009 3/14/2001-

3/14/2005 53

9/14/2006-

12/31/2008 12 0.76

SafetyAnalyst 2003-2005 19 (6) 2007 15 (0) -20.38 (0.86)


32

Countermeasures

1. The road segment was reconstructed with smoother curves and wider shoulders

with wider clear zones to alleviate the problem.

Results Summary

1. The evaluation in 2009 did not distinguish segment crashes and intersection

crashes. The traffic volume of the segment is 2050 for year 2001, with a growth

factor 2%.

2. This segment intersects eleven minor roads. None of the minor roads is provided

with traffic volumes; therefore, default value of 1000 vehicles per day is used in

the analysis using SafetyAnalyst.

3. In the evaluation using SafetyAnalyst the segment traffic volume is 2840 for year


4. The evaluation in 2009 included a large number of crashes that did not occur on

the segment of interest.

5. Only a small portion of the crashes are target crashes. Based on these crashes, the

B-C ratio is 0.86 which is less than one, so the project is not economically

worthwhile.

33

Project 11: FOS 52520071 (US-53(NB) & Monitor St., La Crosse, La Crosse

County)


52520071 SW La Crosse La Crosse Intersection US-53/Rose St.

(North Bound) Monitor St. $125,000


1. Due to the high volume at the intersection, numerous right angle crashes occurred.

2. The target crashes were angle, head on, no collision, rear end, and sideswipe same

direction.

Crashes Summary


After

Crashes B/C Ratio


5/9/2006 38

11/9/2006-

12/31/2008 14 1.04

SafetyAnalyst 2003-2005 18 (16) 2007 5 (5) -0.68 (-1.86)


34

Countermeasures

1. Traffic signals were installed in an attempt to reduce these crashes and

accommodate the high traffic volume.

Results Summary

1. Traffic volume of the minor road (Monitor St.) is not available and default value

of 1000 vehicles per day is used in SafetyAnalyst.





3. US-53 is a one-way street northbound. However, the evaluation in 2009 included

also the crashes that occurred at the intersection of Coperland Ave. and Monitor

St, which makes the analysis severely biased.

4. Almost all crashes are target crashes.

5. The negative B-C ratio based on the reduction of either all crashes or target

crashes shows that this project is not economically worthwhile.

35

Project 12: FOS 69960674 (WI-16, from MacFarlane Ln. to Dewitt St., Portage,

Columbia County)

FOS Region County Municipality Site Type Road From To Cost

69960674 SW Columbia Portage Segment WI-16/

Wisconsin St.

MacFarlane

Lane

Dewitt

St. $110,000


1. Since Portage is a very old city, the streets are narrow and intersect at odd angles.

The narrow, winding streets and outdated, uncoordinated traffic signals caused

extreme traffic backup even with the slightest increase in volume. Crash rates

were increased every year, mainly because of the backup issue.

2. The target crashes were rear end crashes only.

Crashes Summary


After

Crashes B/C Ratio

Evaluation 2009 7/12/2001-

7/12/2006 20

1/12/2006-

12/31/2008 10 1.58

SafetyAnalyst 2003-2005 15 (6) 2007 9 (2) -16.33 (-2.49)


36

Countermeasures

1. An update of the traffic signals at the MacFarlane, Cook, and DeWitt intersections

to include coordination were installed to alleviate the backup problem.

2. The traffic lights were replaced with modern designs.

Results Summary

1. In the analysis in 2009, the project was evaluated as three separate intersections in

the E.B. analysis and then combined for the B-C analyses. Therefore, segment

crashes were missed.

2. None of the minor roads is provided with traffic volumes in the dataset for

SafetyAnalyst; therefore, default value of 1000 vehicles per day is used in the

analysis.

3. In the analysis in 2009, the major and minor traffic volumes of the intersection of

Wisconsin St. and MacFarlane Lane are 7000 and 6400 respectively, for year

2001, with a growth factor 2%. In the dataset for SafetyAnalyst they are 9600 and

1000, for year 2007, and the growth factor is 4%.


Wisconsin St. and Cook St. are 10400 and 6750 respectively, for year 2001, with

a growth factor 2%. In the dataset for SafetyAnalyst they are 10200 and 1000, for

year 2007, and the growth factor is 4%.


Wisconsin St. and Dewitt St. are 10000 and 4900 respectively, for year 2001, with

a growth factor 2%. In the dataset for SafetyAnalyst they are 9620 and 1000, for

year 2007, and the growth factor is 4%.

6. Only a small portion of the crashes are target crashes. Based on these crashes, the

B-C ratio is negative, so the project is not economically worthwhile.

37

Project 13: FOS 69991072 (Bus. 51 & CTH XX, Rothschild, Marathon County)


69991072 NC Marathon Rothschild Intersection Bus. 51 CTH XX/

Imperial Ave. $217,000


1. SB 51 merged into 2 lanes from 4 just north of the intersection, causing a lot of

merging/weaving cars that lead to a lot of accidents involving the SB LT vehicles.

Also, because of grades, there was a sight distance problem for the same LT

vehicles.

2. The target crashes were angle and rear end crashes.

Crashes Summary


After

Crashes B/C Ratio


5/9/2006 97

11/9/2006-

12/31/2008 33 -1.19

SafetyAnalyst 2003-2005 51 (33) 2007 11 (7) 1.27 (1.03)


38

Countermeasures

1. Two additional through lanes in each direction, protected LT lanes in each

direction, and an extended NB RT lane were constructed to alleviate the problem.

Results Summary

1. Traffic volume of the minor road (Imperial Ave.) is not available and default

value of 1000 vehicles per day is used in SafetyAnalyst.

2. In the evaluation in 2009 the major and minor traffic volumes are 16800 and

15000 respectively, for year 2001, with a growth factor 2%. In the evaluation

using SafetyAnalyst they are 16800 (NB), 18600 (SB), and 1000 respectively, for

year 2007, with the growth factor being 4%.

3. This intersection is a four-leg intersection, but it is treated as two three-leg

intersections.

4. The B-C ratio calculated by SafetyAnalyst based on the reduction of target

crashes shows that this project is economically worthwhile. However, the

evaluation in 2009 resulted entirely opposite conclusion. This is because of the

huge difference of the minor road traffic volumes used in the two evaluations. In

addition, the earlier evaluation included also a few crashes far from the

intersection targeted.

39

Project 14: FOS 70300370 (US-10 & Grand Ave., Neillsville, Clark County)


70300370 NW Clark Neillsville Intersection US-10/

Division St.

WI-73/

Grand Ave. $456,000


1. A high LT volume from USH 10 West onto WI 73 South (50% of WB USH 10

approach volume) as well as a high number of truck turns in the intersection

resulted in a high number of crashes.

2. The target crashes were angle, no collision, and rear end crashes.

Crashes Summary


After

Crashes B/C Ratio

Evaluation 2009 3/14/2001-

3/14/2006 19

9/14/2006-

12/31/2008 5 0.33

SafetyAnalyst 2003-2005 4 (4) 2007 2 (2) 3.09 (3.15)


40

Countermeasures

1. Traffic signals were installed as the new traffic control.

2. Minor geometric changes (corner radii and turn bays) were implemented in order

to reduce the crash rates and improve safety.

Results Summary

1. Traffic volume of the minor road (Imperial Ave.) is not available and default

value of 1000 vehicles per day is used in SafetyAnalyst.





3. This intersection is a four-leg intersection, but it is treated a three-leg intersection

in the dataset for SafetyAnalyst.


crashes shows that this project is economically worthwhile. However, the

evaluation in 2009 resulted in a small ratio which is less than one. This is because

of the difference of the minor road traffic volumes used in the two evaluations.

5. In addition, the earlier evaluation included also a few crashes at the east

intersection of US-10 and WI-73.

41

Project 15: FOS 72200191 (WI-25 & Main St., Menominie, Dunn County)


72200191 NW Dunn Menominie Intersection WI-25/29/

S. Broadway St. Main St. $11,000


1. Traffic signals located in the SE quadrant of the intersection were conflicting with

large truck turning radii and many property damage crashes occurred when trucks

would hit the signals.

2. The target crashes were no collision crashes only.

Crashes Summary


After

Crashes B/C Ratio

Evaluation 2009 1/25/2001-

1/25/2006 62

7/25/2006-

12/31/2008 16 13.09

SafetyAnalyst 2003-2005 28 (0) 2007 4 (0) 29.88 (0)


42

Countermeasures

1. Since adjacent property and other objects prohibited increasing the turning radius,

the traffic signals were moved in order to provide more room for the turning

trucks.

Results Summary

1. Traffic volume of the minor road (Main St.) is not available and default value of

1000 vehicles per day is used in SafetyAnalyst.





3. This intersection is a four-leg intersection, but it is treated two three-leg

intersections in the dataset for SafetyAnalyst.


crashes shows that this project is economically worthwhile, which agrees with the

conclusion of HSIP evaluation 2009.

5. Because the naming of streets in this area is complicated which means that many

streets have multiple names, the evaluation in 2009 included also many crashes at

the other adjacent intersections.

43

Project 16: FOS 86100270 (WI-312 & Old Wells, Eau Claire, Eau Claire County)


86100270 NW Eau Claire Eau Claire Intersection WI-312/

North Crossing Old Wells $199,000


1. Substantial turn volumes between the East and South legs of the intersection

caused multiple crashes resulting in injuries.

2. The target crashes were angle and rear end crashes.

Crashes Summary


After

Crashes B/C Ratio

Evaluation 2009 6/13/2001-

6/13/2006 9

12/13/2006-

12/31/2008 8 1.71

SafetyAnalyst 2003-2005 6 (3) 2007 3 (2) 2.64 (1.45)


44

Countermeasures

1. The intersection was reconstructed to allow more storage volume for turning

vehicles as well as to be more pedestrian friendly.

2. Traffic signals were also installed to increase overall safety.

Results Summary

1. Traffic volume of the minor road (Main St.) is not available and default value of




SafetyAnalyst they are 10050 (EB), 13100 (WB), and 1000 respectively, for year





crashes shows that this project is economically worthwhile, which agrees with the

conclusion of HSIP evaluation 2009.

45

Project 17: FOS 86810571 (US-2 & Banks Ave., Superior, Douglas County)


86810571 NW Douglas Superior Intersection US-2/

Belknap St. Banks Ave. $334,000


1. EB traffic on Belknap St. used to be prohibited from LTs onto Banks Ave. Even

with this restriction, vehicles consistently attempted left turns at the signalized

intersection, causing a large percentage of the 87 crashes in five years. These

crashes were mostly caused by the limited sight distance vehicles have traveling

EB out of the Via Duct.

2. The target crashes were angle and rear end crashes only.

Crashes Summary


After

Crashes B/C Ratio

Evaluation 2009 2/14/2001-

2/14/2006 34

8/14/2006-

12/31/2008 14 1.44

SafetyAnalyst 2003-2005 NA 2007 NA NA

46

Countermeasures

3. An exclusive LT lane was installed for EB traffic on Belknap at Banks along with

a protected LT signal phase.

Results Summary

1. This intersection is missing in the dataset for SafetyAnalyst.

47

Project 18: FOS 92000371 (WI-29 & CTH VV, Howard, Brown County)


92000371 NE Brown Howard Intersection WI-29/32 CTH VV/

Triangle Dr. $347,000


1. A large meat market facility opened near the intersection, increasing truck traffic.

However, the 60' median was not wide enough to allow these large trucks to

complete a two stage gap acceptance maneuver, resulting in a large number of

angle crashes.

2. The target crashes were angle crashes only.

Crashes Summary


After

Crashes B/C Ratio

Evaluation 2009 6/13/2001-

6/13/2006 64

12/13/2006-

12/31/2008 10 2.00

SafetyAnalyst 2003-2005 25 (17) 2007 4 (4) -0.92 (-2.34)


48

Countermeasures

1. An offset WB RT lane was constructed to allow more visibility to SB vehicles

and an EB acceleration lane was added in the median to allow trucks to more

safely merge into the 65 mph traffic stream.

Results Summary

1. Traffic volume of the minor road (CTH VV) is not available and default value of








4. A large portion of crashes used in the early evaluation occurred at the other

intersections or road segments than the intersection targeted, which made the

analysis less reliable.


crashes shows that this project is not economically worthwhile, which is against

the conclusion from HSIP evaluation 2009. This is due to the difference of the

major road traffic volumes in the two analyses.

49

VI. CONCLUSIONS AND RECOMMENDATIONS

SafetyAnalyst is a state-of-the-art tool that standardizes and greatly simplifies the process

of highway safety assessment. When the relative data is available, SafetyAnalyst is able

to perform network screening, safety diagnosis, economic analysis of countermeasures,

and evaluation of projects. Compared with the earlier analyses, SafetyAnalyst streamlines

the entire procedure and reduces possibility of errors:

• Earlier HSIP projects evaluations were performed using an Excel tool. Each

project is stored in one Excel file which contains several sheets. The user needs to

update all files if any parameter is to be changed. This is a tedious job and prone

to errors. On the contrary, SafetyAnalyst stores all parameters in one place. In

addition, the Excel tool is not fully tested, while SafetyAnalyst has been tested by

several states and is still improving.

• In the earlier HSIP evaluations, the analyst needed to manually search for the

crashes by highway and street names and crash descriptions, for each project. This

is very time consuming and errors are almost unavoidable. SafetyAnalyst assigns

the crashes to the sites based on their coordinates provided by DOT, which is

more accurate.

In addition, SafetyAnalyst is capable of fitting the model parameters based on the data of

the agency. Models obtained this way are more consistent with the specific situation

compared with the federal models.

Compared to the evaluation in 2009, the analysis using SafetyAnalyst produces more or

less different results. Some of the results are even opposite to each other. There are a

couple of reasons behind this:

1. In the evaluation in 2009, almost all of them incorrectly included crashes not

relevant to the project and yet missed out some others that are relevant.

2. The biggest problem with the evaluation using SafetyAnalyst is lack of data and

data accuracy.

• SafetyAnalyst requires at least 3 years “before” data and 3 years “after” data

to reach reliable conclusions. However, only 1 year “after” data are available.

• Most of the projects are intersections. However, all the intersections lack

minor road traffic volume data and a default value of 1000 vehicles per day

has to be assumed in the analysis. This value is often far from truth. In

addition, the major road volumes are also more or less different than those

used in the earlier analysis, which might be due to the difference of data

sources.

• Two projects were located at freeway ramps. Although SafetyAnalyst is

capable of analyzing ramps separately, data is not available in the dataset

50

provided by WisDOT. For example, it is hard to decide if a crash occurred on

the ramp or the highway without examining the crash report.

• Some accidents are incorrectly assigned. This might be a software issue.

• In the data provided by WisDOT, many 4-leg intersections are divided into

two 3-leg intersections.

3. Possible software issue with SafetyAnalyst: some accidents are incorrectly

assigned.

Finally, some software bugs show up during our assessment of SafetyAnalyst. We have

reported them and a few of them have been fixed by the developers.

51

APPENDIX 1: RESULTS OF NETWORK SCREENING

Table A.1 — 5% Screening of SW Region Intersections

ID Site Subtype County Route Minor Road

Location with Highest Potential for Safety Improvement

Rank Average

Observed

Accidents*

Predicted

Accident

Frequency*

Expected

Accident

Frequency*

Variance**

C|018E|012253|096520 Int/Urb; 4-leg signalized DANE US018E CTH PD 17.77 3.45 15.49 2.72 1

C|051N|015498|049660 Int/Urb; 4-leg signalized DANE US051N CTH AB 13.38 3.64 11.9 2.11 2

C|051S|015634|072320 Int/Urb; 4-leg minor-rd STOP DANE US051S CTH BW 13.08 1.22 11.11 1.93 3

C|018W|014097|016440 Int/Urb; 3-leg minor-rd STOP DANE US018W MCKEE RD 15.16 0.38 10.69 1.57 4

C|051N|012655|051920 Int/Urb; 3-leg minor-rd STOP DANE US051N ON RAMP TO STH 13.69 0.39 9.72 1.44 5

C|035N|003892|077160 Int/Urb; 4-leg signalized LA CROSSE SR035N STATE ST 11.08 2.77 9.49 1.61 6

C|012E|015586|255210 Int/Urb; 3-leg minor-rd STOP DANE US012E ON RAMP FROM CT 11.58 0.6 9.2 1.52 7

C|051S|011047|070560 Int/Urb; 4-leg minor-rd STOP DANE US051S BUCKEYE RD 10.8 1.16 9.14 1.57 8

C|157E|009759|002160 Int/Urb; 4-leg minor-rd STOP LA CROSSE SR157E STH 16 WB 10.59 1.01 8.75 1.47 9

C|033E|003563|001790 Int/Urb; 4-leg signalized LA CROSSE SR033E LOSEY BLVD S 10.03 2.44 8.43 1.39 10

C|051N|011946|014360 Int/Urb; 4-leg signalized ROCK US051N BEGIN NEW PROJE 8.99 2.1 7.35 1.17 11

C|016E|001608|004290 Int/Urb; 4-leg signalized LA CROSSE SR016E GILLETTE ST 8.15 3.27 7.34 1.28 12

C|157E|009759|002050 Int/Urb; 3-leg signalized LA CROSSE SR157E CTH PH 8.25 3.01 6.97 1.18 13

C|014W|010557|003480 Int/Urb; 4-leg minor-rd STOP ROCK US014W LEXINGTON DR 8.3 1 6.88 1.15 14

C|014E|001563|159270 Int/Urb; 3-leg signalized ROCK US014E DEERFIELD DR 9.15 2.05 6.87 1.04 15

C|151S|018199|071780 Int/Urb; 4-leg minor-rd STOP DANE US151S ZIER RD 7.68 1.17 6.57 1.13 16

C|151N|018194|048550 Int/Urb; 4-leg signalized DANE US151N ZIER RD 6.9 3.52 6.37 1.12 17

C|035N|003894|077480 Int/Urb; 4-leg signalized LA CROSSE SR035N LACROSSE ST 7.32 2.51 6.32 1.05 18

C|018W|012256|015800 Int/Urb; 4-leg minor-rd STOP DANE US018W WILLIAMSBURG WA 7.27 1.19 6.24 1.08 19

C|113S|014853|004310 Int/Urb; 4-leg minor-rd STOP DANE SR113S SHERMAN AVE 7.27 1.07 6.13 1.04 20

52

C|018W|012256|015170 Int/Urb; 3-leg minor-rd STOP DANE US018W RAYMOND RD 8.21 0.44 6.08 0.93 21

C|151N|015339|047940 Int/Urb; 3-leg minor-rd STOP DANE US151N PORTAGE RD 8.21 0.41 5.99 0.9 22

C|012E|019987|203670 Int/Rur; 3-leg signalized SAUK US012E WHITLOCK ST 6.74 2.65 5.83 1.13 23

C|051N|005367|047900 Int/Urb; 4-leg signalized DANE US051N CTH BW 6.06 3.54 5.67 1 24

C|012E|017440|213190 Int/Urb; 4-leg signalized SAUK US012E CTH W 6.48 2.19 5.49 0.88 25

C|035N|003892|077080 Int/Urb; 4-leg signalized LA CROSSE SR035N MAIN ST 6.06 2.77 5.43 0.92 26

C|081E|017105|089280 Int/Urb; 4-leg minor-rd STOP ROCK SR081E PORTLAND AVE 6.64 0.9 5.43 0.89 27

C|151S|014963|075530 Int/Urb; 3-leg minor-rd STOP DANE US151S STH 113 NB 6.95 0.46 5.24 0.81 28

C|012E|000982|202860 Int/Rur; 4-leg signalized SAUK US012E LAKE AVE 5.89 2.47 5.19 0.87 29

C|151N|014919|039540 Int/Urb; 4-leg signalized DANE US151N BADGER RD 5.64 3.01 5.17 0.89 30

C|026N|017087|002560 Int/Urb; 4-leg signalized ROCK SR026N MILTON AVE SER 5.64 2.88 5.13 0.87 31

C|151N|015341|048230 Int/Urb; 3-leg signalized DANE US151N EAGAN RD 5.35 4.13 5.12 0.93 32

C|151S|014931|079420 Int/Urb; 3-leg signalized DANE US151S FISH HATCHERY R 5.13 5.06 5.12 0.96 33

C|014W|019098|026060 Int/Urb; 4-leg minor-rd STOP LA CROSSE US014W 4TH ST 6.23 0.88 5.07 0.83 34

C|019E|012774|027450 Int/Urb; 3-leg signalized DANE SR019E BROADWAY DR 6.02 2.55 5.06 0.82 35

C|012E|017437|212170 Int/Urb; 3-leg signalized SAUK US012E STH 33 EB 6.25 2.25 5.04 0.79 36

Table A.2 — 5% Screening of SW Region Segments

ID Site Subtype County Route Site Start

Location

Site End

Location

Average

Observed

Accidents for

Entire Site*


Rank Average

Observed

Accidents*

Predicted

Accident

Frequency*

Expected

Accident

Frequency*

Variance** Start

Location

End

Location

S015620 Seg/Urb; Fwy in intchng area (6 ln) DANE US012E 255.9 255.91 546.22 546.22 30.18 269.07 26.17 255.9 255.91 1

S015579 Seg/Urb; Fwy (4 ln) DANE US012E 251.66 253.07 24.27 124.61 11.17 106.42 18.87 252.86 252.96 2




53




S018200 Seg/Urb; Fwy (8+ ln) DANE I039N 49.71 49.72 144.31 144.31 17.19 58.57 3.06 49.71 49.72 9

S005537 Seg/Urb; One-way arterial LA CROSSE US053N 0.34 0.41 60.93 60.93 10.15 51.86 9.08 0.34 0.41 10

S015627 Seg/Urb; Fwy (6 ln) DANE US012E 257.33 258.04 18.96 58.63 19.28 51.15 9 257.94 258.04 11

S005346 Seg/Urb; 2-lane arterial DANE US051N 35.76 35.96 35.29 50.41 6.65 47.59 8.98 35.76 35.86 12






S001964 Seg/Urb; 2-lane arterial DANE SR019E 16.03 16.37 17.2 40.33 7.3 38.38 7.28 16.03 16.13 18





S001613 Seg/Urb; 2-lane arterial LA CROSSE SR016E 9.37 10.81 6.72 36.29 6.89 34.46 6.52 9.37 9.47 23


S011064 Seg/Urb; One-way arterial LA CROSSE US053S 156.7 156.99 27.21 36.25 11.48 33.31 6.26 156.8 156.9 25




S015460 Seg/Urb; Fwy in intchng area (4 ln) ROCK I039N 2.46 2.54 37.46 37.46 10.35 30.9 5.01 2.46 2.54 29


S012300 Seg/Urb; 2-lane arterial JEFFERSON SR026N 41.13 41.32 19.1 32.26 6.7 30.63 5.78 41.13 41.23 31

54


S015556 Seg/Urb; Fwy (6 ln) DANE I039S 135.66 136.97 11.27 34.74 14.52 29.94 4.96 136.87 136.97 33

S015567 Seg/Urb; Fwy (4 ln) DANE I039N 43.15 44.52 9.56 35.9 6.53 28.67 4.56 43.75 43.85 34

S002034 Seg/Urb; 2-lane arterial JEFFERSON SR019E 56.09 56.14 32.26 32.26 5.81 28.65 4.99 56.09 56.14 35



S015441 Seg/Urb; Fwy (4 ln) ROCK I039S 165.21 166.18 9.36 35.9 5.57 27.51 4.2 166.08 166.18 38








S002031 Seg/Urb; 2-lane arterial JEFFERSON SR019E 55.9 56 26.21 26.21 6.91 25.01 4.73 55.9 56 46

S003908 Seg/Urb; 2-lane arterial LA CROSSE SR035N 80.32 80.44 23.52 26.21 6.61 24.94 4.7 80.34 80.44 47



S015473 Seg/Urb; Fwy (4 ln) ROCK I039N 16.4 17.37 9.36 31.68 5.57 24.45 3.73 16.4 16.5 50


S015552 Seg/Urb; Fwy in intchng area (6 ln) DANE I039S 132.61 132.71 25.21 25.21 18.58 24.16 4.27 132.61 132.71 52



S011971 Seg/Urb; 2-lane arterial RICHLAND SR080N 66.36 66.42 26.88 26.88 4.46 23.6 4.06 66.36 66.42 55



55

S017105 Seg/Urb; 2-lane arterial ROCK SR081E 89.28 89.59 16.26 24.2 7.67 23.26 4.43 89.28 89.38 58

S015546 Seg/Urb; Fwy in intchng area (6 ln) DANE US151N 49.48 50.02 5.84 27.31 10.68 23.2 3.67 49.92 50.02 59

S006298 Seg/Urb; 2-lane arterial SAUK SR060E 64.57 65.02 8.51 24.2 5.43 22.74 4.23 64.57 64.67 60




S015225 Seg/Urb; Fwy (4 ln) LA CROSSE I090W 105.58 105.93 13.28 31.68 4.3 22.6 3.19 105.83 105.93 64



S012927 Seg/Urb; 2-lane arterial LA CROSSE US014E 7.17 8.55 7.31 24.2 3.65 21.91 3.92 7.97 8.07 67

S015135 Seg/Urb; Fwy (4 ln) DANE SR030E 0 1.2 6.51 29.57 4.75 21.88 3.19 0 0.1 68










S010581 Seg/Urb; One-way arterial CRAWFORD US018W 58.22 58.41 14.59 23.46 6.83 20.39 3.55 58.22 58.32 78

S010585 Seg/Urb; One-way arterial CRAWFORD US018W 58.14 58.22 21.33 21.33 13.17 20.28 3.77 58.14 58.22 79




56

S010506 Seg/Urb; One-way arterial JEFFERSON US012W 36.99 37.33 13.17 21.33 9.89 19.78 3.65 36.99 37.09 83


S015191 Seg/Urb; 2-lane arterial LA CROSSE US053N 3.75 4.35 6.05 20.16 6.95 19.35 3.66 3.75 3.85 85

S002856 Seg/Urb; 2-lane arterial MONROE SR027N 65.44 65.69 9.68 20.16 6.86 19.33 3.65 65.59 65.69 86




S015454 Seg/Urb; Fwy (4 ln) ROCK I039S 177.17 177.78 9 23.23 6.36 18.99 3 177.68 177.78 90



S014556 Seg/Urb; Fwy (6 ln) DANE US151N 51.48 52.81 3.27 23.89 9.06 18.95 2.74 52.71 52.81 93

S018201 Seg/Urb; Fwy (8+ ln) DANE I039N 49.72 49.82 19.24 19.24 17.19 18.89 2.51 49.72 49.82 94





S015217 Seg/Urb; Fwy (4 ln) LA CROSSE I090E 1.96 2.43 7.19 27.46 3.56 18.49 2.44 1.96 2.06 99






S011934 Seg/Urb; 2-lane arterial SAUK US012E 210.55 210.92 7.08 18.15 8.35 17.64 3.37 210.55 210.65 105



S000996 Seg/Urb; 2-lane arterial JEFFERSON US012E 286.21 286.88 6.32 18.15 6.44 17.37 3.27 286.51 286.61 108

57

S005177 Seg/Urb; 2-lane arterial DODGE SR049N 15.35 15.6 10.48 18.15 6.32 17.35 3.26 15.5 15.6 109

S015557 Seg/Urb; Fwy (4 ln) DANE US012E 261.5 261.8 10.56 19.01 9.68 17.32 3 261.7 261.8 110







S019377 Seg/Urb; Fwy (4 ln) ROCK I039N 0 1.17 7.76 21.12 5.9 17.08 2.65 0.2 0.3 117






S003677 Seg/Urb; 2-lane arterial COLUMBIA SR033E 103.94 104.4 7.89 18.15 4.37 16.84 3.07 104.24 104.34 123

S014588 Seg/Urb; Fwy (4 ln) DANE US151S 65.02 66.37 3.44 25.34 3.34 16.77 2.16 66.27 66.37 124



S000984 Seg/Rur; 2-lane SAUK US012E 207.03 208.03 9.61 32.02 3.44 16.65 1.54 207.93 208.03 127



S015144 Seg/Urb; Fwy (4 ln) DANE SR030W 1.37 1.91 6.26 21.12 5.08 16.38 2.44 1.81 1.91 130




S001402 Seg/Rur; 2-lane VERNON US014E 16.75 17.26 16.09 42.03 2.09 15.77 1.08 16.85 16.95 134

58



S011568 Seg/Urb; One-way arterial COLUMBIA US051N 85.64 86.16 7.79 17.06 8.43 15.72 2.83 85.74 85.84 137


S001508 Seg/Rur; 2-lane DANE US014E 107.3 108.54 6.3 32.02 3.03 15.51 1.34 107.4 107.5 139

S002094 Seg/Urb; 2-lane arterial MONROE SR021E 0.3 0.37 17.28 17.28 4.09 15.46 2.69 0.3 0.37 140



S003721 Seg/Urb; 2-lane arterial DODGE SR033E 140.61 140.68 17.28 17.28 3.73 15.26 2.62 140.61 140.68 143



S017400 Seg/Urb; 2-lane arterial RICHLAND SR080N 64.99 65.11 15.12 18.15 1.92 15.02 2.44 64.99 65.09 146






S012083 Seg/Rur; 2-lane JEFFERSON SR026N 16.53 17.01 8.76 32.02 2.73 14.61 1.19 16.91 17.01 152






S015223 Seg/Urb; Fwy (6 ln) LA CROSSE I090W 103.79 104.36 5.71 19.54 6.3 14.01 1.77 104.26 104.36 158

S015199 Seg/Urb; Fwy (4 ln) LA CROSSE US053N 8.59 10.16 2.82 25.34 2.22 14 1.51 10.06 10.16 159

S013837 Seg/Urb; Fwy (4 ln) DANE I094E 151.38 151.59 10.06 16.9 5.82 13.92 2.15 151.49 151.59 160

59


S018304 Seg/Urb; 2-lane arterial ROCK US051N 12.68 12.91 11.4 14.11 8.24 13.8 2.64 12.81 12.91 162

S009331 Seg/Urb; One-way arterial DANE SR138N 11.98 12.26 6.85 14.93 7.93 13.79 2.46 12.16 12.26 163



S005178 Seg/Urb; 2-lane arterial DODGE SR049N 15.6 16.56 6.3 14.11 6.63 13.63 2.57 16.3 16.4 166


S003829 Seg/Urb; 2-lane arterial CRAWFORD SR035N 21.61 21.92 7.81 14.11 5.8 13.51 2.52 21.61 21.71 168



S011954 Seg/Urb; 2-lane arterial ROCK US051N 16.44 17.47 5.48 14.11 5.37 13.43 2.49 16.94 17.04 171

S015625 Seg/Urb; Fwy in intchng area (6 ln) DANE US012E 257.23 257.26 7 7 29.6 13.39 2.02 257.23 257.26 172





S002706 Seg/Urb; 2-lane arterial ROCK SR026N 0 0.44 7.79 14.11 4.69 13.28 2.44 0 0.1 177


S014590 Seg/Urb; Fwy (6 ln) DANE US151S 67.5 68.82 3.45 15.2 9.06 13.15 1.9 67.5 67.6 179

S015367 Seg/Rur; Fwy (4 ln) SAUK I090E 90.54 92.13 9.29 43.44 3.9 13.15 0.67 92.03 92.13 180


S019370 Seg/Rur; Fwy (4 ln) DANE I039N 35.35 35.87 11.28 34.75 4.81 13 0.77 35.77 35.87 182





60


S013849 Seg/Urb; Fwy (4 ln) JEFFERSON I094E 164.09 165.35 5.36 16.9 4.48 12.89 1.84 165.25 165.35 188

S013850 Seg/Urb; Fwy (4 ln) JEFFERSON I094E 165.35 166.56 5.93 16.9 4.48 12.89 1.84 165.55 165.65 188

S002457 Seg/Urb; 2-lane arterial SAUK SR023E 69.65 70.16 5.93 14.11 3.51 12.89 2.3 70.05 70.15 190


S012053 Seg/Rur; 2-lane LA CROSSE SR035N 73.99 74.64 9.55 26.02 2.96 12.75 1.08 74.09 74.19 192






S014557 Seg/Urb; Fwy (4 ln) DANE US151N 52.81 53.94 3.74 16.9 4.14 12.56 1.75 53.84 53.94 198

S015368 Seg/Rur; Fwy in intchng area (4 ln) SAUK I090E 92.13 92.91 6.97 26.25 5.97 12.52 0.76 92.13 92.23 199

S019101 Seg/Urb; One-way arterial LA CROSSE US014E 1.78 2 6.79 12.8 10.1 12.44 2.3 1.78 1.88 200


S013395 Seg/Urb; Fwy (4 ln) DANE I094W 102.18 102.42 9.68 14.78 5.82 12.38 1.91 102.28 102.38 202

S013877 Seg/Urb; Fwy (4 ln) DANE I094W 99.69 100.55 5.16 14.78 5.82 12.38 1.91 100.09 100.19 202

S010547 Seg/Urb; One-way arterial LA CROSSE US014W 26.13 26.21 13.33 13.33 7.92 12.27 2.1 26.13 26.21 204

S001407 Seg/Rur; 2-lane VERNON US014E 18.58 19.14 11.08 32.02 2.03 12.14 0.82 19.04 19.14 205

S018197 Seg/Urb; Fwy in intchng area (6 ln) DANE US151S 70.84 71.03 8.85 12.61 10.68 12.13 1.92 70.93 71.03 206



S014982 Seg/Rur; 2-lane GREEN SR011E 53.26 53.92 6.07 30.02 2.16 11.93 0.84 53.36 53.46 209



S019369 Seg/Rur; Fwy (4 ln) DANE I039N 34.68 35.35 12.32 30.41 4.81 11.82 0.7 34.78 34.88 212

61


S005553 Seg/Rur; 2-lane LA CROSSE US053N 17.31 18.31 7.41 26.02 2.59 11.78 0.93 17.31 17.41 214










S018583 Seg/Urb; Fwy (4 ln) MONROE I094E 143.09 144.52 5.61 16.9 3.31 11.57 1.49 143.59 143.69 224


S015215 Seg/Urb; Fwy in intchng area (4 ln) LA CROSSE I090E 2.43 2.87 8.27 14.98 5.04 11.57 1.62 2.73 2.83 226



S013860 Seg/Urb; Fwy (4 ln) JEFFERSON I094W 84.11 85.34 4.46 14.78 4.48 11.46 1.64 84.21 84.31 229

S013861 Seg/Urb; Fwy (4 ln) JEFFERSON I094W 85.34 86.59 4.56 14.78 4.48 11.46 1.64 86.49 86.59 229

S015518 Seg/Rur; Fwy (6+ ln) COLUMBIA I039S 114.59 116.09 6.61 35.23 5.81 11.45 0.48 114.59 114.69 231

S006301 Seg/Urb; 2-lane arterial SAUK SR060E 65.63 66 6.54 12.1 4.58 11.41 2.09 65.83 65.93 232



S014189 Seg/Rur; Fwy in intchng area (4 ln) DODGE US041N 42.85 43.55 8.3 26.25 5.15 11.3 0.62 42.95 43.05 235

S008347 Seg/Urb; 2-lane arterial JEFFERSON SR089N 23.68 23.79 11 12.1 3.99 11.26 2.04 23.68 23.78 236

S001977 Seg/Urb; 2-lane arterial DANE SR019E 23.28 23.61 6.72 12.1 3.63 11.15 2 23.51 23.61 237


62

Table A.3 — 5% Screening of SE Region Intersections



Rank Average

Observed

Accidents*

Predicted

Accident

Frequency*

Expected

Accident

Frequency*

Variance**

C|018E|001922|144500 Int/Urb; 4-leg signalized WAUKESHA US018E CTH Y 37.21 3.51 31.92 5.63 1

C|018E|001927|147570 Int/Urb; 3-leg signalized WAUKESHA US018E CTH O 22.53 3.32 18.19 3.14 2

C|018E|001923|145520 Int/Urb; 4-leg signalized WAUKESHA US018E BROOKFIELD RD 17.56 3.45 15.31 2.69 3

C|018E|018493|155250 Int/Urb; 4-leg signalized MILWAUKEE US018E WISCONSIN AVE E 15.47 2.39 12.66 2.08 4

C|050E|005304|039490 Int/Urb; 4-leg signalized KENOSHA SR050E 88TH AVE 14.63 3.11 12.63 2.18 5

C|190E|010258|015410 Int/Urb; 4-leg signalized MILWAUKEE SR190E N 35TH ST 14.42 3.25 12.55 2.18 6

C|031N|003232|006170 Int/Urb; 4-leg signalized KENOSHA SR031N CTH K 14.01 3.06 12.08 2.08 7

C|033E|003765|176000 Int/Urb; 4-leg signalized WASHINGTON SR033E RIVER RD 15.05 2.13 12.02 1.92 8

C|059E|016887|100830 Int/Urb; 3-leg signalized WAUKESHA SR059E CTH O 15.84 2.32 11.85 1.86 9

C|018E|017868|143870 Int/Urb; 3-leg signalized WAUKESHA US018E SWENSON DR 13.16 4.74 11.73 2.17 10

C|020E|002091|041870 Int/Urb; 4-leg signalized RACINE SR020E WISCONSIN AVE 15.26 1.45 10.98 1.58 11

C|145N|009491|002570 Int/Urb; 4-leg signalized MILWAUKEE SR145N N 27TH ST 13.17 2.35 10.81 1.77 12

C|100N|008660|011320 Int/Urb; 4-leg signalized MILWAUKEE SR100N CTH T 12.33 3.12 10.74 1.86 13

C|100N|008680|017160 Int/Urb; 4-leg signalized MILWAUKEE SR100N W NORTH AVE 12.12 2.97 10.47 1.79 14

C|241N|004399|008330 Int/Urb; 4-leg signalized MILWAUKEE SR241N CTH Y 11.71 3.33 10.33 1.81 15

C|158E|009772|006030 Int/Urb; 4-leg signalized KENOSHA SR158E AUTO WORKERS AV 12.33 2.44 10.24 1.69 16

C|038N|004233|016740 Int/Urb; 4-leg signalized MILWAUKEE SR038N DREXEL AVE 11.71 2.78 10.01 1.7 17

C|190E|010237|006810 Int/Urb; 4-leg signalized WAUKESHA SR190E CALHOUN RD 11.29 3.17 9.9 1.72 18

C|100N|008667|013190 Int/Urb; 4-leg signalized MILWAUKEE SR100N W LINCOLN AVE 10.66 3.41 9.5 1.67 19

C|018E|001919|140480 Int/Urb; 4-leg signalized WAUKESHA US018E SAINT PAUL AVE 11.71 2.1 9.42 1.5 20


63

C|031N|003246|017340 Int/Urb; 4-leg signalized RACINE SR031N SPRING ST 10.66 3.1 9.34 1.61 22

C|031S|010757|006380 Int/Urb; 3-leg signalized RACINE SR031S REGENCY MALL SO 10.93 3.35 9.23 1.6 23

C|059E|006251|106250 Int/Urb; 4-leg signalized MILWAUKEE SR059E S 70TH ST 11.08 2.37 9.19 1.51 24

C|018E|019118|141650 Int/Urb; 3-leg signalized WAUKESHA US018E STH 164 NB 11.6 2.59 9.15 1.49 25

C|057N|018504|001150 Int/Urb; 4-leg signalized MILWAUKEE SR057N W WISCONSIN AVE 10.87 2.26 8.94 1.45 26

C|031N|003238|014780 Int/Urb; 3-leg signalized RACINE SR031N N REGENCY MALL 10.04 4.15 8.92 1.61 27

C|031N|003236|007710 Int/Urb; 4-leg signalized KENOSHA SR031N CTH S (EB) 10.24 2.84 8.86 1.51 28

C|011E|000745|144600 Int/Urb; 3-leg signalized RACINE SR011E WILLOW RD 10.49 3.28 8.84 1.52 29


C|181N|010156|009330 Int/Urb; 4-leg signalized MILWAUKEE SR181N CTH PP 10.03 2.67 8.58 1.44 31

C|100N|017210|024770 Int/Urb; 3-leg signalized MILWAUKEE SR100N SWAN RD 9.82 3.76 8.57 1.52 32

C|031N|003238|014630 Int/Urb; 3-leg signalized RACINE SR031N S REGENCY MALL 9.59 4.15 8.56 1.55 33

C|100N|008664|012580 Int/Urb; 4-leg signalized MILWAUKEE SR100N W NATIONAL AVE 9.62 3.21 8.53 1.48 34

C|059E|012822|092780 Int/Urb; 4-leg signalized WAUKESHA SR059E STH 164 NB (S 10.03 2.47 8.45 1.4 35

C|018E|020716|157050 Int/Urb; 4-leg minor-rd STOP MILWAUKEE US018E W KILBOURN AVE 10.8 0.78 8.44 1.34 36

C|181N|010138|002270 Int/Urb; 3-leg signalized MILWAUKEE SR181N HARMONEE AVE 11.16 2.12 8.32 1.27 37

C|018E|001922|144600 Int/Urb; 3-leg signalized WAUKESHA US018E ENTRANCE TO ZOR 8.92 4.98 8.28 1.55 38

C|059E|006257|109740 Int/Urb; 4-leg signalized MILWAUKEE SR059E CESAR E. CHAVEZ 9.83 2.43 8.26 1.36 39

C|038N|004220|002750 Int/Urb; 3-leg signalized RACINE SR038N GREEN BAY RD 11.38 1.95 8.24 1.23 40

C|057N|006044|009670 Int/Urb; 4-leg signalized MILWAUKEE SR057N CTH PP 10.03 2.18 8.22 1.32 41


C|158W|018885|001330 Int/Urb; 4-leg signalized KENOSHA SR158W AUTO WORKERS AV 9.41 2.57 8.02 1.34 43

C|100N|008667|013950 Int/Urb; 3-leg signalized MILWAUKEE SR100N ENT SAM'S CLUB 8.7 4.67 8.01 1.48 44

C|041N|004409|002790 Int/Urb; 4-leg signalized MILWAUKEE US041N W CENTER ST 9.41 2.51 7.98 1.32 45

C|011E|000745|145150 Int/Urb; 3-leg signalized RACINE SR011E OAKES RD 9.37 3.28 7.98 1.37 46

C|024E|002597|006600 Int/Urb; 4-leg signalized MILWAUKEE SR024E S 43RD ST 9.83 2.05 7.95 1.26 47

C|036N|018133|008510 Int/Urb; 3-leg signalized RACINE SR036N CONGRESS ST 10.26 2.33 7.93 1.25 48

64

C|018W|010612|010790 Int/Urb; 4-leg signalized WAUKESHA US018W BARKER RD 8.78 3.3 7.87 1.37 49

C|059E|006243|094780 Int/Urb; 4-leg signalized WAUKESHA SR059E RACINE AVE 8.78 3.29 7.87 1.37 50

C|031N|018077|009230 Int/Urb; 4-leg signalized KENOSHA SR031N CTH L 9.41 2.34 7.87 1.29 51


C|031N|003228|005030 Int/Urb; 3-leg minor-rd STOP KENOSHA SR031N 76TH ST 11.37 0.35 7.84 1.12 53

C|020E|002070|035160 Int/Urb; 3-leg signalized RACINE SR020E FRANCHER RD 9.37 2.99 7.81 1.31 54

C|060E|017511|142390 Int/Urb; 4-leg signalized OZAUKEE SR060E CTH V 9.2 2.47 7.79 1.29 55

C|067N|007001|056360 Int/Urb; 4-leg signalized WAUKESHA SR067N VALLEY RD 8.99 2.74 7.79 1.31 56

C|038N|004231|015740 Int/Urb; 4-leg signalized MILWAUKEE SR038N PUETZ RD 8.99 2.72 7.77 1.31 57

C|031N|003240|015570 Int/Urb; 4-leg signalized RACINE SR031N 16TH ST 8.57 3.25 7.68 1.34 58

C|190E|010253|014380 Int/Urb; 4-leg signalized MILWAUKEE SR190E N 51ST BLVD 8.78 2.86 7.68 1.31 59

C|100N|008663|012200 Int/Urb; 4-leg signalized MILWAUKEE SR100N W OKLAHOMA AVE 8.57 3.21 7.67 1.33 60

C|181N|010154|008320 Int/Urb; 4-leg signalized MILWAUKEE SR181N W MILL RD 8.78 2.73 7.61 1.28 61

C|018W|017871|010690 Int/Urb; 3-leg signalized WAUKESHA US018W ENTRANCE TO WES 8.03 4.98 7.54 1.41 62

C|031N|018079|010250 Int/Urb; 4-leg signalized KENOSHA SR031N CTH E 8.78 2.45 7.45 1.23 63


C|018E|001934|150660 Int/Urb; 4-leg signalized MILWAUKEE US018E STH 100 NB 8.57 2.5 7.31 1.21 65

C|241N|004403|010360 Int/Urb; 4-leg signalized MILWAUKEE SR241N W OKLAHOMA AVE 8.36 2.78 7.3 1.24 66

C|011E|000742|143910 Int/Urb; 4-leg signalized RACINE SR011E 90TH ST 8.57 2.36 7.23 1.18 67

C|057N|006030|002680 Int/Urb; 4-leg signalized MILWAUKEE SR057N W NORTH AVE 9.2 1.7 7.11 1.07 68

C|190E|010235|005770 Int/Urb; 4-leg signalized WAUKESHA SR190E BROOKFIELD RD 7.94 3.08 7.09 1.22 69

C|050E|005306|041770 Int/Urb; 3-leg signalized KENOSHA SR050E COOPER RD 8.03 3.57 7.08 1.24 70

C|059E|016590|104320 Int/Urb; 4-leg signalized MILWAUKEE SR059E S 101ST ST 7.94 2.93 7.03 1.2 71


C|031N|003238|015050 Int/Urb; 4-leg signalized RACINE SR031N 21ST ST 7.73 3.24 6.98 1.21 73

C|032N|003303|031960 Int/Urb; 4-leg signalized MILWAUKEE SR032N E COLLEGE AVE 9.62 1.38 6.96 0.99 74

C|038N|004235|018750 Int/Urb; 4-leg signalized MILWAUKEE SR038N CTH ZZ 7.94 2.76 6.95 1.18 75

65

C|018E|001920|140690 Int/Urb; 4-leg signalized WAUKESHA US018E BARSTOW ST 8.36 2.14 6.91 1.11 76

C|038N|004211|000980 Int/Urb; 3-leg signalized RACINE SR038N SPRING ST 10.49 1.46 6.89 0.92 77

C|175N|010030|003680 Int/Urb; 3-leg signalized WAUKESHA SR175N CTH YY 8.92 2.22 6.88 1.07 78

C|011E|000750|146930 Int/Urb; 3-leg signalized RACINE SR011E MEACHEM RD 8.7 2.38 6.87 1.09 79


C|038N|004244|022770 Int/Urb; 4-leg signalized MILWAUKEE SR038N OKLAHOMA AVE 8.36 2.03 6.82 1.08 81

C|018E|017870|144410 Int/Urb; 3-leg signalized WAUKESHA US018E CTH JJ (EB) 7.36 4.31 6.8 1.24 82

C|020E|002073|036920 Int/Urb; 4-leg signalized RACINE SR020E OAKES RD 7.53 3.14 6.77 1.17 83

C|033E|017069|173250 Int/Urb; 3-leg signalized WASHINGTON SR033E WILDWOOD RD 8.03 2.86 6.72 1.12 84

C|074E|017653|010620 Int/Urb; 4-leg signalized WAUKESHA SR074E PILGRIM RD (CTH 7.94 2.19 6.62 1.07 85

C|020E|002075|037670 Int/Urb; 4-leg signalized RACINE SR020E EMMERTSEN RD 7.32 3.04 6.56 1.13 86

C|032N|003282|018270 Int/Urb; 4-leg signalized RACINE SR032N GOOLD AVE 7.73 2.3 6.53 1.06 87

C|018E|019116|141450 Int/Urb; 3-leg signalized WAUKESHA US018E CTH F 7.59 3.06 6.49 1.1 88



C|038N|004234|017740 Int/Urb; 4-leg signalized MILWAUKEE SR038N E RAWSON AVE 7.32 2.64 6.39 1.07 91

C|057N|018503|000980 Int/Urb; 4-leg signalized MILWAUKEE SR057N W CLYBOURN ST 7.53 2.26 6.35 1.03 92

C|059E|006256|108990 Int/Urb; 4-leg signalized MILWAUKEE SR059E S LAYTON BLVD 7.11 2.76 6.28 1.06 93

C|059E|006256|109420 Int/Urb; 4-leg signalized MILWAUKEE SR059E S 21ST ST 7.11 2.76 6.28 1.06 93

C|145N|009495|003990 Int/Urb; 3-leg minor-rd STOP MILWAUKEE SR145N CROSSOVER 8.84 0.37 6.26 0.92 95

C|181N|010129|000000 Int/Urb; 4-leg signalized MILWAUKEE SR181N STH 59 EB 7.32 2.31 6.21 1.01 96

C|018E|019128|143670 Int/Urb; 4-leg minor-rd STOP WAUKESHA US018E PARKLAWN RD 7.27 1.16 6.21 1.07 97

C|059E|006242|094020 Int/Urb; 4-leg signalized WAUKESHA SR059E SUNSET DR 6.9 2.84 6.14 1.04 98

C|011E|013076|147840 Int/Urb; 4-leg signalized RACINE SR011E TAYLOR ST 7.32 2.15 6.11 0.98 99

C|145N|009499|004940 Int/Urb; 4-leg signalized MILWAUKEE SR145N W MAXWELL PL 6.9 2.75 6.1 1.03 100

C|045N|017931|033970 Int/Urb; 3-leg minor-rd STOP MILWAUKEE US045N MAINTENANCE CRO 8.21 0.42 6.02 0.91 101

C|033E|003758|174810 Int/Urb; 3-leg signalized WASHINGTON SR033E STH 144 NB 7.81 2.09 6 0.91 102

66



C|057N|017784|012550 Int/Urb; 3-leg signalized MILWAUKEE SR057N ENTRANCE TO KOH 8.03 1.86 5.91 0.87 105

C|031N|003244|016180 Int/Urb; 3-leg signalized RACINE SR031N NEWMAN RD 6.92 2.9 5.91 0.99 106

C|190E|010241|009570 Int/Urb; 3-leg signalized WAUKESHA SR190E N 128TH ST 6.25 4.34 5.9 1.08 107

C|033E|017072|174000 Int/Urb; 4-leg signalized WASHINGTON SR033E 18TH AVE 6.69 2.64 5.89 0.99 108

C|060E|017506|142060 Int/Urb; 4-leg signalized OZAUKEE SR060E WASHINGTON ST 6.69 2.57 5.85 0.98 109

C|018E|018496|155640 Int/Urb; 3-leg signalized MILWAUKEE US018E USH 18 WB(BEGIN 9.59 1.2 5.85 0.72 110

C|057N|009904|018380 Int/Urb; 4-leg signalized OZAUKEE SR057N CTH W 6.48 2.93 5.83 1 111


C|041N|015661|002530 Int/Urb; 4-leg signalized MILWAUKEE US041N N 55TH ST 6.48 2.87 5.81 0.99 113


C|060E|006359|121570 Int/Urb; 3-leg signalized WASHINGTON SR060E LONE OAK LA 6.92 2.56 5.72 0.92 115

C|018E|018651|158340 Int/Urb; 4-leg signalized MILWAUKEE US018E N WATER ST 7.11 1.82 5.71 0.88 116

C|020E|002075|038150 Int/Urb; 4-leg signalized RACINE SR020E STH 31 SB 6.27 3.04 5.7 0.98 117

C|057N|006032|003430 Int/Urb; 4-leg signalized MILWAUKEE SR057N W LOCUST ST 7.32 1.59 5.65 0.84 118

C|190E|010234|004730 Int/Urb; 3-leg signalized WAUKESHA SR190E BUSINESS ENT 6.02 4.05 5.64 1.02 119

C|059E|006244|095260 Int/Urb; 4-leg signalized WAUKESHA SR059E CTH D 6.06 3.33 5.62 0.98 120

C|050W|011037|001050 Int/Urb; 4-leg signalized KENOSHA SR050W 60TH AVE 6.06 3.17 5.57 0.97 121

C|018E|019125|142630 Int/Urb; 4-leg signalized WAUKESHA US018E MORELAND BLVD E 6.27 2.63 5.55 0.93 122

C|038N|004219|002600 Int/Urb; 3-leg signalized RACINE SR038N RAPIDS DR 6.02 3.64 5.52 0.97 123

C|241N|004400|009340 Int/Urb; 4-leg signalized MILWAUKEE SR241N W HOWARD AVE 6.06 2.98 5.51 0.94 124

C|011E|013078|148750 Int/Urb; 4-leg minor-rd STOP RACINE SR011E HAMILTON AVE 6.85 0.83 5.5 0.89 125

C|158E|009770|005430 Int/Urb; 4-leg minor-rd STOP KENOSHA SR158E 40TH AVE 6.64 0.96 5.5 0.91 126

C|059E|010917|107840 Int/Urb; 3-leg signalized MILWAUKEE SR059E STH 341 NB 7.36 1.87 5.48 0.8 127

C|032N|003273|015760 Int/Urb; 4-leg signalized RACINE SR032N 14TH ST 7.53 1.33 5.48 0.77 128

C|057N|016521|006520 Int/Urb; 3-leg signalized MILWAUKEE SR057N LINCOLN PARK DR 7.59 1.71 5.46 0.78 129

67

C|020E|002077|038510 Int/Urb; 4-leg signalized RACINE SR020E PERRY AVE 6.27 2.44 5.46 0.9 130

C|059W|011166|010980 Int/Urb; 4-leg signalized WAUKESHA SR059W CTH Y 6.06 2.84 5.46 0.93 131

C|038N|004230|014740 Int/Urb; 4-leg signalized MILWAUKEE SR038N STH 100 NB 6.06 2.83 5.45 0.93 132

C|164N|009857|010300 Int/Urb; 4-leg signalized WAUKESHA SR164N CTH ES 6.27 2.42 5.45 0.9 133

C|181N|017219|010320 Int/Urb; 4-leg signalized MILWAUKEE SR181N W BRADLEY RD 6.27 2.41 5.45 0.9 134

C|190E|010262|016340 Int/Urb; 4-leg signalized MILWAUKEE SR190E N TEUTONIA AV 6.06 2.8 5.45 0.92 135

C|038N|004240|021770 Int/Urb; 4-leg signalized MILWAUKEE SR038N HOWARD AVE 6.27 2.4 5.44 0.89 136

C|190E|010241|008790 Int/Urb; 4-leg signalized WAUKESHA SR190E LILLY RD 5.85 3.3 5.43 0.95 137

C|020E|002079|039180 Int/Urb; 4-leg signalized RACINE SR020E LATHROP AVE 6.48 2.08 5.43 0.86 138

C|018W|019126|012090 Int/Urb; 3-leg signalized WAUKESHA US018W MAIN ST 6.47 2.56 5.39 0.87 139

C|175N|010034|005950 Int/Urb; 4-leg signalized WASHINGTON SR175N CTH Q 6.48 2.02 5.39 0.85 140

C|190E|016638|018210 Int/Urb; 4-leg signalized MILWAUKEE SR190E N OAKLAND AVE 6.48 2.01 5.38 0.85 141

C|145N|009499|004740 Int/Urb; 3-leg signalized MILWAUKEE SR145N N 51ST ST 6.25 2.84 5.38 0.89 142

C|032N|018118|020900 Int/Urb; 4-leg signalized RACINE SR032N CTH G 6.27 2.22 5.35 0.86 143

C|050W|017652|004780 Int/Urb; 3-leg signalized KENOSHA SR050W ON RAMP FROM I9 5.8 3.61 5.34 0.94 144

C|031S|010761|004800 Int/Urb; 3-leg signalized RACINE SR031S NEWMAN RD 5.8 3.61 5.34 0.94 145

C|041N|017927|006510 Int/Urb; 4-leg signalized MILWAUKEE US041N CTH F 6.27 2.18 5.33 0.86 146

C|018E|001934|150650 Int/Urb; 4-leg signalized MILWAUKEE US018E STH 100 SB 6.06 2.5 5.32 0.88 147

C|083N|012177|035220 Int/Urb; 3-leg signalized WAUKESHA SR083N ON RAMP FRM IH 6.69 2.19 5.31 0.82 148

C|050W|019865|004600 Int/Urb; 4-leg signalized KENOSHA SR050W 118TH AVE 5.85 2.85 5.29 0.9 149

C|050W|019864|002790 Int/Urb; 4-leg signalized KENOSHA SR050W CTH H 5.85 2.85 5.29 0.9 150

C|059W|016885|005400 Int/Urb; 3-leg signalized WAUKESHA SR059W CTH O 6.69 2.16 5.29 0.81 151

C|059E|016593|104880 Int/Urb; 4-leg signalized MILWAUKEE SR059E S 92ND ST 6.06 2.39 5.28 0.87 152

C|241N|004391|005360 Int/Urb; 4-leg signalized MILWAUKEE SR241N W RAWSON AVE 5.85 2.69 5.23 0.88 153

C|036N|012450|011200 Int/Urb; 4-leg signalized RACINE SR036N CTH W 6.27 2 5.22 0.82 154

C|190E|010232|001390 Int/Urb; 3-leg signalized WAUKESHA SR190E MEADOW CREEK DR 5.8 3.25 5.21 0.9 155

C|100N|008686|020310 Int/Urb; 4-leg signalized MILWAUKEE SR100N CTH EE 6.27 1.97 5.2 0.82 156

68

C|032N|003286|019850 Int/Urb; 4-leg signalized RACINE SR032N 3 MILE RD 6.06 2.22 5.19 0.84 157

C|059E|006248|103890 Int/Urb; 4-leg signalized MILWAUKEE SR059E STH 100 NB 5.64 2.93 5.15 0.88 158

C|024E|002600|007850 Int/Urb; 4-leg signalized MILWAUKEE SR024E S 27TH ST (SB) 6.06 2.13 5.14 0.82 159

C|060E|006354|120290 Int/Urb; 4-leg signalized WASHINGTON SR060E MAIN ST 5.85 2.45 5.14 0.85 160

C|100S|016515|015480 Int/Urb; 3-leg signalized MILWAUKEE SR100S OFF RAMP TO IH 5.35 4.09 5.11 0.92 161

C|158E|009764|002470 Int/Urb; 4-leg signalized KENOSHA SR158E CTH H 5.85 2.38 5.11 0.84 162

C|059E|006244|095590 Int/Urb; 4-leg signalized WAUKESHA SR059E PEARL ST 5.44 3.33 5.09 0.89 163

C|145N|009493|003250 Int/Urb; 3-leg minor-rd STOP MILWAUKEE SR145N STH 145 SB (BEG 7.37 0.34 5.09 0.72 164

C|794E|012930|008820 Int/Urb; 3-leg minor-rd STOP MILWAUKEE I794E ENTRANCE SUPER 7.58 0.31 5.08 0.7 165

C|050E|017649|037570 Int/Urb; 3-leg minor-rd STOP KENOSHA SR050E ON RAMP FROM IH 7.16 0.37 5.08 0.74 166

C|045N|017930|033480 Int/Urb; 3-leg minor-rd STOP MILWAUKEE US045N W COBB AVE 6.95 0.4 5.05 0.75 167

C|100N|016921|021200 Int/Urb; 4-leg signalized MILWAUKEE SR100N 115 ST 6.06 1.97 5.04 0.79 168

C|031S|010744|014840 Int/Urb; 4-leg signalized KENOSHA SR031S CTH K 5.44 3.14 5.04 0.87 169

C|045N|004739|059180 Int/Rur; 4-leg signalized WASHINGTON US045N CTH H 5.89 2.11 5.01 0.81 170

Table A.4 — 5% Screening of SE Region Segments


Location

Site End

Location

Average

Observed

Accidents for

Entire Site*


Rank Average

Observed

Accidents*

Predicted

Accident

Frequency*

Expected

Accident

Frequency*

Variance** Start

Location

End

Location

S014169 Seg/Urb; Fwy in intchng area (6 ln) MILWAUKEE I094E 215.82 216.31 125.62 281.52 36.34 259.97 49.82 216.02 216.12 1

S014532 Seg/Urb; Fwy (6 ln) WAUKESHA I094E 209.58 210.63 48.39 212.79 20.09 177.38 31.44 209.68 209.78 2

S014892 Seg/Urb; Fwy (8+ ln) MILWAUKEE I094E 219.38 219.71 82.12 169.97 42.08 159.99 23.65 219.48 219.58 3

S014177 Seg/Urb; Fwy (6 ln) MILWAUKEE I094W 36.94 37.65 63.61 167.2 23.11 143.61 26.08 36.94 37.04 4

S016264 Seg/Urb; Fwy (6 ln) MILWAUKEE I043N 66.67 67.76 37.05 171.54 18.54 141.53 24.7 67.37 67.47 5

S014891 Seg/Urb; Fwy (6 ln) MILWAUKEE I094E 218.96 219.38 87.37 162.85 21.89 138.71 24.96 218.96 219.06 6

69

S016408 Seg/Urb; Fwy (6 ln) MILWAUKEE I043S 122.11 123.11 62.1 158.51 18.54 131.06 22.88 122.41 122.51 7


S014179 Seg/Urb; Fwy in intchng area (4 ln) MILWAUKEE I094W 37.85 38.35 82.62 128.43 39.47 122.85 24.65 38.25 38.35 9




S014916 Seg/Urb; Fwy (8+ ln) MILWAUKEE I094E 220.02 220.45 85.4 120.26 38.14 113.24 16.61 220.22 220.32 13










S016715 Seg/Urb; Fwy in intchng area (6 ln) MILWAUKEE US045S 53.39 53.62 68.51 96.64 40.75 92.22 17.84 53.49 53.59 23



S016222 Seg/Urb; Fwy (6 ln) MILWAUKEE I043N 65.09 65.59 45.16 104.23 21.04 89.51 16 65.09 65.19 26

S013827 Seg/Urb; Fwy (6 ln) MILWAUKEE US045S 49.41 50.41 30.62 102.05 21.13 87.78 15.7 49.41 49.51 27

S014989 Seg/Urb; Fwy in intchng area (8+ ln) MILWAUKEE I094W 34.74 35.17 58.14 93.33 29.91 87.19 13.13 34.94 35.04 28

S017170 Seg/Urb; Fwy (6 ln) MILWAUKEE US045N 38.62 39.62 28.45 99.88 21.13 86 15.38 38.62 38.72 29




70


S004209 Seg/Urb; 2-lane arterial RACINE SR038N 0.79 0.84 92.75 92.75 6.35 81.85 14.42 0.79 0.84 34

S013190 Seg/Urb; Fwy (4 ln) MILWAUKEE I894E 0 0.14 104.09 137.28 2.98 81.26 10 0.04 0.14 35

S015675 Seg/Urb; Fwy (6 ln) MILWAUKEE US045N 37.53 38.62 31.67 91.2 21.34 78.98 14.15 37.63 37.73 36


S013144 Seg/Urb; Fwy in intchng area (6 ln) MILWAUKEE I894W 2 2.99 42.87 81.93 40.75 78.67 15.22 2.4 2.5 38

S014522 Seg/Urb; Fwy (6 ln) WAUKESHA I094W 41.46 42.51 25.64 89.03 21.77 77.45 13.92 41.56 41.66 39


S015672 Seg/Urb; Fwy in intchng area (6 ln) MILWAUKEE US045N 34.79 35.4 35.13 75.63 40.75 72.87 14.1 35.19 35.29 41






S013157 Seg/Urb; Fwy (6 ln) MILWAUKEE I043N 73.95 74.71 23.14 76 21.17 66.34 11.87 73.95 74.05 47

S016268 Seg/Urb; Fwy (8+ ln) MILWAUKEE I043S 123.68 123.69 112.24 112.24 29 66.34 4.77 123.68 123.69 48

S016136 Seg/Urb; Fwy (6 ln) MILWAUKEE I043S 116.76 117.5 36.97 76 20.78 66.13 11.79 116.76 116.86 49

S016227 Seg/Urb; Fwy (6 ln) MILWAUKEE I043S 127.44 128.3 36.61 76 20.4 65.91 11.71 127.84 127.94 50

S014894 Seg/Urb; Fwy in intchng area (8+ ln) MILWAUKEE I094E 219.79 220.02 42.75 68.33 29.91 64.61 9.73 219.92 220.02 51

S016234 Seg/Urb; Fwy in intchng area (6 ln) MILWAUKEE I043S 124.21 124.71 33.19 67.23 34.15 64.15 12.22 124.21 124.31 52


S016407 Seg/Urb; Fwy (8+ ln) MILWAUKEE I043N 66.39 66.67 30.92 67.35 31.87 63.78 9.2 66.57 66.67 54





71


S013794 Seg/Urb; Fwy (6 ln) MILWAUKEE I894E 1.94 2.68 27.29 67.31 22 59.59 10.73 2.14 2.24 60


S010782 Seg/Urb; One-way arterial MILWAUKEE SR032S 26.23 26.64 42.13 68.24 7.92 58.4 10.42 26.23 26.33 62


S004410 Seg/Urb; 2-lane arterial MILWAUKEE US041N 2.8 3.03 36.82 60.49 10.13 58.31 11.25 2.93 3.03 64


S001919 Seg/Urb; One-way arterial WAUKESHA US018E 140.48 140.69 32.5 61.84 11.3 55.76 10.46 140.48 140.58 66

S006251 Seg/Urb; 2-lane arterial MILWAUKEE SR059E 106.25 106.78 31.96 58.47 7.85 55.68 10.61 106.55 106.65 67

S020717 Seg/Urb; One-way arterial MILWAUKEE US018E 157.1 157.16 67.53 67.53 9.7 55.4 9.33 157.1 157.16 68



S014176 Seg/Urb; Fwy (6 ln) MILWAUKEE I094W 36.57 36.94 36.39 60.8 23.69 54.85 10 36.84 36.94 71



S016144 Seg/Urb; Fwy (6 ln) MILWAUKEE I043N 75.98 76.97 24.78 60.8 21.58 54 9.69 75.98 76.08 74


S012801 Seg/Urb; One-way arterial WAUKESHA US018W 14.12 14.33 34.53 59.71 10.94 53.67 10.03 14.12 14.22 76


S005286 Seg/Urb; 2-lane arterial WALWORTH SR050E 12.13 12.22 56.01 56.01 8.06 53.16 10.08 12.13 12.22 78

S002079 Seg/Urb; 2-lane arterial RACINE SR020E 39.17 39.67 33.47 56.46 6.07 52.92 9.92 39.57 39.67 79



S018134 Seg/Urb; 2-lane arterial RACINE SR036N 8.72 8.94 33.91 52.42 8.89 50.29 9.64 8.72 8.82 82


S013142 Seg/Urb; Fwy (6 ln) MILWAUKEE I894W 1.32 2 37.04 56.46 19.44 49.47 8.71 1.52 1.62 84

72




S020730 Seg/Urb; One-way arterial MILWAUKEE US018E 157.81 157.88 54.84 54.84 12.66 48.57 8.82 157.81 157.88 88

S015674 Seg/Urb; Fwy (6 ln) MILWAUKEE US045N 36.17 37.53 28.58 52.11 23.01 47.33 8.59 37.37 37.47 89



S016140 Seg/Urb; Fwy (8+ ln) MILWAUKEE I043N 71 71.22 40.09 48.1 35.9 47 6.86 71 71.1 92

S016921 Seg/Urb; 2-lane arterial MILWAUKEE SR100N 21.18 21.22 65.53 65.53 2.71 46.89 6.65 21.18 21.22 93

73

Table A.5 — 5% Screening of NE Region Intersections



Rank Average

Observed

Accidents*

Predicted

Accident

Frequency*

Expected

Accident

Frequency*

Variance**

C|021E|002203|120220 Int/Urb; 3-leg signalized WINNEBAGO SR021E ON RAMP FROM ST 19.19 3.24 15.51 2.66 1

C|015E|013411|014670 Int/Urb; 4-leg signalized OUTAGAMIE SR015E CASALOMA DR 15.05 3.01 12.9 2.22 2

C|023E|017519|157790 Int/Urb; 4-leg signalized FOND DU LAC SR023E PIONEER RD 13.59 2.81 11.55 1.96 3

C|023E|002545|159430 Int/Urb; 4-leg signalized FOND DU LAC SR023E USH 151 NB 12.12 2.63 10.23 1.71 4

C|015E|013409|013220 Int/Urb; 3-leg signalized OUTAGAMIE SR015E CTH CB 12.49 2.28 9.44 1.48 5

C|047N|004973|006170 Int/Urb; 3-leg signalized OUTAGAMIE SR047N STH 47S (BEGIN 12.94 1.87 9.17 1.35 6

C|045N|004787|105150 Int/Urb; 3-leg minor-rd STOP WINNEBAGO US045N SARATOGA AVE 12.85 0.29 8.31 1.12 7

C|096E|000561|019900 Int/Urb; 3-leg signalized OUTAGAMIE SR096E OFF RAMP TO USH 9.82 2.95 8.12 1.36 8

C|045N|018792|105840 Int/Urb; 4-leg minor-rd STOP WINNEBAGO US045N WISCONSIN ST 9.97 0.8 7.84 1.25 9

C|032N|019770|143020 Int/Urb; 4-leg signalized BROWN SR032N S TAYLOR ST 8.99 2.81 7.82 1.33 10

C|125W|017670|002250 Int/Urb; 3-leg minor-rd STOP OUTAGAMIE SR125W WESTHILL BLVD 10.74 0.38 7.59 1.11 11

C|047N|004971|005180 Int/Urb; 4-leg signalized OUTAGAMIE SR047N STH 96 EB 8.78 2.46 7.46 1.23 12

C|032S|013405|008510 Int/Urb; 4-leg minor-rd STOP BROWN SR032S TAYLOR ST 8.93 1.01 7.4 1.24 13

C|021W|010667|000410 Int/Urb; 3-leg minor-rd STOP WINNEBAGO SR021W ON RAMP FROM ST 10.53 0.37 7.38 1.07 14

C|028E|003095|058190 Int/Urb; 4-leg signalized SHEBOYGAN SR028E INDIANA AVE 8.57 2.47 7.29 1.21 15

C|029E|003181|238680 Int/Urb; 3-leg signalized BROWN SR029E CARDINAL LA 7.81 4.05 7.08 1.27 16

C|125E|009073|000620 Int/Urb; 4-leg signalized OUTAGAMIE SR125E BLUEMOUND RD 7.94 2.99 7.05 1.21 17

C|023E|017530|158650 Int/Urb; 4-leg signalized FOND DU LAC SR023E HICKORY ST 7.94 2.78 6.96 1.18 18

C|023E|002543|157470 Int/Urb; 4-leg signalized FOND DU LAC SR023E CTH VVV 7.94 2.74 6.94 1.17 19

C|114E|011918|001390 Int/Urb; 3-leg minor-rd STOP WINNEBAGO SR114E CHURCH ST 10.74 0.28 6.88 0.91 20

C|029E|003181|239280 Int/Urb; 3-leg signalized BROWN SR029E CONNECTOR FROM 7.36 4.05 6.72 1.21 21

74

C|032N|019770|142240 Int/Urb; 4-leg signalized BROWN SR032N MILITARY AVE 7.53 2.81 6.64 1.13 22

C|028E|018001|056340 Int/Urb; 3-leg minor-rd STOP SHEBOYGAN SR028E CTH OK 10.11 0.3 6.64 0.9 23

C|041N|004452|180380 Int/Urb; 4-leg signalized MARINETTE US041N ROOSEVELT RD 7.73 2.34 6.56 1.07 24

C|125E|020309|001110 Int/Urb; 4-leg signalized OUTAGAMIE SR125E LYNNDALE DR 7.11 2.88 6.33 1.08 25

C|023W|017520|019060 Int/Urb; 4-leg signalized FOND DU LAC SR023W PIONEER RD 7.11 2.81 6.3 1.07 26

C|028E|017996|055290 Int/Urb; 3-leg signalized SHEBOYGAN SR028E CTH TA 8.7 1.71 6.17 0.88 27

C|141N|011818|003610 Int/Urb; 3-leg signalized BROWN US141N VERLIN RD 7.81 2 5.91 0.89 28

C|125W|017670|002000 Int/Urb; 4-leg signalized OUTAGAMIE SR125W BLUEMOUND DR 6.27 3.02 5.69 0.98 29

C|021E|002203|120110 Int/Urb; 3-leg signalized WINNEBAGO SR021E ABRAHAM LN 5.8 3.24 5.21 0.89 30

C|045N|004770|085850 Int/Urb; 4-leg signalized FOND DU LAC US045N JOHNSON ST 6.06 2.1 5.12 0.82 31

C|096E|000557|017910 Int/Urb; 4-leg signalized OUTAGAMIE SR096E CTH CB 6.06 1.98 5.05 0.79 32

C|047N|004964|004140 Int/Urb; 3-leg signalized OUTAGAMIE SR047N W 6TH ST 7.36 1.49 5.05 0.68 33

C|047N|004959|001990 Int/Urb; 4-leg signalized WINNEBAGO SR047N CTH AP 5.64 2.62 5.04 0.84 34

C|114W|012252|000800 Int/Urb; 4-leg minor-rd STOP WINNEBAGO SR114W GREEN BAY RD 6.02 0.99 5.03 0.84 35

Table A.6 — 5% Screening of NE Region Segments


Location

Site End

Location

Average

Observed

Accidents for

Entire Site*


Rank Average

Observed

Accidents*

Predicted

Accident

Frequency*

Expected

Accident

Frequency*

Variance** Start

Location

End

Location

S002545 Seg/Urb; 2-lane arterial FOND DU LAC SR023E 159.43 159.53 96.78 96.78 9.66 92.84 17.87 159.43 159.53 1

S014283 Seg/Urb; Fwy (4 ln) WINNEBAGO US041N 80.77 81.3 31.48 97.15 8.23 78.86 13.23 80.77 80.87 2

S015030 Seg/Urb; Fwy (4 ln) BROWN US041N 128.35 128.77 27.15 88.7 9.11 73.59 12.59 128.67 128.77 3

S014693 Seg/Urb; Fwy (4 ln) WINNEBAGO US010W 13.61 14.47 19.89 95.04 5.7 70.72 10.87 14.01 14.11 4


75

S014282 Seg/Urb; Fwy in intchng area (4 ln) WINNEBAGO US041N 79.27 80.77 9.42 57.79 13.03 50.24 8.94 80.67 80.77 6

S014704 Seg/Urb; Fwy (8+ ln) WINNEBAGO US041S 68.27 68.79 18.5 49.71 20.75 45.47 6.22 68.69 68.79 7

S014305 Seg/Urb; Fwy in intchng area (4 ln) WINNEBAGO US041S 77.05 77.48 18.92 53.51 10.92 45.21 7.79 77.05 77.15 8



S014553 Seg/Urb; Fwy (4 ln) BROWN SR172E 8.96 9.95 10.24 48.58 6.56 38.26 6.1 9.85 9.95 11





S004692 Seg/Urb; 2-lane arterial WINNEBAGO SR044N 61.6 61.66 36.97 36.97 8.28 34.54 6.38 61.6 61.66 16

S014710 Seg/Urb; Fwy (6 ln) WINNEBAGO US041S 65.45 66.66 11.31 41.26 13.64 34.38 5.61 65.45 65.55 17





S015075 Seg/Urb; Fwy (4 ln) BROWN US041S 33.01 33.95 10.56 38.02 9.34 32.68 5.62 33.85 33.95 22




S010452 Seg/Urb; One-way arterial MANITOWOC US010W 0.36 0.42 35.54 35.54 10.13 30.39 5.17 0.36 0.42 26


S000612 Seg/Urb; One-way arterial MANITOWOC US010E 285.89 285.95 35.54 35.54 9.77 30.17 5.09 285.89 285.95 28


S014641 Seg/Urb; Fwy (4 ln) OUTAGAMIE SR441N 3.58 4.36 7.31 40.13 5.02 29.66 4.4 4.26 4.36 30


76


S011662 Seg/Urb; Fwy (4 ln) OUTAGAMIE SR441S 1.01 1.81 8.18 38.02 5.46 28.88 4.39 1.01 1.11 33

S008530 Seg/Urb; 2-lane arterial OUTAGAMIE SR096E 22.68 22.92 17.64 30.24 6.22 28.6 5.37 22.82 22.92 34



S004693 Seg/Urb; 2-lane arterial WINNEBAGO SR044N 61.66 61.78 23.52 28.23 8.28 27.18 5.19 61.68 61.78 37

S004773 Seg/Urb; 2-lane arterial FOND DU LAC US045N 86.88 88.18 3.41 30.24 3.41 27.07 4.81 86.88 86.98 38




S014721 Seg/Urb; Fwy (4 ln) OUTAGAMIE US041N 100.88 101.78 6.1 31.68 7.15 26.04 4.24 101.68 101.78 42







S014716 Seg/Urb; Fwy (6 ln) OUTAGAMIE US041S 62.53 63.42 7.81 30.4 10.97 24.73 3.8 63.32 63.42 49

S014730 Seg/Urb; Fwy (4 ln) OUTAGAMIE US041S 58.4 59.38 6.68 29.57 7.25 24.49 4 59.28 59.38 50


S012237 Seg/Urb; 2-lane arterial WINNEBAGO US045N 103.97 104.03 26.88 26.88 5.2 24.11 4.24 103.97 104.03 52






77



S015684 Seg/Urb; Fwy in intchng area (4 ln) WINNEBAGO US010E 239.76 239.84 42.81 42.81 3.13 22.45 2.34 239.76 239.84 60




S014304 Seg/Rur; Fwy (4 ln) WINNEBAGO US041S 75.49 77.05 7.38 60.82 5.43 21.95 1.42 76.95 77.05 64

S015023 Seg/Urb; Fwy in intchng area (4 ln) BROWN US041N 124.95 125.24 11.07 23.55 13.15 21.81 3.89 124.95 125.05 65

S014691 Seg/Urb; Fwy (4 ln) WINNEBAGO US010E 241.09 241.96 10.92 27.46 5.7 21.53 3.31 241.49 241.59 66


S013403 Seg/Urb; One-way arterial BROWN SR032S 8.31 8.44 16.4 21.33 22.12 21.38 4.26 8.31 8.41 68



S019806 Seg/Urb; Fwy (4 ln) FOND DU LAC US041N 57.34 58.64 9.45 29.57 4.24 21.09 2.96 58.44 58.54 71

S014625 Seg/Urb; Fwy (4 ln) OUTAGAMIE SR441N 6.92 7.15 17.45 31.68 3.5 21.02 2.76 7.02 7.12 72

S009979 Seg/Urb; 2-lane arterial BROWN SR172E 1.4 2.34 4.5 22.18 5.64 20.94 3.9 1.4 1.5 73

S012380 Seg/Rur; Fwy (4 ln) WINNEBAGO US041N 85.73 87.32 8.88 56.48 5.43 20.65 1.34 85.73 85.83 74






S015686 Seg/Urb; Fwy (4 ln) WINNEBAGO US010E 240.03 240.74 4.46 23.23 7.86 19.95 3.31 240.03 240.13 80

S014635 Seg/Urb; Fwy (4 ln) OUTAGAMIE SR441N 5.55 6.35 5.02 25.34 5.46 19.76 3 6.25 6.35 81


S020556 Seg/Urb; One-way arterial BROWN SR032S 15.69 15.84 17.06 21.33 9.54 19.68 3.61 15.69 15.79 83

78

S014456 Seg/Urb; Fwy (4 ln) BROWN I043N 190.89 191.8 5.11 27.46 4.24 19.68 2.76 191.7 191.8 84





S012245 Seg/Urb; One-way arterial WINNEBAGO US045S 27.2 27.27 21.33 21.33 9.53 19.11 3.31 27.2 27.27 89


S004767 Seg/Urb; One-way arterial FOND DU LAC US045N 85.06 85.42 14.22 21.33 6.96 18.71 3.27 85.16 85.26 91









S014649 Seg/Urb; Fwy (4 ln) OUTAGAMIE SR441S 3.78 4.01 11.94 23.23 4.53 17.25 2.48 3.91 4.01 100


S014465 Seg/Urb; Fwy (4 ln) BROWN I043S 7.85 8.85 4.22 23.23 4.35 17.02 2.41 8.75 8.85 102

S008946 Seg/Urb; 2-lane arterial WINNEBAGO SR114E 3.36 3.51 13.44 18.15 4.63 16.93 3.11 3.41 3.51 103







79





S014732 Seg/Urb; Fwy (4 ln) OUTAGAMIE US041S 56.31 57.38 5.72 19.01 6.94 16.17 2.61 57.28 57.38 114




S014446 Seg/Urb; Fwy (4 ln) BROWN I043S 8.85 10.33 4.99 21.12 4.71 16 2.33 10.23 10.33 118

S019850 Seg/Urb; One-way arterial WINNEBAGO SR021E 121.46 121.55 16.59 16.59 11.08 15.85 2.93 121.46 121.55 119

S014647 Seg/Urb; Fwy (4 ln) CALUMET SR441N 1.91 3.35 4.4 21.12 4.53 15.81 2.27 3.25 3.35 120


S014711 Seg/Urb; 2-lane arterial OUTAGAMIE SR125E 0 0.36 8.4 16.13 7.23 15.6 2.96 0.1 0.2 122

S008531 Seg/Urb; 2-lane arterial OUTAGAMIE SR096E 22.92 23.17 10.48 16.13 6.56 15.51 2.92 23.07 23.17 123






80

Table A.7 — 5% Screening of NC Region Intersections



Rank Average

Observed

Accidents*

Predicted

Accident

Frequency*

Expected

Accident

Frequency*

Variance**

C|051N|005413|161100 Int/Rur; 3-leg signalized ONEIDA US051N STH 70 EB (S J 15.23 2.76 12.55 2.46 1

C|B051N|020180|007940 Int/Urb; 3-leg signalized MARATHON BRB051N IMPERIAL AVE 15.17 2.01 10.89 1.64 2

C|B051N|010364|014120 Int/Urb; 3-leg signalized MARATHON BRB051N CTH N 7.14 3.44 6.33 1.1 3

C|B051N|010345|005770 Int/Urb; 4-leg signalized PORTAGE BRB051N 4TH AVE 6.69 2.33 5.73 0.94 4

C|052W|012065|002660 Int/Urb; 4-leg minor-rd STOP MARATHON SR052W 17TH AVE S (SB 6.44 1.02 5.4 0.91 5

C|010E|017229|176200 Int/Urb; 3-leg signalized PORTAGE US010E MICHIGAN AVE 9.15 1.08 5.33 0.63 6

C|010E|000534|179020 Int/Urb; 4-leg signalized PORTAGE US010E BRILOWSKI RD 6.06 2.33 5.25 0.86 7

Table A.8 — 5% Screening of NC Region Segments


Location

Site End

Location

Average

Observed

Accidents for

Entire Site*


Rank Average

Observed

Accidents*

Predicted

Accident

Frequency*

Expected

Accident

Frequency*

Variance** Start

Location

End

Location

S019569 Seg/Urb; Fwy in intchng area (6 ln) MARATHON US051N 88.76 89.38 15.25 48.32 10.93 39.25 6.24 89.28 89.38 1

S019548 Seg/Urb; One-way arterial MARATHON BRB051N 15.1 15.77 10.19 34.12 9.06 30.47 5.55 15.67 15.77 2

S005477 Seg/Urb; One-way arterial MARATHON SR052E 2.05 2.1 34.12 34.12 13.64 30.34 5.27 2.05 2.1 3

S020190 Seg/Urb; Fwy (4 ln) MARATHON US051N 88.48 88.76 14.33 35.9 6.88 29.04 4.68 88.66 88.76 4



S015133 Seg/Urb; Fwy (4 ln) MARATHON US051S 52.8 54.1 8.29 33.79 6.01 26.51 4.13 53 53.1 7


81

S011989 Seg/Urb; 2-lane arterial WAUPACA US045N 132.09 133.4 4.16 26.21 4.98 24.42 4.51 133.3 133.4 9



S013703 Seg/Urb; Fwy (4 ln) MARATHON I039N 179.35 179.44 30.51 30.51 4.12 20.88 2.8 179.35 179.44 12

S010345 Seg/Urb; Fwy (4 ln) PORTAGE BRB051N 5.59 5.81 20.16 29.57 4.06 20.78 2.88 5.69 5.79 13

S005484 Seg/Urb; 2-lane arterial MARATHON SR052E 3.22 3.86 10.71 22.18 4.95 20.72 3.82 3.32 3.42 14


S019572 Seg/Urb; Fwy in intchng area (6 ln) MARATHON US051S 55.75 56.37 7.45 23.11 10.93 20.15 3.21 56.27 56.37 16

S020195 Seg/Urb; Fwy in intchng area (4 ln) MARATHON I039S 2.8 2.91 23.35 25.69 6.11 19.78 2.96 2.81 2.91 17

S005197 Seg/Urb; 2-lane arterial GREEN LAKE SR049N 34.69 34.91 10.08 22.18 2.74 19.39 3.35 34.81 34.91 18

S002293 Seg/Urb; 2-lane arterial WAUPACA SR022N 76.9 76.97 23.04 23.04 2.84 19.26 3.16 76.9 76.97 19

S013597 Seg/Urb; Fwy (4 ln) MARATHON I039S 8.76 9.75 4.05 27.46 3.04 17.38 2.16 8.76 8.86 20





S019567 Seg/Urb; One-way arterial MARATHON BRB051S 2.06 2.57 8.78 17.06 9.53 16.01 2.94 2.16 2.26 25


S010351 Seg/Urb; 2-lane arterial MARATHON BRB051N 9.54 10.22 4.74 16.13 8.05 15.7 2.99 9.84 9.94 27



S000529 Seg/Urb; One-way arterial PORTAGE US010E 176.04 176.13 16.59 16.59 9.68 15.55 2.82 176.04 176.13 30


S020622 Seg/Urb; 2-lane arterial LINCOLN SR064E 146.27 146.34 17.28 17.28 3.54 15.14 2.58 146.27 146.34 32

S015132 Seg/Urb; Fwy (4 ln) MARATHON US051S 52.26 52.8 7.82 19.01 5.23 15.02 2.25 52.26 52.36 33

S020625 Seg/Urb; 2-lane arterial LINCOLN SR064E 146.77 147 8.77 16.13 3.5 14.67 2.61 146.87 146.97 34

S019566 Seg/Urb; One-way arterial MARATHON BRB051S 1.74 2.06 11.33 14.93 9.59 14.19 2.61 1.96 2.06 35

82

S013672 Seg/Urb; Fwy (4 ln) PORTAGE I039N 152.46 153.08 8.18 21.12 3.33 14.17 1.82 152.46 152.56 36






S010022 Seg/Urb; 2-lane arterial WOOD SR173N 34.96 35.44 6.3 14.11 5.77 13.5 2.52 35.26 35.36 42



S002514 Seg/Rur; 2-lane GREEN LAKE SR023E 134.52 135.53 12.88 28.02 2.79 13.16 1.08 134.62 134.72 45


S000255 Seg/Urb; 2-lane arterial ONEIDA US008E 164.42 165.72 4.19 14.11 2.97 12.63 2.21 164.42 164.52 47

S013233 Seg/Rur; 2-lane WAUSHARA SR021E 88.89 90.14 7.05 30.02 2.36 12.63 0.94 88.99 89.09 48





S012914 Seg/Urb; One-way arterial MARATHON SR052W 1.17 1.4 9.27 12.8 8.45 12.12 2.19 1.3 1.4 53


S018560 Seg/Urb; 2-lane arterial SHAWANO SR047N 39.69 39.77 12.6 12.6 4.51 11.69 2.09 39.69 39.77 55


S013619 Seg/Urb; Fwy (4 ln) PORTAGE I039S 29.57 29.86 7.28 16.9 3.33 11.6 1.49 29.76 29.86 57



S019005 Seg/Urb; 2-lane arterial WOOD SR054E 97.23 97.61 6.37 12.1 5 11.5 2.12 97.51 97.61 60

S007755 Seg/Urb; 2-lane arterial IRON SR077E 120.72 120.8 12.6 12.6 3.93 11.5 2.02 120.72 120.8 61

S005779 Seg/Urb; 2-lane arterial WAUPACA SR054E 146.55 147.33 3.88 12.1 4.98 11.5 2.12 146.75 146.85 62

83

S015104 Seg/Urb; Fwy (4 ln) LINCOLN US051N 107.35 108.78 7.38 19.01 2.44 11.29 1.27 107.45 107.55 63

S018559 Seg/Urb; 2-lane arterial SHAWANO SR022N 122.68 122.81 12.41 12.1 4 11.26 2.04 122.71 122.81 64

S008588 Seg/Urb; 2-lane arterial MARATHON SR097N 2.25 2.85 4.03 12.1 3.88 11.23 2.03 2.55 2.65 65

S012640 Seg/Rur; 2-lane ONEIDA US051N 159.63 159.67 35.03 35.03 3.32 11.22 0.56 159.63 159.67 66








S015873 Seg/Urb; 2-lane arterial PORTAGE SR066E 4.09 5.01 6.14 12.1 2.7 10.73 1.85 4.19 4.29 74


S019112 Seg/Urb; One-way arterial MARATHON SR052E 1.28 1.49 7.11 10.66 11.02 10.71 2 1.38 1.48 76


S013696 Seg/Urb; Fwy (4 ln) MARATHON I039N 175 175.38 7.23 14.78 3.58 10.6 1.4 175.28 175.38 77








S004804 Seg/Rur; 2-lane WAUPACA US045N 143.39 144.5 4.51 22.02 2.62 10.3 0.82 143.59 143.69 86



84


S010328 Seg/Urb; 2-lane arterial PORTAGE BRB051N 0.14 0.58 5.04 10.08 6.42 9.84 1.85 0.48 0.58 90



S019002 Seg/Urb; 2-lane arterial WOOD SR054E 95.75 97.12 2.94 10.08 5.32 9.7 1.8 96.45 96.55 93






S011990 Seg/Urb; 2-lane arterial WAUPACA US045N 133.4 134.57 2.41 10.08 3.99 9.45 1.71 133.4 133.5 99

S016174 Seg/Rur; 2-lane SHAWANO US045N 159.68 160.68 6.4 28.02 1.67 9.43 0.56 159.68 159.78 100








S005008 Seg/Rur; 2-lane SHAWANO SR047N 31.81 32.79 3.68 22.02 2.13 9.03 0.63 31.81 31.91 108


S010418 Seg/Urb; One-way arterial PORTAGE US010W 78.83 79.1 4.74 8.53 10.37 8.77 1.63 79 79.1 110


S007754 Seg/Urb; 2-lane arterial IRON SR077E 120.66 120.72 10.08 10.08 3.05 8.67 1.4 120.66 120.72 112




85


S002307 Seg/Rur; 2-lane WAUPACA SR022N 87.38 88.48 4.18 20.01 2.2 8.52 0.6 87.38 87.48 117



S013620 Seg/Urb; Fwy (4 ln) PORTAGE I039S 29.86 30.07 7.04 12.67 2.79 8.39 1 29.86 29.96 120



S017230 Seg/Urb; One-way arterial PORTAGE US010E 176.47 176.55 8 8 9.14 8.2 1.44 176.47 176.55 123

S005777 Seg/Rur; 2-lane WAUPACA SR054E 144.52 145.25 7.4 16.01 2.77 8.19 0.67 144.62 144.72 124













S012442 Seg/Rur; 2-lane ADAMS SR013N 27.69 28.21 7.31 16.01 2.62 7.93 0.63 27.99 28.09 137

S004811 Seg/Rur; Fwy (4 ln) WAUPACA US045N 147.64 148.15 9.8 30.41 2.87 7.92 0.32 148.04 148.14 138


S015094 Seg/Rur; Fwy (4 ln) MARATHON US051N 96.45 97.77 4.61 36.93 2.4 7.85 0.27 97.67 97.77 140



86




S018626 Seg/Urb; 2-lane arterial ONEIDA SR047N 78.12 78.34 6.42 8.07 4.65 7.76 1.42 78.12 78.22 146




S018557 Seg/Urb; 2-lane arterial SHAWANO SR022N 122.29 122.54 4.03 8.07 4.26 7.7 1.4 122.29 122.39 150




S002305 Seg/Rur; 2-lane WAUPACA SR022N 86.06 87.15 3.49 18.01 2.12 7.62 0.53 87.05 87.15 154

S000518 Seg/Urb; 2-lane arterial PORTAGE US010E 173.39 174.41 3.36 8.07 3.76 7.6 1.37 173.49 173.59 155

S018997 Seg/Urb; 2-lane arterial WOOD SR054E 92.8 93.56 2.12 8.07 3.63 7.57 1.36 92.8 92.9 156







S010416 Seg/Urb; One-way arterial PORTAGE US010W 79.17 79.26 7.11 7.11 9.16 7.43 1.33 79.17 79.26 163



S012498 Seg/Urb; 2-lane arterial GREEN LAKE SR091E 0.5 0.75 4.03 8.07 3.04 7.41 1.3 0.6 0.7 166




87







S007292 Seg/Rur; 2-lane VILAS SR070E 148.85 150.48 3.81 20.01 1.68 7.11 0.42 148.85 148.95 176


88

Table A.9 — 5% Screening of NW Region Intersections



Rank Average

Observed

Accidents*

Predicted

Accident

Frequency*

Expected

Accident

Frequency*

Variance**

C|012E|000840|070820 Int/Urb; 3-leg signalized EAU CLAIRE US012E LONDON RD 13.61 3.44 11.37 1.98 1

C|012E|000832|068820 Int/Urb; 3-leg signalized EAU CLAIRE US012E UNIVERSITY DR 9.82 3.68 8.54 1.51 2

C|012E|012275|066200 Int/Urb; 3-leg signalized EAU CLAIRE US012E CTH E 8.25 3.37 7.17 1.24 3

C|012E|000802|042070 Int/Urb; 3-leg signalized DUNN US012E USH 12 7.81 2.26 6.14 0.96 4

C|012E|000837|070070 Int/Urb; 4-leg signalized EAU CLAIRE US012E RUDOLPH RD 6.27 3.03 5.7 0.98 5

C|012W|012274|104040 Int/Urb; 4-leg minor-rd STOP EAU CLAIRE US012W CAMERON ST 6.44 1.04 5.42 0.91 6

C|012W|010487|100200 Int/Urb; 4-leg signalized EAU CLAIRE US012W RUDOLPH RD 5.85 3.15 5.39 0.93 7

C|002E|000001|002240 Int/Urb; 4-leg signalized DOUGLAS US002E TOWER AVE 5.85 2.34 5.09 0.83 8

Table A.10 — 5% Screening of NW Region Segments


Location

Site End

Location

Average

Observed

Accidents for

Entire Site*


Rank Average

Observed

Accidents*

Predicted

Accident

Frequency*

Expected

Accident

Frequency*

Variance** Start

Location

End

Location

S014694 Seg/Urb; Fwy (6 ln) ST. CROIX I094W 248.78 249.4 15.76 62.97 13.05 50.12 8.08 248.78 248.88 1

S002650 Seg/Urb; 2-lane arterial DUNN SR025N 37.43 37.49 43.69 43.69 5.77 39.26 6.99 37.43 37.49 2

S014688 Seg/Urb; 2-lane arterial ST. CROIX SR035N 201.6 201.86 27.14 38.31 7.36 36.5 6.93 201.7 201.8 3

S013574 Seg/Urb; Fwy (4 ln) DOUGLAS I535N 0 1.21 11.87 48.58 4.05 33.22 4.6 0 0.1 4

S014593 Seg/Urb; Fwy (6 ln) ST. CROIX I094E 0.57 1.03 17.94 39.08 12.72 32.17 5.15 0.57 0.67 5



89


S000811 Seg/Urb; 2-lane arterial DUNN US012E 43.86 44.04 19.04 26.21 7.69 25.17 4.79 43.86 43.96 9


S016570 Seg/Urb; 2-lane arterial DOUGLAS SR035N 343.38 343.63 20.16 26.21 5.02 24.44 4.51 343.53 343.63 11

S014594 Seg/Urb; Fwy (6 ln) ST. CROIX I094E 1.03 1.73 9 28.23 13.08 24.34 3.93 1.03 1.13 12


S014692 Seg/Urb; Fwy (8+ ln) ST. CROIX I094W 248.36 248.78 10.69 25.66 14.23 23.37 3 248.36 248.46 14


S008454 Seg/Urb; Fwy (4 ln) EAU CLAIRE I094E 70.48 70.91 13.26 31.68 3.29 20.5 2.63 70.68 70.78 16

S016842 Seg/Urb; Fwy (6 ln) ST. CROIX I094E 3.96 4 32.57 32.57 9.8 20.37 2.05 3.96 4 17

S016851 Seg/Urb; Fwy in intchng area (4 ln) ST. CROIX I094W 245.45 245.99 5.95 21.41 10.59 19.25 3.3 245.89 245.99 18






S020372 Seg/Urb; Fwy (4 ln) DUNN I094W 205.49 206.68 5.15 23.23 4.21 16.83 2.36 205.49 205.59 24

S013918 Seg/Urb; Fwy (4 ln) EAU CLAIRE US053S 138.24 139.54 3.9 27.46 2.81 16.82 2.02 139.44 139.54 25



S014592 Seg/Urb; Fwy (6 ln) ST. CROIX I094E 0 0.57 9.9 17.37 13.05 16.26 2.62 0 0.1 28


S011315 Seg/Urb; One-way arterial CHIPPEWA SR124S 0.98 1.04 17.77 17.77 8.92 15.79 2.61 0.98 1.04 30

S003144 Seg/Urb; 2-lane arterial DUNN SR029E 47.23 48.36 5.53 18.15 2.41 15.63 2.65 47.23 47.33 31

S003106 Seg/Urb; 2-lane arterial PIERCE SR029E 10.76 11.68 6.79 16.13 6.5 15.5 2.92 11.16 11.26 32


90

S014816 Seg/Rur; Fwy (4 ln) DUNN I094W 197.29 198.7 7.86 58.65 3.51 15.4 0.72 197.29 197.39 34

S005690 Seg/Urb; 2-lane arterial JACKSON SR054E 40.53 40.59 16.8 16.8 4.77 15.14 2.63 40.53 40.59 35




S014803 Seg/Urb; Fwy (4 ln) EAU CLAIRE I094W 181.96 182.86 4.46 21.12 3.37 14.24 1.84 182.56 182.66 39

S009056 Seg/Urb; One-way arterial CHIPPEWA SR124N 5.52 5.63 15.51 14.93 7.59 13.69 2.43 5.52 5.62 40


S016843 Seg/Urb; Fwy (6 ln) ST. CROIX I094E 4 4.14 12.41 15.2 9.8 13.49 2 4.04 4.14 42

S000845 Seg/Urb; 2-lane arterial EAU CLAIRE US012E 73.12 73.61 4.94 14.11 5.18 13.39 2.48 73.51 73.61 43






S014618 Seg/Urb; Fwy (4 ln) DUNN I094E 41.78 42.68 6.1 16.9 4.21 12.63 1.77 41.78 41.88 49

S006526 Seg/Rur; 2-lane BARRON US063N 79.58 80.06 6.67 26.02 2.9 12.61 1.06 79.96 80.06 50




S016841 Seg/Urb; Fwy in intchng area (6 ln) ST. CROIX I094E 3.42 3.96 6.22 12.61 9.75 11.85 1.83 3.42 3.52 54

S020379 Seg/Rur; Fwy (4 ln) ST. CROIX I094E 6 7.13 5.77 36.93 3.99 11.83 0.61 6.9 7 55





S011569 Seg/Urb; 2-lane arterial PIERCE SR029E 11.7 12.14 8.71 12.1 4.4 11.37 2.08 11.9 12 60

91







S001295 Seg/Urb; 2-lane arterial ASHLAND SR013N 238.45 239.06 4.3 12.1 2.55 10.65 1.82 238.45 238.55 67

S006597 Seg/Rur; 2-lane ST. CROIX SR064E 0.38 0.81 6.52 20.01 3.09 10.47 0.91 0.38 0.48 68

S006444 Seg/Rur; 2-lane PIERCE US063N 1.44 1.63 10.53 20.01 2.98 10.25 0.88 1.53 1.63 69

S013981 Seg/Urb; Fwy (4 ln) CHIPPEWA US053S 127.9 128.14 11.44 19.01 1.99 10.21 1.04 128 128.1 70


S014624 Seg/Rur; Fwy (4 ln) DUNN I094E 40.16 40.89 6.25 34.75 3.35 9.87 0.45 40.76 40.86 72



S020381 Seg/Rur; Fwy (4 ln) ST. CROIX I094E 8.16 9.17 7.53 28.24 3.99 9.76 0.5 8.96 9.06 75

S013129 Seg/Urb; 2-lane arterial JACKSON US012E 123.22 123.57 4.03 10.08 5.3 9.7 1.8 123.47 123.57 76



S011584 Seg/Urb; 2-lane arterial PIERCE SR035N 190.99 191.84 4.98 10.08 4.78 9.62 1.77 191.19 191.29 79

S006596 Seg/Rur; 2-lane ST. CROIX SR064E 0 0.38 7.9 16.01 3.7 9.61 0.92 0.28 0.38 80

S019684 Seg/Rur; 2-lane ST. CROIX SR035N 210.87 212.05 6.45 18.01 3.03 9.48 0.82 211.57 211.67 81

S006721 Seg/Rur; 2-lane TAYLOR SR064E 113.4 113.47 22.87 22.87 2.82 9.45 0.63 113.4 113.47 82

S005641 Seg/Rur; 2-lane BUFFALO SR054E 0 0.8 4 18.01 2.97 9.38 0.8 0.7 0.8 83

S014679 Seg/Rur; Fwy (4 ln) ST. CROIX I094W 239.27 240.19 7.32 26.07 3.99 9.24 0.48 239.37 239.47 84


S013948 Seg/Urb; Fwy (4 ln) CHIPPEWA US053N 94.41 94.65 7.04 16.9 1.99 9.19 0.94 94.41 94.51 86

S000055 Seg/Urb; 2-lane arterial ASHLAND US002E 70.55 71.04 4.11 10.08 2.86 9.08 1.58 70.55 70.65 87

92



S000363 Seg/Rur; 2-lane PIERCE US010E 17.31 17.5 10.53 18.01 2.76 8.99 0.73 17.4 17.5 90

S009312 Seg/Urb; 2-lane arterial ASHLAND SR137E 5.42 5.97 3.3 10.08 2.47 8.89 1.51 5.52 5.62 91

S014606 Seg/Rur; Fwy (4 ln) ST. CROIX I094E 23.1 24.41 5.47 28.24 3.44 8.71 0.4 23.9 24 92

S014825 Seg/Urb; Fwy (4 ln) JACKSON I094E 113.8 114.83 3.28 12.67 3.02 8.68 1.07 114 114.1 93






S013917 Seg/Urb; Fwy (4 ln) EAU CLAIRE US053N 82.98 84.29 2.58 12.67 2.81 8.42 1.01 83.18 83.28 99


S006478 Seg/Rur; 2-lane ST. CROIX US063N 32.45 33.45 3.4 20.01 2.13 8.34 0.58 32.85 32.95 101


S001156 Seg/Rur; 2-lane CLARK SR013N 113.4 114.4 5.39 16.01 2.77 8.19 0.67 113.9 114 103



S000846 Seg/Rur; 2-lane EAU CLAIRE US012E 73.61 74.04 7.45 18.01 2.27 7.97 0.58 73.61 73.71 106





S001178 Seg/Rur; 2-lane TAYLOR SR013N 127.67 128.18 9.03 18.01 2.24 7.9 0.57 127.67 127.77 111



S002645 Seg/Urb; 2-lane arterial DUNN SR025N 36.55 37 5.82 8.07 5.1 7.82 1.45 36.55 36.65 114

93





S011572 Seg/Urb; 2-lane arterial PIERCE SR065N 10.81 11.47 1.83 8.07 4.43 7.72 1.41 11.31 11.41 119

S014878 Seg/Urb; Fwy (4 ln) JACKSON I094W 133.83 133.97 9.05 10.56 3.3 7.71 0.99 133.87 133.97 120


S019680 Seg/Urb; Fwy (4 ln) CHIPPEWA SR029E 68.6 68.82 6.72 12.67 2.28 7.65 0.84 68.7 68.8 122





S006540 Seg/Rur; 2-lane WASHBURN US063N 100.88 101.75 4.14 14.01 2.91 7.58 0.64 101.18 101.28 127

S008464 Seg/Rur; Fwy (4 ln) EAU CLAIRE I094E 79.83 81.16 4.08 28.24 2.88 7.55 0.3 80.63 80.73 128






S020102 Seg/Rur; 2-lane PEPIN US010E 45.25 46.44 3.2 16.01 2.34 7.38 0.54 45.25 45.35 134




S008479 Seg/Rur; 2-lane TREMPEALEAU SR095E 18.1 18.75 5.54 18.01 1.95 7.22 0.47 18.65 18.75 138

S004013 Seg/Rur; 2-lane PIERCE SR035N 190.81 190.99 12.23 16.01 2.25 7.2 0.52 190.89 190.99 139



94



S014826 Seg/Urb; Fwy in intchng area (4 ln) JACKSON I094E 114.83 115.33 4.28 8.56 4.57 7.1 0.96 114.83 114.93 144




S014614 Seg/Rur; Fwy (4 ln) ST. CROIX I094E 30.42 31.47 3.52 21.72 3.25 7 0.31 30.82 30.92 148




S006722 Seg/Rur; 2-lane TAYLOR SR064E 113.47 113.53 16.68 16.68 2.77 6.85 0.4 113.47 113.53 152

S000820 Seg/Rur; 2-lane DUNN US012E 51.54 52.49 3.16 16.01 2.08 6.84 0.47 51.54 51.64 153

S006443 Seg/Rur; 2-lane PIERCE US063N 0 1.44 2.5 12.01 2.98 6.84 0.58 0.3 0.4 154

S020007 Seg/Urb; Fwy in intchng area (4 ln) EAU CLAIRE US053N 84.59 85.47 2.19 8.56 4.1 6.81 0.89 84.69 84.79 155


S013548 Seg/Urb; Fwy (4 ln) CHIPPEWA SR029W 170.72 171.01 6.55 12.67 1.8 6.78 0.66 170.91 171.01 156






S007590 Seg/Rur; 2-lane CLARK SR073N 181.67 181.93 6.16 16.01 1.97 6.6 0.44 181.77 181.87 163




S008483 Seg/Rur; 2-lane TREMPEALEAU SR095E 18.95 20.12 2.57 12.01 2.78 6.56 0.54 19.15 19.25 167


95




S000029 Seg/Rur; 2-lane BAYFIELD US002E 51.21 52.21 2.8 18.01 1.67 6.49 0.38 51.21 51.31 172

S001182 Seg/Rur; 2-lane TAYLOR SR013N 130.21 130.82 3.61 14.01 2.24 6.47 0.46 130.21 130.31 173

S014828 Seg/Urb; Fwy (4 ln) JACKSON I094E 115.45 116.17 3.52 8.45 3.3 6.42 0.82 115.55 115.65 174


S000121 Seg/Rur; 2-lane POLK US008E 19.08 20.09 1.78 14.01 2.21 6.41 0.46 19.28 19.38 176




S020017 Seg/Urb; Fwy (4 ln) EAU CLAIRE US053S 135.05 136.27 1.04 8.45 3.23 6.37 0.81 136.17 136.27 179




S009061 Seg/Urb; One-way arterial CHIPPEWA SR124N 5.91 6.16 5.12 6.4 6.11 6.34 1.08 5.91 6.01 184








S019301 Seg/Rur; Fwy in intchng area (4 ln) JACKSON I094W 121.57 121.81 6.25 13.13 4.06 6.28 0.29 121.71 121.81 192


S006604 Seg/Rur; 2-lane ST. CROIX SR064E 12.01 12.51 4.8 16.01 1.82 6.26 0.39 12.11 12.21 194


SafetyAnalyst Evaluation and Systems

Requirement Assessment

Module 3: Economic Analysis

Andrea Bill, Research Assistant





July, 2011

i

DISCLAIMER

This research was funded by the Wisconsin Department of Transportation. The contents

of this report reflect the views of the authors who are responsible for the facts and accuracy of

the data presented herein. The contents do not necessarily reflect the official views of the

Wisconsin Department of Transportation at the time of publication.


Transportation in the interest of information exchange. The United States Government assumes

no liability for its contents or use thereof. This report does not constitute a standard,

specification, or regulation.




ii

TABLE OF CONTENTS

I. PROCEDURES ......................................................................................................... 3

Intersection C|014W|019098|026060 (US-14 & 4th St., La Crosse) .......................................... 4

Intersection C|157E|009759|002160 (WI-157 & WI-16, La Crosse) ......................................... 6

II. RESULTS AND COMMENTS ................................................................................... 8

3

I. PROCEDURES

In a previous evaluation, 36 intersections in the SW region were selected using Module 1

Network Screening of SafetyAnalyst. In this report, two intersections of La Crosse out of

the 36 intersections are analyzed. Both intersections are of type 4-leg minor road STOP

controlled. The intersections are US-14 @ 4th

St. and WI-157 @ WI-16.

Using Module 2 Diagnosis of SafetyAnalyst, several countermeasures are proposed for

each intersection. Out of these countermeasures, we select three for the first intersection

and four for the second intersection for economic analysis using Module 3.

Module 3 Economic Analysis provides four criteria for the evaluation, namely,

• Cost-effectiveness

• EPDO-Based Cost-effectiveness

• Benefit-cost Ratio

• Net Benefit

The first two criteria do not attribute monetary costs to accidents. The third one is based

on the ratio of the benefit of a project to its cost and the fourth is based on the difference.

In this report, we use the Benefit-Cost ratio as the criterion, which agrees with former

Project Evaluation Factor (PEF) analysis and makes a comparison between the two

methods reasonable.

Default parameters are used in all analyses.

4

Intersection C|014W|019098|026060 (US-14 & 4th St., La Crosse)

Crashes Summary

Ftl. Inj. A Inj. B Inj. C PD Total

Right Angle

Left Turn - Main Road 5 11 16

Rear End 4 4

Sideswipe-Opposite

Sideswipe-Same 6 6

Merging

Head On 1 1

Hit Object

Run Off Road

Fail to Negotiate Curve

Pedestrian Collisions

Miscellaneous 1 2 3

Crash Totals 6 24 30

5

Countermeasures

These countermeasures are selected for analysis:

1. Install left-turn lane;

2. Install multilane roundabout; and

3. Install traffic control signals, if warranted.

Results Summary

1. SafetyAnalyst recommends the first countermeasure (to install LT lane), which

has the highest B/C ratio;

2. The PEF of the countermeasure is 1.25, based on the Excel calculation.

6

Intersection C|157E|009759|002160 (WI-157 & WI-16, La Crosse)

Crashes Summary

Ftl. Inj. A Inj. B Inj. C PD Total

Right Angle

Left Turn - Main Road

Rear End 1 13 23 37

Sideswipe-Opposite

Sideswipe-Same 2 2

Merging

Head On 1 2 3

Hit Object

Run Off Road



Miscellaneous 1 1 2 4

Crash Totals 15 29 46

7

Countermeasures

These countermeasures are selected for analysis:

1. Install left-turn lane;

2. Install multilane roundabout;

3. Improve pavement friction; and

4. Install traffic control signals, if warranted.

Results Summary

1. SafetyAnalyst recommends the third countermeasure (to improve pavement

friction), which has the highest B/C ratio;

2. The PEF of the countermeasure is 4.02, based on the Excel calculation.

8

II. RESULTS AND COMMENTS

The results from SafetyAnalyst and the PEFs are summarized in the following table.

Intersection

ID Route Countermeasure

Construction

Cost

Cost

Effectiveness

Cost

Effectiveness

EPDO

Benefit

Cost

Ratio

Net Benefit PEF

2 157E Install left-turn lane $ 280,000 $ 2,857 $ 256 10.47 $ 2,650,228

2 157E Install multilane

roundabout $ 300,000 $ 4,930 $ 178 15.07 $ 4,222,330

2 157E Improve pavement

friction $ 60,000 $ 1,479 $ 140 19.15 $ 3,324,586 4.02

2 157E Install traffic control

signals, if warranted $ 100,000 $ 3,472 $ 329 8.16 $ 1,198,946

1 014W Install left-turn lane $ 140,000 $ 2,463 $ 362 7.40 $ 895,812 1.25

1 014W Install multilane

roundabout $ 300,000 $ 8,500 $ 523 5.13 $ 1,238,811

1 014W Install traffic control

signals, if warranted $ 100,000 $ 5,986 $ 926 2.89 $ 317,180

The two applications give somehow different results, which might be caused by the

following reasons.

1. They use different default values in the analysis.

SafetyAnalyst

• Accident costs:

o Fatal: $5,800,000

o Severe injury: $402,000

o Non-incapacitating injury: $ 80,000

o Possible injury: $ 42,000

o Property damage only: $4,000


• Analysis years: 20 years

PEF

• Accident costs:

Fatal 2+: $100,000

Injury A with Fatal: $90,000

9

Injury A 2+: $80,000

Fatal: $85,000

Injury A: $65,000

Injury B: $40,000

Injury C: $20,000

Property: $10,000


• Analysis years: 10 years

2. They use different formulas in the analysis.

In addition, SafetyAnalyst provides far more flexibilities. Evaluation using this

application can be based on four different criteria, it can automatically select the optimal

countermeasure for a given site or project, and it can even determine the optimal

combination of various sites and countermeasures, given that the budget is limited.

SafetyAnalyst Evaluation and Systems

Requirement Assessment - Economic

Assessment of HSIP Applications Using

SafetyAnalyst

Module 2: Diagnosis and Countermeasure Selection

Andrea Bill, Traffic Safety Engineering Research Program Manager


David A. Noyce, Ph.D., P.E.




July 2011

DISCLAIMER

This research was funded by the Wisconsin Department of Transportation. The

contents of this report reflect the views of the authors who are responsible for the facts

and accuracy of the data presented herein. The contents do not necessarily reflect the

official views of the Wisconsin Department of Transportation at the time of publication.


Transportation in the interest of information exchange. The United States Government

assumes no liability for its contents or use thereof. This report does not constitute a

standard, specification, or regulation.

The United States Government does not endorse products or manufacturers. Trade

and manufacturers’ names appear in this report only because they are considered essential

to the object of the document.

TABLE OF CONTENTS

I. INTRODUCTION ........................................................................................... 1

Highway Safety Improvement Program (HSIP) ......................................................................... 1

SafetyAnalyst .............................................................................................................................. 1

The PEF Tool .............................................................................................................................. 2

II. DATA USED FOR THE EVALUATION .......................................................... 3

Data Used in SafetyAnalyst ........................................................................................................ 3

HSIP Applications Used for the Evaluation ............................................................................... 3

III. USING SAFETYANALYST ANALYTICAL TOOL ........................................ 6

IV. EVALUATION OF HSIP APPLICATIONS ................................................. 11

(a) USH 51/Stoughton Rd. @ Pflaum Rd., City of Madison, Dane Co.................................... 11

(b) USH 51/S. Stoughton Rd. @ E. Buckeye Rd., City of Madison, Dane Co. ....................... 14

(c) STH 60 @ CTH P, Town of Rubicon, Dodge Co. .............................................................. 16

(d) STH 60 @ CTH E, Town of Hustisford, Dodge Co. .......................................................... 18

(e) USH 61 @ STH 129, Town of North Lancaster, Grant Co. ............................................... 20

(f) STH 16 @ CTH F, Town of Ixonia, Jefferson Co. .............................................................. 22

(g) USH 18 @ STH 89 (west intersection), Town of Jefferson, Jefferson Co. ........................ 24

(h) USH 18 @ STH 89 (east intersection), Town of Jefferson, Jefferson Co. ......................... 26

(i) STH 58 @ STH 82, City of Mauston, Juneau Co. ............................................................... 28

(j) USH 12 @ CTH HH/N, Town of Lyndon Station, Juneau Co. ........................................... 30

(k) USH 45 @ CTH B, Town of Neva, Langlade Co. .............................................................. 32

(l) USH 51 @ North Star Rd., Town of Merrill, Lincoln Co. .................................................. 34

(m) STH 100 @ 51 St., City of Brown Deer, Milwaukee Co................................................... 36

(n) STH 16 @ STH 71, City of Sparta, Monroe Co. ................................................................ 38

(o) STH 26 @ Plainview Dr./Washburn St., Town of Nekimi, Winnebago Co. ...................... 40

(p) STH 162 (H Hunt Rd. to Kammel Rd.), Town of Washington, La Crosse Co. .................. 42

(q) STH 60 (West of Gotham), Town of Orion, Richland Co. ................................................. 44

V. CONCLUSIONS AND RECOMMENDATIONS .............................................. 46

1

I. INTRODUCTION

The goal of this report is two-fold:

• Verify the feasibility of using SafetyAnalyst to evaluate Highway Safety Improvement

Program (HSIP) project applications;

• Compare SafetyAnalyst with the Project Evaluation Factor (PEF) Tool developed by

Wisconsin Department of Transportation (WisDOT).

Highway Safety Improvement Program

The main purpose of HSIP is to establish policy for the development and implementation

of a comprehensive highway safety program in each state including components for planning,

implementation, and evaluation of safety programs and projects. These components consist of

processes developed by states and approved by Federal Highway Administration (FHWA). To

qualify for funding for these programs, states must have an approved Strategic Highway Safety

Plan (SHSP) that provides directions and guidelines for allocating their funds. SafetyAnalyst has

been designed to accommodate these needs.

SafetyAnalyst

SafetyAnalyst is a software package composed of a set of state-of-the-art analytical tools

for use in the decision-making process to identify and manage a system-wide program of site-

specific improvements to enhance highway safety by cost-effective means and the only one

being undertaken at the national level. SafetyAnalyst implements part of the Highway Safety

Manual (HSM) which aims at estimating highway safety performance under varying conditions

in the same sense as the Highway Capacity Manual (HCM). The Highway Safety Manual is

intended to provide a quantitative basis for estimating the safety performance of an existing

highway or street and for estimating the effects of proposed improvement projects. Part B of the

HSM provides the basic concepts and steps which form the basis for the SafetyAnalyst

Analytical Tool used to perform safety calculations. Highway agencies will be able to use

SafetyAnalyst to investigate the potential benefits of specific safety improvements and conduct a

thorough economic analysis.

SafetyAnalyst focuses on identifying the need for improvements at specific roadway

sites, identifying the most appropriate improvements for those sites, and making cost-effective

choices to set priorities among the potential improvements. The software can also make reliable

estimates of the safety effectiveness of countermeasures that are implemented by highway

agencies. SafetyAnalyst addresses site-specific safety improvements that involve physical

modifications to the highway system. SafetyAnalyst integrates all parts of the safety

management process and streamlines all steps of the process that have been performed manually

in the past. The general safety management process can be described in six main steps:

Step 1: Identification of sites with potential for safety improvement;

2

Step 2: Diagnosis of the nature of safety problems at specific sites;

Step 3: Selection of countermeasures at specific sites;

Step 4: Economic appraisal for sites and countermeasures under consideration;

Step 5: Priority rankings of improvement projects; and

Step 6: Safety effectiveness evaluation of implemented countermeasures.

The SafetyAnalyst Analytical Tool is comprised of four modules which, when packaged

together, incorporate the six main steps for highway safety management specified in the HSM:

Module 1: Network screening (Chapter 4 of HSM)

Module 2: Diagnosis and countermeasure selection (Chapters 5 and 6 of HSM)

Module 3: Economic appraisal and priority ranking (Chapters 7 and 8 of HSM)

Module 4: Countermeasure evaluation (Chapter 9 of HSM)

This evaluation is based on SafetyAnalyst ver. 4.0.0-Jan. 21, 2010.

The Project Evaluation Factor Tool

WisDOT developed and Excel-based PEF Tool to evaluate the effectiveness of proposed

highway safety projects, based on the criterion of the PEF. The tool evaluates expected crash

reduction against the estimated project cost at the site to compute a so-called PEF as the criterion.

Expected crash reduction is calculated based upon historical crash data (usually five years) and

the expected crash reduction rate if the countermeasure is applied. Crashes of different severities

are attributed with different values, ranging from $100,000 for a fatal crash down to $10,000 for

a property-damage only crash.

In this report, results of the PEF tool were compared with results from SafetyAnalyst using

Module 2 and Module 3 with available information.

3

II. DATA USED FOR THE EVALUATION

Data Used in SafetyAnalyst

SafetyAnalyst relies on the road inventory, traffic, crash history, and implemented

projects data to perform analysis of safety improvements and projects. Data for the State Trunk

Network (STN) system in Wisconsin for the years 2003-2007 were received from WisDOT and

processed by SafetyAnalyst. SafetyAnalyst has strict data requirements in terms of format and

completeness, therefore a number of road segments, intersections, and crashes were invalidated

by SafetyAnalyst during data post-processing. The reasons for invalidating sites and data

included (but were not limited to): lack of AADT data for road segments and intersections;

missing geometric information for assigning a SafetyAnalyst default site subtype; missing

intersection leg information; missing or incomplete crash location information to assign crashes

to road segments or intersections; and lack of detailed traffic control information, etc. Locations

considered invalid by SafetyAnalyst are not included in any analysis performed by SafetyAnalyst

until the missing elements are provided. A summary of valid sites processed by SafetyAnalyst

based on STN data provided by WisDOT is presented in Table 1.

Table 1 Summary of SafetyAnalyst Valid Sites Data

Element Total Number Number of Valid Elements % of Valid

Elements


Ramps 0 0 N/A


Crashes 271499 247137 91.0

HSIP Project Applications Used for the Evaluation

Of 23 HSIP projects received for evaluation, seventeen projects were ultimately

evaluated, as shown in detail in Section IV of this report. The other six projects were not

evaluated due to either lack of data or the limitations of SafetyAnalyst as described below:

• Four projects were not on the State Trunk Network and required data were not available

for SafetyAnalyst;

• One project was a highway interchange, and currently SafetyAnalyst is not capable of

analyzing interchanges;

• One project location included both an interchange and a roadway segment. Currently,

SafetyAnalyst cannot combine different types of sites (intersections, segments, and ramps)

for combined evaluation, except segments of the same subtype (SafetyAnalyst site-

subtypes include e.g. two-lane rural road, four-lane urban divided road, etc).

Table 2 shows all 17 HSIP projects evaluated by SafetyAnalyst. Table 3 shows the other

six projects that were not evaluated.

4

Table 2 List of HSIP Project Locations Evaluated

Project ID County Municipality Location Proposed Countermeasures Site Type

5410-02-71 Dane Madison (C) USH 51/Stoughton Rd. @ Pflaum

Rd. Improving of geometrics and signals Intersection

5410-02-72 Dane Madison (C) USH 51/S. Stoughton Rd. @ E.

Buckeye Rd. Improving of geometrics and signals Intersection

3042-00-73 Dodge Rubicon (T) STH 60 @ CTH P Install a roundabout Intersection

3889-00-71 Dodge Hustisford (T) STH 60 @ CTH E Install a roundabout Intersection

1650-01-79 Grant North Lancaster (T) USH 61 @ STH 129 Install medians and left turn lanes. Upgrade signing and

markings. Intersection

1370-02-77 Jefferson Ixonia (T) STH 16 @ CTH F Install a roundabout. Intersection

3080-03-72 Jefferson Jefferson (T) USH 18 @ STH 89 (west

intersection) Right turn lane. Intersection

3080-03-74 Jefferson Jefferson (T) USH 18 @ STH 89 (east

intersection) Right turn lane. Intersection

5010-01-01 Juneau Mauston (C) STH 58 @ STH 82 Left turn lane, signal, and median Intersection

5880-03-75 Juneau Lyndon Station (T) USH 12 @ CTH HH/N Remove parking and install STOP sign. Intersection

1602-13-70 Langlade Neva (T) USH 45 @ CTH B Realignment and flashing beacons Intersection

1176-24-70 Lincoln Merrill (T) USH 51 @ North Star Rd Install an overpass Intersection

Milwaukee Brown Deer (C) STH 100 @ 51 St Left turn lane offset and signals Intersection

7016-00-72 Monroe Sparta (C) STH 16 @ STH 71 Install a roundabout. Intersection

1110-05-71 Winnebago Nekimi (T) STH 26 @ Plainview Dr/Washburn

St Installation of traffic signals Intersection

5820-01-71 La Crosse Washington (T) STH 162 (H Hunt Rd. to Kammel

Rd.) Realign the roadway. New marking and signing. Segment

5190-07-71 Richland Orion (T) STH 60 (West of Gotham) Realign the roadway. New marking and signing. Segment

5

Table 3 List of HSIP Project Locations Not Evaluated

Project ID County Municipality Location Proposed Countermeasures Site Type Invalidity

6747-04-02 Portage Plover (V) CTH B @ Hoover Ave. Turning lanes, signal upgrade,

and speed reduction Intersection Not STN

1001-03-04 Rock Janesville (C) IH 39 @ STH 11

Replace the cloverleaf

interchange with a full diamond

interchange.

Interchange Interchange

1204-02-09 Iowa Ridgeway (T) USH 18/151 (CTH HHH to CTH BB) Right and left turn lanes. Segment and

Intersection

Intersection

and segment

6635-01-03 Juneau Germantown (T) CTH G (around Water St.) Replace the cable guard system

with Safence system. Segment Not STN

6635-01-02 Juneau Armenia CTH G/County Line Rd. Realign the roadway. Segment and

Intersection Not STN

6844-00-00 Waupaca Lind (T) CTH E @ CTH EE Shoulder widening Segment Not STN

6

III. USING SAFETYANALYST ANALYTICAL TOOL

SafetyAnalyst Analytical Tool

This section describes the workings of the SafetyAnalyst Analytical Tool which is used

to perform safety evaluations of highway components. The first step in the analysis is to create a

workbook, which contains a list of projects of sites (road segments, intersections, or ramps)

where safety analysis will be performed. Each workbook contains site lists comprised of single

or multiple locations depending upon user needs, e.g. a project involving several contiguous

segments. For the purpose of analysis in this report, 17 site lists were created each representing

one of the 17 projects selected for evaluation which included 15 intersections and 2 road

segments, as shown in Figure 1. The site lists provide the analyst with opportunity to verify

information for each site, such as site inventory properties, traffic history, and crash history.

Figure 1 SafetyAnalyst Analytical Tool – Site List and Properties

In the next step, Module 2 Diagnosis of SafetyAnalyst is applied to each project to

determine the nature of safety issues at the selected site. Crash history is analyzed and several

countermeasures are proposed for each site. However, the analyst can skip this step and go

directly to Module 3 to select and evaluate the appropriate countermeasures if need be.

Countermeasures for specific sites/projects are selected either with the aid of Module 2 or

directly in Module 3 as shown in Figure 2. The detailed parameters for specific countermeasures

such as cost, Crash Modification Factor (CMF), maintenance costs, service life etc. can be

7

modified for each project as shown in Figure 3. The evaluation performed in this report makes

use of default values provided by SafetyAnalyst however such values can be easily modified

based on the analyst’s choice. SafetyAnalyst also provides the ability to combine several

countermeasures together into one countermeasure with appropriate parameters. It should be

noted that SafetyAnalyst advises caution in combining more than 3 countermeasures as it is

extremely difficult to obtain reliable CMF in such cases.

Figure 2 Selecting Individual or Combined Countermeasures

8

Figure 3 Modifying Parameters of Individual or Combined Countermeasures

Once countermeasures and their parameters are selected, the next step is to select the

performance measures, measures of effectiveness, or the criteria to be used to evaluate the safety

effectiveness of the countermeasures for the proposed projects. Module 3 Economic Analysis of

SafetyAnalyst provides four criteria for safety evaluation of proposed countermeasures as shown

in Figure 4 and listed below:

• Cost-effectiveness

• Equivalent Property Damage Only (EPDO) -Based Cost-effectiveness

• Benefit-Cost Ratio

• Net Benefit

9

Figure 4 Selection of Evaluation Criteria or Measure of Effectiveness

The first two criteria do not attribute monetary costs to crashes. The third and fourth are

based on project benefits and cost by calculating the ratio and difference between the two values

respectively. The Benefit-Cost ratio was selected as the performance measure to compare the

safety evaluation performed by SafetyAnalyst with the evaluation results of the PEF tool. The

reason was because the definition of the Benefit-Cost ratio best matches the definition of the PEF

value as calculated by the Excel-based PEF tool, making a comparison between the two

evaluation tools reasonable.

Evaluation Methodology

The goal of this research was to compare the results of SafetyAnalyst evaluation of HSIP

project applications with the results of PEF tool as used currently by WisDOT. A two-pronged

approach was used to make comparisons between the two tools.

• First, individual and combined countermeasures, matching those described in the HSIP

application and PEF tool as close as possible for each project were evaluated by

SafetyAnalyst using default parameter values provided in the SafetyAnalyst library e.g.

CMF, construction cost, service life.

• Second, the default parameter values in SafetyAnalyst were replaced with CMF,

construction cost, service life etc. parameter values from the HSIP applications to

perform evaluation of countermeasures using PEF values but SafetyAnalyst methodology.

10

The reason for the first comparison was to assess the performance of SafetyAnalyst as a

standalone safety evaluation tool with minimal user input or modification to observe the results

of SafetyAnalyst methodology under least ideal conditions. The second comparison was more

critical in making direct comparison between SafetyAnalyst and the PEF tool. It should be noted

that in both the comparisons, crash cost values were modified in SafetyAnalyst to match those

used in the PEF tool as shown below:

o Cost of crashes:

� Fatal: $100,000

� Injury A: $80,000

� Injury B: $40,000

� Injury C: $20,000

� PDO crashes: $10,000

o Crash EPDO weight:

� Fatal: 10

� Injury A: 8

� Injury B: 4

� Injury C: 2

� PDO crashes: 1

Other parameters that were modified in SafetyAnalyst to match the values in PEF tool

were the discount rate (3%) and the analysis period (10 years). Some CMF values are provided

as default in SafetyAnalyst. In cases where CMF values were not provided by SafetyAnalyst,

values were obtained from various other sources, e.g. The Crash Modification Factors

Clearinghouse website, HSM, Desktop Reference for Crash Reduction Factors, etc.

Although every effort was made to make the comparison as close as possible, there were

certain limitations primarily related to the data quality. The crash, inventory, and traffic data

used in SafetyAnalyst had missing elements. Hence, data for each project were examined

manually and modified to best reflect the ground conditions and make their use consistent with

the PEF tool. Changes included modifications of site geometric properties; using the traffic

volumes and growth rates provided in the original PEF analysis which was deemed more

credible, etc.

The next section describes detailed analysis of each HSIP project and evaluation results

and comparison. The SafetyAnalyst countermeasures were selected to match those proposed in

the original application as closely as possible. Note that because most of the proposed

countermeasures were indeed combinations of several specific countermeasures and not all the

specific countermeasures are included in the default library of SafetyAnalyst, some of them

might not be included in the evaluation.

11

IV. EVALUATION OF HSIP APPLICATIONS

(a) USH 51/Stoughton Rd. @ Pflaum Rd., City of Madison, Dane County

Figure 5 USH 51/Stoughton Rd. @ Pflaum Rd., City of Madison, Dane County

Crash Summary (4 years, 2005-2008)

Table 4 2005-2008 Crash Summary at USH 51/Stoughton Rd. @ Pflaum Rd.

Fatal Inj. A Inj. B Inj. C PD Total

Right Angle 2 6 12 20

Left Turn - Main Road 1 1 2

Rear End 2 9 31 57 99

Sideswipe-Opposite 1 1

Sideswipe-Same 4 4

Merging

Head On 1 2 3

Hit Object 1 6 7

Run Off Road

Fail to Negotiate Curve 1 1


Miscellaneous 1 1

Crash Totals 3 12 38 85 138

Location Description (from HSIP Application)

12

USH 51 at Pflaum Road is four-lane divided roadway with turn lanes and traffic signals.

The posted speed limit on USH 51 is 55 mph. In the 4 year period (2005 – 2008), 138 crashes

were reported. The most common type of crash by far is rear end crashes. Rear end crashes

accounted for approximately 70% of the crashes (99 of the 138 crashes). Detailed analysis of the

data indicates that more than 90% of these rear end crashes occurred within 200’ of the

intersection. This shows that the rear end crashes are not occurring at the back of the queue, but

seem to be occurring as drivers at or near the intersection react to the signalized control of the

intersection.

Proposed Countermeasures (from HSIP Application)

The proposed project consists of improving the intersection’s geometrics and installing

signal heads over each traffic lane by mounting them on mono-tube arms. The detection loops

will be moved back from the intersection to a distance of 6 seconds at the current posted speed

(they are currently at 5 seconds). Improvements to intersection geometrics include reconfiguring

channelization islands on Pflaum to allow a left turn phase from both legs of Pflaum at the same

time.

Summary of Safety Evaluation Comparison Results

Table 5 shows the comparison between SafetyAnalyst countermeasure evaluation results

and PEF value. Column 1 to 4 indicate the parameter values required for evaluating

countermeasures and column 5 to 8 shows the evaluation criteria or performance measures as

calculated by SafetyAnalyst. The last column shows the PEF value from the excel-based PEF

tool developed by WisDOT. The rows show the parameters and performance measures for

individual or combined countermeasures as indicated in the HSIP project applications and

evaluated by SafetyAnalyst. Note that the parameter values used in all rows except the last one

are default SafetyAnalyst values. The parameter values used in the last row were taken from the

HSIP project applications to calculate a Benefit-cost value using SafetyAnalyst that is directly

comparable with the PEF value. The evaluation result tables for subsequent projects are

structured in the same manner as Table 5.

Table 5 Comparison of SafetyAnalyst Countermeasure Evaluation Results with PEF at

USH 51/Stoughton Rd. @ Pflaum Rd.

Countermeasure CMF Fatal

CMF

Service

Life

Construction

Cost ($)

Cost

Effectiveness

($)

Cost

Effectiveness

EPDO ($)

Benefit

Cost

Ratio

Net

Benefit

($)

PEF

Install dilemma

detection

system

0.61 0.61 10 30,000 245 149 52.21 1,536,392

Provide positive

offset of

opposite left-

turn lanes

0.90 0.90 20 50,000 914 556 14.01 372,971

13

Convert signal

from pedestal-

mounted to

mast arm

0.51 0.56 20 130,000 485 307 25.35 1,814,721

CM above

combined 0.28 0.31 20 232,323 590 364 21.38 2,715,389

HSIP 0.62* n/a 10* 835,302* 7,037 4,276 1.82 685,303 2.67*

*Note: These values are taken from the HSIP project application form.

The first four rows in Table 5 show the evaluation results of individual and combined

countermeasures based on SafetyAnalyst default parameters indicating a very high Benefit-cost

value primarily due to the low cost estimates of the countermeasures. The last row shows the

SafetyAnalyst evaluation result of combined countermeasures based on parameter values

provided in the PEF spreadsheets associated with HSIP applications indicating a slightly less

(1.82) but very close Benefit-cost value to the PEF value (2.67). The reason the Benefit-cost

value is less than the PEF value is because SafetyAnalyst uses state-of-the-art Empirical Bayes

analysis method to account for the regression-to-the-mean effect which overestimates the safety

benefits as shown by the PEF value.

14

(b) USH 51/S. Stoughton Rd. @ E. Buckeye Rd., City of Madison, Dane County

Figure 6 USH 51/S. Stoughton Rd. @ E. Buckeye Rd., City of Madison, Dane County


Table 6 2005-2008 Crash Summary at USH 51/S. Stoughton Rd. @ E. Buckeye Rd.


Right Angle 1 2 5 8

Left Turn - Main Road 1 1 1 3

Rear End 2 11 34 68 115

Sideswipe-Opposite 1 1

Sideswipe-Same 5 5

Merging

Head On 2 2

Hit Object 1 3 3 7

Run Off Road 1 1



Miscellaneous 1 2 3



USH 51 at Buckeye Road is a divided four-lane roadway with turn lanes and traffic

signals. The posted speed limit on USH 51 is 55 mph. In the 4 year period (2005 – 2008), 146

15

crashes were reported. The most common type of crash by far is rear-end crashes. Rear-end

crashes accounted for over 75% of all crashes (115 of the 146 crashes). Detailed analysis of the

data indicates that 90% of these rear-end crashes are occurring within 200’ of the intersection.

This shows that the rear-end crashes are not occurring at the back of the queue, but seem to be

occurring as drivers at or near the intersection react to the signalized control of the intersection.


The proposed project consists of improving the intersection’s geometrics and installing

signal heads over each traffic lane by mounting them on monotube arms. The detection loops

will be moved back from the intersection to a distance of 6 seconds at the current posted speed

(they are currently at 5 seconds).


The first three rows in Table 7 show the evaluation results of individual and combined





(1.81) but very close Benefit-cost value to the PEF value (2.86).


USH 51/S. Stoughton Rd. @ E. Buckeye Rd.


CMF

Service

Life

Construction

Cost ($)

Cost

Effectiveness

($)

Cost

Effectiveness

EPDO ($)

Benefit

Cost

Ratio

Net

Benefit

($)

PEF

Install dilemma

detection

system

0.61 0.61 10 30,000 244 146 53.19 1,565,638

Convert signal

from pedestal-

mounted to

mast arm

0.51 0.56 20 130,000 483 302 25.80 1,848,453

CM above

combined 0.31 0.34 20 182,323 481 294 26.48 2,664,125

HSIP 0.63* n/a 10* 835,302* 7,169 4,303 1.81 676,872 2.86*


16

(c) STH 60 @ CTH P, Town of Rubicon, Dodge County

Figure 7 STH 60 @ CTH P, Town of Rubicon, Dodge County


Table 8 2004 – 2008 Crash Summary at STH 60 @ CTH P


Right Angle 1 3 6 6 3 19


Rear End 1 3 4

Sideswipe-Opposite

Sideswipe-Same 2 2

Merging

Head On

Hit Object

Run Off Road



Miscellaneous 1 3 4

Crash Totals 1 4 6 7 11 29


The STH 60 & CTH P intersection is a four-legged rural intersection in Dodge County.

CTH P is controlled by stop signs. Traffic volume on STH 60 is over 8,000 AADT and around

17

3,000 AADT on CTH P. Twenty-nine non-deer crashes were recorded from 2004 through 2008,

including one fatality and 4 incapacitating injuries. Two-thirds of the crashes are angle crashes.

Drivers attempting to make turns appear to be having trouble judging appropriate gaps.


A small roundabout will be installed and small strips of R/E are anticipated to be needed

on all quadrants.


The first row in Table 9 shows the evaluation results of countermeasure based on

SafetyAnalyst default parameters indicating a moderate Benefit-cost value primarily due to the

low cost estimates of the countermeasures. The last row shows the SafetyAnalyst evaluation

result of the roundabout based on parameter values provided in the PEF spreadsheets associated

with HSIP applications indicating a very small (0.17) Benefit-cost value to the PEF value (0.74).


STH 60 @ CTH P


CMF

Service

Life

Construction

Cost ($)

Cost

Effectiveness

($)

Cost

Effectiveness

EPDO ($)

Benefit

Cost

Ratio

Net

Benefit

($)

PEF

Install single-

lane roundabout 0.29 0.13 20 150,000 2,548 2,091 3.61 224,120

HSIP 0.40* 0.40* 10* 1,521,326* 53,344 45,255 0.17 (1,267,910) 0.74*


18

(d) STH 60 @ CTH E, Town of Hustisford, Dodge County

Figure 8 STH 60 @ CTH E, Town of Hustisford, Dodge County


Table 10 2003 – 2007 Crash Summary at STH 60 @ CTH E


Right Angle 1 1 1 1 1 5


Rear End 2 1 3

Sideswipe-Opposite

Sideswipe-Same 1 1

Merging

Head On

Hit Object

Run Off Road



Miscellaneous



This intersection has been experiencing severe crashes for some time and the entire

corridor has a history of severe crashes. The crash type are mostly angle and rear ends with 1 K,

3 A, 1 B and 2 PD crashes.

19


A roundabout will be installed at this location to control traffic movements and slow

traffic.


The first row in Table 11 shows the evaluation result of roundabout based on

SafetyAnalyst default parameters indicating a low Benefit-cost value primarily due to the small

number of crashes at this location. The last row shows the SafetyAnalyst evaluation result of the

roundabout installation based on parameter values provided in the PEF spreadsheets associated

with HSIP applications indicating a very low (0.10) Benefit-cost value to the PEF value (0.60).


STH 60 @ CTH E


CMF

Service

Life

Construction

Cost ($)

Cost

Effectiveness

($)

Cost

Effectiveness

EPDO ($)

Benefit

Cost

Ratio

Net

Benefit

($)

PEF

Install single-

lane roundabout 0.29 0.13 20 150,000 8,824 5,904 1.28 23,817

HSIP 0.26* 0.15* 10* 1,161,302* 114,485 78,184 0.10 (1,049,325) 0.60*


20

(e) USH 61 @ STH 129, Town of North Lancaster, Grant County

Figure 9 USH 61 @ STH 129, Town of North Lancaster, Grant County


Table 12 2003 – 2007 Crash Summary at USH 61 @ STH 129


Right Angle 1 1 1 3


Rear End 1 1

Sideswipe-Opposite

Sideswipe-Same

Merging

Head On 1 1

Hit Object

Run Off Road 1 1 3 5



Miscellaneous



A variety of intersection related crashes have occurred in this “T” intersection resulting in

0 K, 2 A and 2 B injury crashes. Crash types include run through, head on and angles. Currently

there is a substandard bypass lane at this intersection.

21


A raised median will be installed and a left turn lane on USH 61for protection of left turn

vehicles. All signings and markings will also be upgraded at the intersection.



countermeasures based on SafetyAnalyst default parameters indicating a mix of Benefit-cost

value due to low cost of countermeasures and small number of crashes. The last row shows the


provided in the PEF spreadsheets associated with HSIP applications indicating a very low (0.10)

Benefit-cost value to the PEF value (0.64).


USH 61 @ STH 129


CMF

Service

Life

Construction

Cost ($)

Cost

Effectiveness

($)

Cost

Effectiveness

EPDO ($)

Benefit

Cost

Ratio

Net

Benefit

($)

PEF

Install left-turn lane 0.56 0.45 20 50,000 7,904 4,100 1.84 24,083

Improve

visibility/retro-

reflectivity of

pavement markings

0.90 0.90 1 7,500 79,939 45,886 0.16 (55,061)

Improve visibility of

regulatory signs 0.90 0.90 10 500 607 348 21.67 10,335

Install median on

major road to restrict

left-turn maneuvers

at intersection

0.75 0.75 20 15,000 4,173 2,396 3.15 18,487

CM above combined 0.34 0.27 20 104,182 10,983 6,043 1.25 14,840

HSIP 0.67* 0.74* 10* 320,000* 119,262 74,343 0.10 (287,525) 0.64*


22

(f) STH 16 @ CTH F, Town of Ixonia, Jefferson County

Figure 10 STH 16 @ CTH F, Town of Ixonia, Jefferson County


Table 14 2004 – 2008 Crash Summary at STH 16 @ CTH F


Right Angle 1 1 1 2 5


Rear End 1 1 2 1 5

Sideswipe-Opposite

Sideswipe-Same 4 4

Merging 3 3

Head On 1 1

Hit Object 1 1

Run Off Road



Miscellaneous



A Total of 19 intersection related crashes are reported resulting in 1 K, 2 A, 5 B, 3 C & 8

PD crashes. Crash types are 8 angle, 5 sideswipe in same direction, 4 rear-end, 1 head on, and

run off road.

23


A roundabout will be installed at this location to help slow traffic and allow for safer

turning movement counts.


The first row Table 15 show the evaluation results of roundabout installation based on

SafetyAnalyst default parameters indicating a moderate Benefit-cost value primarily due to the

low cost estimates of the countermeasures. The last row shows the SafetyAnalyst evaluation

result of roundabout based on parameter values provided in the PEF spreadsheets associated with

HSIP applications indicating a very low (0.12) Benefit-cost value to the PEF value (0.56).


STH 16 @ CTH F


CMF

Service

Life

Construction

Cost ($)

Cost

Effectiveness

($)

Cost

Effectiveness

EPDO ($)

Benefit

Cost

Ratio

Net

Benefit

($)

PEF

Install single-

lane roundabout 0.29 0.13 20 150,000 6,970 3,222 2.34 115,386

HSIP 0.32* 0.15* 10* 1,591,326* 133,835 61,408 0.12 (1,395,808) 0.56*


24

(g) USH 18 @ STH 89 (West intersection), Town of Jefferson, Jefferson County

Figure 11 USH 18 @ STH 89 (West intersection), Town of Jefferson, Jefferson County

Crashes Summary (5 years, 2004-2008)

Table 16 2004 – 2008 Crash Summary at USH 18 @ STH 89 (West intersection)


Right Angle 1 1 4 6


Rear End 1 1

Sideswipe-Opposite

Sideswipe-Same 1 1

Merging

Head On 1 1

Hit Object

Run Off Road 1 1 2



Miscellaneous



There is a high number of right angle crashes at this intersection totaling 1 K, 1 B, 2 C, 8

PD. Six of the angle crashes happened with a northbound vehicle pulling out in front of an

25

eastbound vehicle. An improvement was done at this intersection in the past with the addition of

a separated right turn, which has help to reduce some crashes, however the separation is not to

current standards.


Reconstruct the separated right turn lane to match the one that is being place at the east

approach. It was felt that since the two intersections of 18 & 89 were so close to each other that

both intersections should be brought to the same standard.


The first row in Table 17 shows the evaluation results of individual countermeasure

based on SafetyAnalyst default parameters indicating a low Benefit-cost value primarily due to

the high CMF value of the countermeasure. The last row shows the SafetyAnalyst evaluation

result of the countermeasure based on parameter values provided in the PEF spreadsheets

associated with HSIP applications indicating a very low (0.31) Benefit-cost value to the PEF

value (1.38).


USH 18 @ STH 89 (West intersection)


CMF

Service

Life

Construction

Cost ($)

Cost

Effectiveness

($)

Cost

Effectiveness

EPDO ($)

Benefit

Cost

Ratio

Net

Benefit

($)

PEF

Increase length

of right-turn

lane

0.85 0.85 10 20,000 15,120 9,302 0.84 (3,293)

HSIP 0.65* 0.65* 10* 127,133* 41,191 25,343 0.31 (88,149) 1.38*


26

(h) USH 18 @ STH 89 (East intersection), Town of Jefferson, Jefferson County

Figure 12 USH 18 @ STH 89 (East intersection), Town of Jefferson, Jefferson County


Table 18 2003 – 2007 Crash Summary at USH 18 @ STH 89 (East intersection)


Right Angle 2 6 5 13


Rear End 1 1 1 3

Sideswipe-Opposite

Sideswipe-Same

Merging

Head On

Hit Object

Run Off Road



Miscellaneous 2 2



High number of right angle crashes at this intersection. Total of 1 A, 2B, 7 C, 8 PD.

Eleven of the angle crashes happened with a northbound vehicle pulling out in front of an

eastbound vehicle.


27

A separated right turn lane for eastbound traffic will be installed and the addition of a

splitter island on STH 89. Due to a building very close to the roadway, the roadway may need to

be moved to the north to accommodate the installation of the right turn lane.


The first three rows in Table 19 show the evaluation results of individual and combined

countermeasures based on SafetyAnalyst default parameters indicating moderate Benefit-cost

values primarily due to the high CMF values of the countermeasures. The last row shows the





USH 18 @ STH 89 (East intersection)


CMF

Service

Life

Construction

Cost ($)

Cost

Effectiveness

($)

Cost

Effectiveness

EPDO ($)

Benefit

Cost

Ratio

Net

Benefit

($)

PEF

Increase length

of right-turn

lane

0.85 0.85 10 20,000 10,296 5,510 1.37 7,386

Install right-turn

lane 0.86 0.77 20 50,000 15,812 6,515 1.16 4,531

CM above

combined 0.73 0.65 20 84,882 13,970 6,604 1.14 6,937

HSIP 0.68* 0.65* 10* 187,133* 45,626 23,280 0.32 (126,485) 1.39*


28

(i) STH 58 @ STH 82, City of Mauston, Juneau County

Figure 13 STH 58 @ STH 82, City of Mauston, Juneau County


Table 20 2004 – 2008 Crash Summary at STH 58 @ STH 82


Right Angle

3 1 7 11


Rear End

2 9 11

Sideswipe-Opposite

1 1

Sideswipe-Same

4 4

Merging

1 1

Head On

1 1

Hit Object

2 2

Run Off Road



Right Angle - Alcohol

Crash Totals

3 1 2 25 31


The typical rear end and sideswipe collisions are present at this signalized intersection.

The crashes with significant severity are a result of STH 58 vehicles, turning left onto STH 82,

29

failing to yield to northbound STH 58 traffic on green. This current left turn movement is

permissive on green.


The proposed project will increase the overall safety level of the intersection by

converting the permissive left turn from STH 58 onto STH 82 into a protected left turn,

upgrading the traffic signals to a monotube system, and installing a median on STH 82 past

Roosevelt St and the Walgreen’s entrance to restrict left turns.







(0.44) but very close Benefit-cost value to the PEF value (0.63).


STH 58 @ STH 82


CMF

Service

Life

Construction

Cost ($)

Cost

Effectiveness

($)

Cost

Effectiveness

EPDO ($)

Benefit

Cost

Ratio

Net

Benefit

($)

PEF

Provide

protected left-

turn phase

0.70 0.70 10 2,500 117 77 100.64 249,093

Install median

on major road to

restrict left-turn

maneuvers at

intersection

0.75 0.75 20 15,000 484 319 24.38 201,060

Convert signal

from pedestal-

mounted to

mast arm

0.51 0.56 20 130,000 2,138 1,461 5.32 322,121

CM above

combined 0.27 0.29 20 149,360 1,644 1,097 7.08 520,963

HSIP 0.60* 0.25* 10* 978,530* 34,522 17,506 0.44 (544,015) 0.63*


30

(j) USH 12 @ CTH HH/N, Town of Lyndon Station, Juneau County

Figure 14 USH 12 @ CTH HH/N, Town of Lyndon Station, Juneau County


Table 22 2003 – 2007 Crash Summary at USH 12 @ CTH HH/N


Right Angle

2 1 1 2 6


Rear End

Sideswipe-Opposite

2 2

Sideswipe-Same

Merging

Head On

Hit Object

Run Off Road



1 1

Misc.

Crash Totals

3 1 1 4 9


There has been a consistent angle crash problem at this intersection. It is talked about at

County Highway Safety meetings and has been brought to the attention of WisDOT many times

by the locals. All four quadrants of the intersection have buildings tight to the back of curb with

parked cars to the corner. Parking removal has been tried in the past but seems to always return.

31

A large overhead stop sign was installed in 2003, but hasn’t helped the crash problem, run

though crashes don’t appear to be the issue.


Curb corner bumpouts will be installed to physically remove the parking in these areas,

provide a refuge for pedestrians and create visual cue that a driver is approaching an intersection.

Install overhead Stop sign structure on northbound CTH HH.




value due to number of crashes, countermeasure costs, and CMF values. The last row shows the





USH 12 @ CTH HH/N


CMF

Service

Life

Construction

Cost ($)

Cost

Effectiveness

($)

Cost

Effectiveness

EPDO ($)

Benefit

Cost

Ratio

Net

Benefit

($)

PEF

Restrict parking

near intersection 0.51 0.51 10 4,000 623 451 16.73 62,924

Provide/increase

pedestrian

storage area

0.95 0.90 20 20,000 17,500 9,916 0.76 (2,749)

Install double

stop signs 0.89 0.90 10 500 347 257 29.29 14,146

CM above

combined 0.43 0.41 20 30,465 2,343 1,680 4.49 60,903

HSIP 0.72* 0.70* 10* 204,265* 55,018 39,159 0.19 (164,941) 1.05*


32

(k) USH 45 @ CTH B, Town of Neva, Langlade County

Figure 15 USH 45 @ CTH B, Town of Neva, Langlade County


Table 24 2003 – 2007 Crash Summary at USH 45 @ CTH B




Rear End

1 1 2

Sideswipe-Opposite

Sideswipe-Same

Merging

Head On

Hit Object

Run Off Road



Right Angle - Alcohol

1 1 2



It is believed that the angle of intersection in conjunction with the crossing vehicles

upright structural pillar support may be a major contributing factor in creating a blind spot for

vehicles crossing USH 45 from one side to the other. The crash data suggest that the CTH B

33

vehicles are misjudging the speed and location of the SB USH 45 traffic as they approach the

intersection.

• Severe WB CTH B through movement crashes with SB USH 45 traffic

• CTH B obtuse angle of intersection 107 degrees with USH 45

• ISD – Acceptable


The proposed improvement is to reconstruct the intersection such that CTH B intersects

USH 45 at 90 degrees and to install flashing beacons on CTH B to warn drivers of the

intersection.


The first five rows in Table 25 show the evaluation results of individual and combined


values primarily due to a mix of parameter values. The last row shows the SafetyAnalyst

evaluation result of combined countermeasures based on parameter values provided in the PEF

spreadsheets associated with HSIP applications indicating a very low (0.12) Benefit-cost value to

the PEF value (0.68).


USH 45 @ CTH B


CMF

Service

Life

Construction

Cost ($)

Cost

Effectiveness

($)

Cost

Effectiveness

EPDO ($)

Benefit

Cost

Ratio

Net

Benefit

($)

PEF

Change

streetscape to

increase

stimulation of

peripheral vision

0.90 0.90 10 6,000 3,375 2,583 2.83 11,003

Improve sight

distance to

intersection

0.90 0.90 5 3,000 3,143 2,405 3.04 11,415

Improve sight

triangles at

intersection

0.90 0.90 5 3,000 3,143 2,405 3.04 11,415

Install overhead

flashing beacon 0.70 0.70 20 20,000 2,150 1,645 4.45 39,542

CM above

combined 0.51 0.51 20 49,956 3,290 2,518 2.91 54,622

HSIP 0.68* 0.65* 10* 463,000* 82,243 61,414 0.12 (407,821) 0.68*


34

(l) USH 51 @ North Star Rd., Town of Merrill, Lincoln County

Figure 16 USH 51 @ North Star Rd., Town of Merrill, Lincoln County


Table 26 2004 – 2008 Crash Summary at USH 51 @ North Star Rd.


Right Angle

3 2 2 7


Rear End

1 1 2

Sideswipe-Opposite

Sideswipe-Same

1 1

Merging

1 1

Head On

Hit Object

Run Off Road

1 1



Miscellaneous

Crash Totals

3 2 4 3 12


It is believed that the angle of intersection in conjunction with the crossing vehicles

upright structural pillar support may be a contributing factor in creating a blind spot for vehicles

entering and or crossing USH 51 from one side to the other. The crash data also suggest that

North Star Road / CTH C vehicles may not have enough gap time to safely enter and or cross the

35

four lane divided highway of USH 51. The majority of the crashes occurred between May and

August.

It cannot be determined if vehicles are properly using the median as a refuge when

crossing USH 51 or if they are trying to cross the entire four lanes divided portion of USH 51 in

one movement. Only two of the crossover crashes allude to the fact that the driver indicated they

stopped at the crossover prior to completing their crossing maneuver. It should be noted that the

crossover refuges are not signed for a yield or stop control.


The proposed improvement is to construct an overpass of USH 51.




value due to mix of parameter values. The last row shows the SafetyAnalyst evaluation result of

combined countermeasures based on parameter values provided in the PEF spreadsheets

associated with HSIP applications indicating a very low (0.10) Benefit-cost value to the PEF

value (0.38).


USH 51 @ North Star Rd.


CMF

Service

Life

Construction

Cost ($)

Cost

Effectiveness

($)

Cost

Effectiveness

EPDO ($)

Benefit

Cost

Ratio

Net

Benefit

($)

PEF

Improve sight

distance to

intersection

0.90 0.90 5 3,000 2,518 1,758 4.16 17,681

Improve sight

triangles at

intersection

0.90 0.90 5 3,000 2,518 1,758 4.16 17,681

Install overhead

flashing beacon 0.70 0.70 20 20,000 1,722 1,202 6.09 58,338

CM above

combined 0.57 0.57 20 39,491 2,356 1,645 4.45 78,110

HSIP 0.08* 0.00* 10* 2,240,000* 109,604 74,586 0.10 (2,020,186) 0.38*


36

(l) STH 100 @ 51 St., City of Brown Deer, Milwaukee County

Figure 17 STH 100 @ 51 St., City of Brown Deer, Milwaukee County


Table 28 2004 – 2008 Crash Summary at STH 100 @ 51 St.


Right Angle 2 2 4

Left Turn - Main Road 3 4 8 4 19

Rear End 1 1 10 14 26

Sideswipe-Opposite

Sideswipe-Same 2 7 9

Merging

Head On

Hit Object

Run Off Road


Pedestrian Collisions 1 1

Miscellaneous



STH 100 is an East-West 6-lane divided highway with a posted speed limit of 40 mph.

Analysis has shown 38% of all intersection crashes are EB and WB rear ends and left turn

crashes. Much of this is due to a negative left turn lane alignment and poor signal visibility.

Currently the EB and WB left turns operate as protected-permitted. There has also been a

pedestrian collision. The current push button placement indicates a two stage crossing on STH

100, but the refuge is non-accessible.

37


To mitigate the LT crash problem, WisDOT proposes to construct the LT lanes to

provide channelization and a positive offset. With this the LT lanes will be lengthened and will

require the median openings be closed. This will improve the LT drivers’ vision of oncoming

traffic. Also, this will provide refuge for pedestrians making a two stage crossing across STH

100. Pedestrian countdown times will also be installed to improve pedestrian operation. To

mitigate the rear end crash issue, WisDOT proposes to upgrade traffic signals to provide

overhead signals above each lane to increase signal visibility.


The first six rows in Table 29 show the evaluation results of individual and combined

countermeasures based on SafetyAnalyst default parameters indicating very high Benefit-cost

values primarily due to the low cost estimates of the countermeasures. The last row shows the


provided in the PEF spreadsheets associated with HSIP applications indicating a low (0.66)



STH 100 @ 51 St., City of Brown Deer, Milwaukee County


CMF

Service

Life

Construction

Cost ($)

Cost

Effectiveness

($)

Cost

Effectiveness

EPDO ($)

Benefit

Cost

Ratio

Net

Benefit

($)

PEF

Increase length of

left-turn lane 0.85 0.85 10 60,000 3,451 1,827 4.26 195,562

Provide positive

offset of opposite

left-turn lanes

0.80 0.80 20 50,000 1,237 655 11.89 312,081

Install pedestrian

countdown signal

heads

0.98 0.98 10 3,000 1,294 685 11.36 31,075

Install raised median

at marked

crosswalks for use

as a pedestrian

refuge

1.00 0.29 20 30,000 462 156 49.83 839,963

Convert signal from

pedestal-mounted

to mast arm

0.51 0.56 20 130,000 1,312 730 10.66 720,234

CM above combined 0.34 0.11 20 319,878 2,397 1,090 7.14 1,126,443

HSIP 0.68* 0.64* 10* 868,000* 23,503 11,730 0.66 (292,013) 1.21*


38

(n) STH 16 @ STH 71, City of Sparta, Monroe County

Figure 18 STH 16 @ STH 71, City of Sparta, Monroe County


Table 30 2004 – 2007 Crash Summary at STH 16 @ STH 71




Rear End 1 1 2 3 7

Sideswipe-Opposite

Sideswipe-Same

Merging

Head On 1 1

Hit Object

Run Off Road



Miscellaneous 1 1



Total of 9 angle intersection crashes including 1 K 2 C and 7 PD. 7 rear end crashes

including 1 A, 1 B, 2 C & 5 PD crashes. Intersection is on a slight grade with the speed limit

39

changing from 40 to 55 just to the west. There is a Kwik Trip very close to the intersection that

creates additional safety issues with turning vehicles. This location was on the 5% report.


A roundabout is going to be installed at this intersection and an attempt to remove,

relocate or restrict the access in the area of the intersection.


The first row in Table 31 shows the evaluation results of roundabout installation based on

SafetyAnalyst default parameters indicating a moderate Benefit-cost value. The last row shows

the SafetyAnalyst evaluation result of combined countermeasures based on parameter values




STH 16 @ STH 71


CMF

Service

Life

Construction

Cost ($)

Cost

Effectiveness

($)

Cost

Effectiveness

EPDO ($)

Benefit

Cost

Ratio

Net

Benefit

($)

PEF

Install single-

lane roundabout 0.61 0.22 20 200,000 10,978 5,993 1.22 25,631

HSIP 0.26* 0.28* 10* 1,421,326* 71,288 50,735 0.14 (1,215,876) 0.57*


40

(o) STH 26 @ Plainview Dr./Washburn St., Town of Nekimi, Winnebago County

Figure 19 STH 26 @ Plainview Dr./Washburn St., Town of Nekimi, Winnebago County


Table 32 2005 – 2009 Crash Summary at STH 26 @ Plainview Dr./Washburn St.



Left Turn - Main Road 5 2 8 15

Rear End 6 27 33

Sideswipe-Opposite

Sideswipe-Same 1 1 2

Merging

Head On

Hit Object 1 1

Run Off Road



Miscellaneous 1 1 2



41

The intersections at the ramps are currently stop controlled at the ramp exit. The

predominant crash type occurring at the ramp intersections are right angle and rear end crashes.

A signal warrant analysis was completed in 2006 and concluded signals at the ramp terminals at

USH 41 and STH 26 would be warranted by 2013.

The intersection of STH 26 & Washburn is the southernmost interchange serving the

Oshkosh area. STH 26 also serves as the shortcut between the Fox Cities and Madison. The

intersection is located approximately 600’ from the US 41 interchange with STH 26. The cross

section on STH 26 includes two through lanes in each direction and left and right turn lanes. A

large truck stop exists on the south side of the intersection. Immediately east of the intersection a

crest vertical curve exits as STH 26 passes over US 41. The predominant crash type is right angle

and left turn crashes.


The proposed improvement will install traffic signals at the ramp terminals and at the

intersection of STH 26 and Washburn Street.


The first row in Table 33 shows the evaluation results of individual countermeasure

based on SafetyAnalyst default parameters indicating a moderate Benefit-cost value primarily

due to the low cost estimates of the countermeasure. The last row shows the SafetyAnalyst

evaluation result of combined countermeasures based on parameter values provided in the PEF

spreadsheets associated with HSIP applications indicating a low (0.88) Benefit-cost value to the

PEF value (1.39).


STH 26 @ Plainview Dr./Washburn St.


CMF

Service

Life

Construction

Cost ($)

Cost

Effectiveness

($)

Cost

Effectiveness

EPDO ($)

Benefit

Cost

Ratio

Net

Benefit

($)

PEF

Install traffic

control signals, if

warranted

0.77 0.77 10 300,000 9,650 5,918 1.31 94,024

HSIP 0.73* 0.60* 10* 625,591* 16,934 8,807 0.88 (73,478) 1.39*


42

(p) STH 162 (H Hunt Rd. to Kammel Rd.), Town of Washington, La Crosse County

Figure 20 STH 162 (H Hunt Rd. to Kammel Rd.), Town of Washington, La Crosse County


Table 34 2003 – 2007 Crash Summary at STH 162 (H Hunt Rd. to Kammel Rd.)


Right Angle


Rear End

Sideswipe-Opposite

Sideswipe-Same

Merging

Head On 1 1

Hit Object

Run Off Road 1 1

Fail to Negotiate Curve 2 1 1 4


Miscellaneous 1 1



43

A high number of run off the road were reported at this location and vehicles failed to

negotiate curve crashes through a section of sharp curves resulting in 3 A injury, 1 B, 2 C and 2

PD crashes.


The proposed construction would realign the roadway and flatten out the curves to bring

them up to standards. Also new marking and signing would also be placed on the road section.




value for various reasons. The last row shows the SafetyAnalyst evaluation result of combined

countermeasures based on parameter values provided in the PEF spreadsheets associated with

HSIP applications indicating a very low (0.10) Benefit-cost value to the PEF value (0.50).


STH 162 (H Hunt Rd. to Kammel Rd.)


CMF

Service

Life

Construction

Cost ($)

Cost

Effectiveness

($)

Cost

Effectiveness

EPDO ($)

Benefit

Cost

Ratio

Net

Benefit

($)

PEF

Flatten crest

vertical curve 0.80 0.50 20 700,000 226,852 56,978 0.13 (349,523)

Flatten

horizontal curve 0.49 0.49 20 700,000 89,383 40,766 0.18 (328,911)

Install edgelines,

centerlines, and

post mounted

delineators

0.90 0.55 3 3,000 6,114 1,453 5.06 36,773

Install curve

ahead warning

signs

0.90 0.90 10 500 565 258 28.54 13,772

CM above

combined 0.32 0.12 20 1,416,651 134,847 53,132 0.14 (699,767)

HSIP 0.23* 0.13* 10* 1,165,530* 170,160 72,719 0.10 (1,047,594) 0.50*


44

(q) STH 60 (West of Gotham), Town of Orion, Richland County

Figure 21 STH 60 (West of Gotham), Town of Orion, Richland County


Table 36 2003 – 2007 Crash Summary at STH 60 (West of Gotham)


Right Angle


Rear End

Sideswipe-Opposite

Sideswipe-Same

Merging

Head On

Hit Object

Run Off Road 2 2 3 6 13

Fail to Negotiate Curve 2 1 4 7


Miscellaneous



A high number of run off the road and fail to negotiate curve crashes through a section of

sharp curves resulting in 3 A injury, 1 B, 3 C and 10 PD crashes.


45

The proposed construction would realign the roadway and flatten out the curves to bring

them up to standards and also include new marking and signing.




values for various reasons. The last row shows the SafetyAnalyst evaluation result of combined

countermeasures based on parameter values provided in the PEF spreadsheets associated with

HSIP applications indicating very low (0.40) Benefit-cost value to the PEF value (1.05).


STH 60 (West of Gotham)


CMF

Service

Life

Construction

Cost ($)

Cost

Effectiveness

($)

Cost

Effectiveness

EPDO ($)

Benefit

Cost

Ratio

Net

Benefit

($)

PEF

Flatten crest

vertical curve 0.80 0.50 20 700,000 62,939 18,055 0.41 (237,783)

Flatten

horizontal curve 0.85 0.85 20 700,000 81,658 40,944 0.18 (329,225)

Install edgelines,

centerlines, and

post mounted

delineators

0.90 0.55 3 5,350 3,628 862 8.54 121,572

Install

combination

curve ahead

warning and

advisory speed

signs

0.87 0.87 10 500 121 60 121.66 60,328

CM above

combined 0.53 0.20 20 1,429,011 54,656 20,341 0.36 (522,952)

HSIP 0.13* 0.13* 10* 1,005,530* 36,249 18,175 0.40 (598,447) 1.05*


46

V. CONCLUSIONS AND RECOMMENDATIONS

The comparison of SafetyAnalyst evaluation results with PEF values using SafetyAnalyst

provided parameters and parameters from HSIP project application forms (as shown in last row

of each result tables in previous section) shows that in all the cases, the benefit-cost ratio

calculated by SafetyAnalyst is smaller than the PEF factor calculated by the PEF Tool (Also

shown in the last row in the result tables). This means that given same site, crash history,

countermeasure cost, service life, and analysis period, PEF is more optimistic than SafetyAnalyst

in the effectiveness of a countermeasure. The major reason behind this is:

• SafetyAnalyst utilizes the Empirical Bayes (EB) method in the effective analysis, but the

PEF Tool does not. This means SafetyAnalyst tends to expect smaller crash reduction

because of the regression-to-the-mean (RTM) effect, but the PEF Tool does not consider

this effect. This difference can be especially large for the more significant sites, that is,

those sites with worse crash histories. The HSIP sites happen to belong to these sites.

It should be noted that for most of the projects, the benefit-cost ratio of the combined

countermeasures recommended by SafetyAnalyst tends to be larger than that of the

countermeasure proposed in the original HSIP application (as shown in the B/C ratios of the last

two rows in the result tables). There are several reasons behind this:

• The default expected cost of the countermeasures in the SafetyAnalyst library is much

lower than the expected cost in the HSIP applications.

• SafetyAnalyst expects many countermeasures have 20 years of service life, but the

original HSIP application expect 10 years of service life for all the countermeasures.

The results in the previous sections also show that except for six projects, the Benefit-

cost values conformed with the PEF value based on parameters from the HSIP applications. This

indicates that the procedures and methods used in SafetyAnalyst are well suited for project

evaluations and far superior than PEF due to the use of Empirical Bayes method. The results of

evaluation of individual and combined, proposed countermeasures using SafetyAnalyst also

provides great flexibility and options in analyzing different options and avenues, quickly and

efficiently. Although there is difference between the results of SafetyAnalyst and PEF

evaluation, SafetyAnalyst analysis is superior for several reasons described below.

Advantages of SafetyAnalyst

• SafetyAnalyst uses state of the art Empirical Bayes methods to provide accurate estimates

of safety benefits.

• SafetyAnalyst provides greater flexibility, speed, and efficiency in identifying and

comparison different countermeasures against each other or their combined effect for best

use of available resources.

• The economic analysis procedures are recognized in the Highway Safety Manual.

47

• SafetyAnalyst streamlines the whole process of site screening, diagnosis, and economic

analysis. Because the process is standardized, it is prone to fewer errors.

• SafetyAnalyst includes almost all the parameters used for PEF. In addition, it provides the

flexibility of customizing many more parameters, including countermeasure service life,

analysis period, etc.

• Multiple economic appraisal approaches can be applied.

• Can be used for economic evaluation of a single site or multiple sites.

However, SafetyAnalyst also has certain shortcomings.

Shortcomings of SafetyAnalyst

• The current default cost estimates in SafetyAnalyst are much lower than estimates

provided in the HSIP applications for various countermeasures. It is recommended that a

generalized list of acceptable costs per countermeasure be developed to be used during

the implementation of SafetyAnalyst.

• In the PEF Tool, different AMFs can be used for different crash types, but only one value

can be used in SafetyAnalyst. The analyst has to calculate the overall AMF manually.

• SafetyAnalyst doesn’t have place to input project maintenance cost. The cost has to be

converted to present value by the analyst manually.

Summary

The results of SafetyAnalyst evaluation are dependent upon the availability and quality of

data which is no different from the requirements of PEF. Overall, SafetyAnalyst provides

excellent and diversified results to evaluate proposed countermeasures for projects. The analyst

is provided with many options and choices to comprehensively analyze proposed

countermeasures and select the best options. Crucially, SafetyAnalyst can also be used for the

evaluation of HSIP projects once they have been completed which is an added advantage of

using SafetyAnalyst.

1

APPENDIX A – SafetyAnalyst Data Elements Availability Assessment by Wisconsin Department of Transportation (WisDOT)

Variable

Gen

eral

Mo

du

le 1

Mo

du

le 2

Mo

du

le 3

Mo

du

le 4

Ma

nd

ato

ry

Needed for

Specific

Program

Features

Ma

nd

ato

ry

Needed

for

Specific

Program

Features

Ma

nd

ato

ry

Needed

for

Specific

Program

Features

Ma

nd

ato

ry

Needed

for

Specific

Counterm

easures

Ma

nd

ato

ry

Needed

for

Specific

Program

Features

E. NOT AT DOT!! Roadway Segment Inventory Data

E.1 Segment-Level Elements

E.1.1 Segment Number x x x x x

E.1.2 Route Type xa

E.1.3 Route Name/Number xa

E.1.4 Alternate Route Numbers

E.1.5 Route Number Display Value (derived) x x x x x

E.1.6 Major Road Name

E.1.7 County Number xa

E.1.8 Roadway Segment Locationb x x x x x

E.1.9 Highway System Code xa

E.1.10 FWY ONLY Begin Milepost Display Value (derived) xa x x x x

E.1.11 Segment Length x x x x x

E.1.12 District Number

E.1.13 City/Town Number

E.1.14 Jurisdiction x

E.1.15 Area Type x x x x x

E.1.16 NO Terrain x

E.1.17 Roadway Class Level 1 x

E.1.18 Roadway Class Level 2 (derived)

E.1.19 Roadway Class Level 3 (derived) x x x x x

E.1.20 Number of Through Lanes - Dir 1 x x x x

E.1.21 Number of Through Lanes - Dir 2 x x x x

E.1.22 Number of Through Lanes (derived) x x x x x

E.1.23 Auxiliary Lanes - Dir 1 x x

E.1.24 Auxiliary Lanes - Dir 2 x x

E.1.25 Lane Width x x

E.1.26 Median Type Level 1 x x x x x

E.1.27 Median Type Level 2 (derived) x x x x x

E.1.28 Median Width

E.1.29 Shoulder Type x x

E.1.30 Shoulder Width x x

E.1.31 Varies Access Control x x x x x

E.1.32 Commercial Only Driveway Density x x

E.1.33 Average Annual Daily Traffic x x x x x

E.1.34 Growth Factor x x x

E.1.35 Percent Heavy Vehicles

E.1.36 100TH HOUR Peak or Design Hourly Volume

E.1.37 Posted Speed Limit

E.1.38 Two-way vs. One-way Operation x x x x x

E.1.39 Direction of Travel x x

E.1.40 FWY ONLY Direction of Increasing Mileposts x x

2

E.1.41 NO Bikeway - Dir 1

E.1.42 NO Bikeway - Dir 2

E.1.43 Interchange Influence Area - Mainline x x x x x

E.1.44 NO Date Opened to Traffic x

E.1.45 ? Discontinuity x x

E.1.46 ? Corridor Number x x

F. Intersection Inventory Data

F.1 Overall Intersection Data

F.1.1 NO Intersection Number x x x x x

F.1.2 Route Type xa

F.1.3 Route Name/Number xa

F.1.4 Alternate Route Numbers

F.1.5 Route Number Display Value (derived) x x x x x

F.1.6 County Number xa

F.1.7 Intersection Locationb x x x x x

F.1.8 Milepost Display Value (derived) xa x x x x

F.1.9 Highway System Code xa

F.1.10 Major Road Name x x

F.1.11 Minor Road Name x x

F.1.12 Major Road Direction x x

F.1.13 Minor Road Location Identifier x x x x x

F.1.14 Beginning Influence Zone xc

F.1.15 End Influence Zone xc

F.1.16 District Number

F.1.17 City/Town Number

F.1.18 Jurisdiction x

F.1.19 Area Type x x x x x

F.1.20

Available for partial (3 quarters) state highway

intersections Intersection Type Level 1 x x x x x

F.1.21


intersections Intersection Type Level 2 (derived) x x

F.1.22


intersections Traffic Control Type at Intersection Level 1 x x x x x

F.1.23


intersections Traffic Control Type at Intersection Level 2 (derived)

F.1.24


intersections Traffic Control Type at Intersection Level 3 (derived)

F.1.25 NO Offset Intersection

F.1.26 NO Offset Distance

F.1.27 Major Road AADT (derived) x x x x x

F.1.28 NO, unless State Truck

Intersections Minor Road AADT (derived) x x x x x

F.1.29 Growth Factor x x

F.1.30 NO Date Opened to Traffic x

F.1.31 NO Corridor Number x x

F.2 Data for Each Intersection Leg

F.2.1 Partial Intersection Leg x x x x x

F.2.2 NO Direction of Intersection Leg x x

F.2.3 Number of Through Lanes x x

F.2.4 Number of Left-turn Lanes

F.2.5 Number of Right-turn Lanes

F.2.6 Median Type

F.2.7 Average Annual Daily Traffic x x x x x

3

F.2.8 Data available for few

intersections Vehicle Movements by Daily Volume

F.2.9 Data available for few

intersections Vehicle Movements by Hourly Volume

F.2.10

Left-turn lane is available for partial state highway

intersections Left-turn Phasing

F.2.11 Posted Speed Limit

F.2.12 NO Turn Prohibitions

F.2.13 Two-way vs. One-way Operation

G.1 Ramp Inventory Data

G.1.1 NO Ramp Number x x x x x

G.1.2 Route Type xa

G.1.3 Route Name or Number xa

G.1.4 Alternate Route Numbers

G.1.5 Route Number Display Value (derived) x x x x x

G.1.6 Major Road Name

G.1.7 County Number xa

G.1.8 Ramp Locationb x x x x x

G.1.9 Milepost Display Value (derived) xa x x x x

G.1.10 Highway System Code xa

G.1.11 NO Ramp Description

G.1.12 District Number

G.1.13 City/Town Number

G.1.14 Jurisdiction x

G.1.15 Area Type x x x x x

G.1.16 NO Ramp Type x x x x x

G.1.17 NO Ramp Configuration x x x x x

G.1.18 ? Type of Connection (at Freeway)

G.1.19 ? Type of Connection (at Crossroad)

G.1.20 Ramp Number of Lanes x x

G.1.21 Ramp Length x x x x x

G.1.22 ATR data Ramp Average Annual Daily Traffic x x x x x

G.1.23 ATR data Growth Factor x x

G.1.24 NO Date Opened to Traffic x

G.1.25 NO Corridor Number x x

Note: Variable numbers refer to the data dictionary in the SafetyAnalyst User's Manual, Appendices E through H

a - Mandatory if needed for the particular location reference system being used

b - Any variables needed to define the particular location in the location reference system being used are mandatory c - An influence zone of 0.05 mi on either side of the intersection (or half the distance to the next intersection) is assumed by default unless a different influence zone is

defined by variables F.1.14 and F.1.15

Wisconsin has the information but necessary the same data format

Wisconsin has similar or derivable information

Wisconsin does not have such information

1

APPENDIX B

SAFETYANALYST DATA IMPORT PROCESS STEPS

The data process includes generation of CSV files by Brad from WisDOT data which are loaded

into Oracle to create a dataset called SALDR. Now we will use SALDR dataset and create a

mapping schema in the Data Management Tool of SA to import the data from SALDR into

SAPRD which will be useable by SA.

SafetyAnalyst Data Schema Mapping Process

1. Open the SA Data Management Tool and the following screen shows up. Provide a new

name in the “Data Set Attributes” tab which will be the name of the dataset that will be

imported into SA.

2. Click on the “Database Attributes” tab and following screenshot will show up. N Fill up

the values as shown below. These are the details of the attributes of the database SALDR

2

which is being hosted by the server defined below. By defining these attributes, we will

be able to access that database through SA.

3. Click on the “Import” tab and the following screen would show up. The “Import Map”

area shows two list boxes. The first list box shows the mapping schema currently

selected and choice for user to select other mapping schema already defined. The list box

on the right lets the user create, edit, and manage mapping schemas.

4. As shown below, “LDR to PRD” is a mapping schema already created. Click on

“Manage Import Maps” and the following window shows up where this schema can be

edited.

3

5. Click on “Edit” in the smaller “Manage Import Maps” window and the following window

will show up showing the “Edit Import Map” area. It shows the list of the import map

data elements and their status in terms of whether they have been defined or not yet (Note

the difference between the Accident data sign and others).

4

6. 6. Click on the “Source Databases” to show the following window to define a source

database where SALDR data resides. Here we can define a new source database or edit a

current one. Click on “loader tables” and click edit which shows the database which has

already been defined and corresponds to SALDR tables shown in the following window.

5

7. The above window shows the attributes of the “Source Database” which is SALDR. The

details show the database type (Oracle), host address, port, username and password to

access the source database. NOTE: the username and password corresponds to SAPRD

which is the destination database not SALDR.

8. Once the “Source Database” has been defined correctly, we can proceed with actual

mapping process. Come back to this window and click on “Accident” in the left area and

expand it. This shows details of data type “Accident” with data elements to be defined,

and other details such as:

- Default Database: loader tables (SAPRD destination database)

- Default Table Name: saldr.dataset_accident (SALDR source database)

- Key Column Name: accidentid (The name of Accident ID data element in the SALDR

tables, names of other elements can be found in Steven’s email or through SQLite).

6

9. Click on “Accident ID” and the following window will show up which shows whether

the data is available in the agency’s dataset or not and whether the data element is

mandatory or not. The “Column Name or Expression” here will define the name of this

particular data element as in the agency’s dataset (this name will come from files in

Steven’s email or by accessing the Oracle database through SQLlite).

Bill et al., 2011

Documents

Transcript of Bill et al., 2011