INTERCHANGE OPERATIONAL ANALYSIS REPORT (IOAR) · 2020. 3. 20. · wrong-way movements on ramps,...

INTERCHANGE

OPERATIONAL ANALYSIS

REPORT (IOAR)

I-75 at SR 26 (Newberry Road)

Alachua County, Florida

FPID: 437354-1

April 2018 Updated July 2018

INTERCHANGE OPERATIONAL ANALYSIS REPORT

(IOAR)

I-75 at SR 26 (Newberry Road)

FPID: 437354-1

Prepared for:

Florida Department of Transportation - District Two

Alachua County, Florida

April 2018 Updated July 2018

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437354-1

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EXECUTIVE SUMMARY I-75 at SR 26 IOAR

EXECUTIVE SUMMARY

The purpose of this study is to determine what short term enhancements can be programmed to

improve traffic operations at the I-75/SR 26 (Newberry Road) interchange. Short term

improvements are aimed at increasing the efficiency of the SR 26 intersections while minimizing

or eliminating right-of-way and bridge impacts.

The primary need for this project is to alleviate existing and future traffic congestion and delay at

the study intersections. If no improvements are made to the ramp terminal intersections and

adjacent intersections, traffic operations within the study area will continue to deteriorate as

traffic continues to grow.

The existing traffic for this Interchange Operational Analysis Report (IOAR) is based on the

Safety Study prepared in October of 2014 by the Florida Department of Transportation (FDOT),

District 2 Traffic Operations Office. The primary basis for the growth rate development, used to

develop the traffic projections in this IOAR, are the historical counts from the 2016 Florida

Traffic Information (FTI) DVD, the latest version of the Gainesville Metropolitan Transportation

Planning Organization (MTPO) Model and Relief Study Model (RSM) developed for the recent

North I-75 Master Plan. The analysis years for this study include Existing Year 2018, Opening

Year 2019 and Design Year 2029. The operational analysis for this study was performed using

the latest version of Synchro and Synchro based results have been reported for all intersections.

Two alternatives were evaluated to address the purpose and needs identified for this project.

These include the No-Build Alternative and the Build Alternative. The Build Alternative, based

on recommendations of the Safety Study, implements improvements to all the study intersections

along SR 26.

SR 26 at I-75 Southbound Ramps

• Westbound direction: provide two left turn lanes

• Northbound direction: provide two right turn lanes and convert the through lane to a

shared through/left turn lane

SR 26 at I-75 Northbound On-Ramp

• Eastbound direction: provide two left turn lanes

• Westbound direction: convert shared through/right turn lane to through lane and add one

right turn lane

SR 26 at NW 69th Terrace

• Eastbound direction: provide two left turn lanes

Based on the evaluations of the No-Build and Build Alternatives, the recommended alternative,

for approval in this study, is the Build Alternative. However by the Design Year 2029, the


proposed improvements will not provide acceptable level of service (LOS) at the study

intersections. So, it is recommended that ultimate improvements be analyzed to address future

traffic growth in the study area.

This IOAR has been developed in accordance with the FDOT Policy No. 000-525-015: Approval

of New or Modified Access to Highways on the Strategic Intermodal System (SIS), FDOT

Procedure No. 525-030-160: Approval of New or Modified interchange access to limited access

facilities on SIS, Interchange Access Request User’s Guide (IARUG), and the FDOT Traffic

Forecasting Handbook (Procedure No. 525-030-120).

Compliance with FHWA General Requirements

The following requirements serve as the primary decision criteria used in approval of

interchange access requests. Responses to each of the Federal Highway Administration (FHWA)

two policy points are provided to show that the proposed modification for the I-75 at SR 26

interchange is viable based on the conceptual analysis performed to date.

FHWA Policy Point 1

An operational and safety analysis has concluded that the proposed change in access does not

have a significant adverse impact on the safety and operation of the Interstate facility (which

includes mainline lanes, existing, new, or modified ramps, ramp intersections with crossroad) or

on the local street network based on both the current and the planned future traffic projections.

The analysis should, particularly in urbanized areas, include at least the first adjacent existing

or proposed interchange on either side of the proposed change in access (23 CFR 625.2(a),

655.603(d) and 771.111(f)). The crossroads and the local street network, to at least the first

major intersection on either side of the proposed change in access, should be included in this

analysis to the extent necessary to fully evaluate the safety and operational impacts that the

proposed change in access and other transportation improvements may have on the local street

network (23 CFR 625.2(a) and 655.603(d)). Requests for a proposed change in access should

include a description and assessment of the impacts and ability of the proposed changes to safely

and efficiently collect distribute, and accommodate traffic on the Interstate facility, ramps,

intersection of ramps with crossroad, and local street network (23 CFR 625.2(a) and

655.603(d)). Each request should also include a conceptual plan of the type and location of the

signs proposed to support each design alternative (23 U.S.C. 109(d) and 23 CFR 655.603(d)).

An in‐depth operational and safety analysis was conducted to study the impacts of the proposed

improvements at the I-75/SR 26 interchange. Several performance measures were used to

compare the operations of the existing system under No-Build and Build conditions. Key

measures included delay, Level of Service (LOS) and 95th Percentile Queues for existing and

proposed conditions.

Operational analysis conducted for the short term improvements confirm that the proposed

modifications are not expected to have significant adverse impacts on safety or operations at the


I-75/SR 26 interchange and adjacent intersections. When compared to the No-Build Alternative,

the proposed short term improvements will provide up to a 61% reduction in delay at the study

intersections, and will provide up to a 73% reduction in queuing at the study intersections in the

Design Year 2029.

The short term improvements at the study intersections are, also, expected to reduce the number

of collisions at the study intersections, and not have an adverse impact on safety. Using Crash

Modification Factors (CMFs) from the CMF Clearinghouse, a predicted number of crashes was

calculated after the implementation of the improvements. Based on the application of the CMFs

to the study intersections, a 12% reduction in crashes is expected.

The I-75 at SR 26 IOAR will not involve any new mainline access points or change in the

current access locations. The proposed short term improvements are only being applied to the

study intersections. Hence, no analysis was performed for the I-75 mainline, I-75 ramps or

adjacent ramps. Also, the existing signing plan along I-75 and SR 26 will be adequate for the

proposed improvements. A new conceptual signing plan is not required for these improvements.

FHWA Policy Point 2

The proposed access connects to a public road only and will provide for all traffic movements.

Less than “full interchanges” may be considered on a case-by-case basis for applications

requiring special access, such as managed lanes (e.g., transit, HOVs, HOT lanes) or park and

ride lots. The proposed access will be designed to meet or exceed current standards (23 CFR

625.2(a), 625.4(a)(2), and 655.603(d)). In rare instances where all basic movements are not

provided by the proposed design, the report should include a full-interchange option with a

comparison of the operational and safety analyses to the partial-interchange option. The report

should also include the mitigation proposed to compensate for the missing movements, including

wayfinding signage, impacts on local intersections, mitigation of driver expectation leading to

wrong-way movements on ramps, etc. The report should describe whether future provision of a

full interchange is precluded by the proposed design.

The proposed short term improvements to the I-75 at SR 26 interchange and adjacent

intersections will provide full access and cater to all traffic movements from SR 26 to and from

I-75. The proposed modifications are designed to meet current standards for federal-aid projects

on the interstate system and conform to American Association of State Highway and

Transportation Officials (AASHTO) and the FDOT design standards.

TABLE OF CONTENTS I-75 at SR 26 IOAR

Table of Contents

1. INTRODUCTION................................................................................................................. 1

1.1. BACKGROUND ............................................................................................................................................. 1

1.2. PURPOSE AND NEED .................................................................................................................................... 1

1.3. PROJECT LOCATION ..................................................................................................................................... 1

2. METHODOLOGY ............................................................................................................... 3

2.1. AREA OF INFLUENCE ................................................................................................................................... 3

2.2. ANALYSIS YEARS ........................................................................................................................................ 3

2.3. DATA COLLECTION AND SOURCES .............................................................................................................. 3

2.4. TRAVEL DEMAND FORECASTING................................................................................................................. 4

2.5. OPERATIONAL ANALYSIS PROCEDURES ...................................................................................................... 4

2.6. LOS CRITERIA ............................................................................................................................................ 4

3. EXISTING CONDITIONS .................................................................................................. 5

3.1. TYPICAL SECTIONS ...................................................................................................................................... 5

3.2. STUDY INTERCHANGE ................................................................................................................................. 5

3.3. INTERSECTION GEOMETRY .......................................................................................................................... 6

3.4. EXISTING OPERATIONAL PERFORMANCE..................................................................................................... 7

4. NEED ................................................................................................................................... 21

5. FUTURE NO-BUILD CONDITIONS .............................................................................. 22

5.1. FUTURE TRAFFIC FORECAST ..................................................................................................................... 22

5.2. OPERATIONAL ANALYSIS .......................................................................................................................... 23

6. BUILD CONDITIONS ....................................................................................................... 33

6.1. BUILD ALTERNATIVE ................................................................................................................................ 33

6.2. OPERATIONAL ANALYSIS .......................................................................................................................... 34

6.3. PREDICTIVE SAFETY ANALYSIS ................................................................................................................. 43

7. EVALUATON OF ALTERNATIVES .............................................................................. 44

7.1. COMPLIANCE WITH POLICIES AND ENGINEERING STANDARDS .................................................................. 44

7.2. ALTERNATIVES COMPARISON ................................................................................................................... 44

7.3. DESIGN EXCEPTIONS AND VARIATIONS ..................................................................................................... 45

7.4. SUMMARY AND RECOMMENDATIONS ........................................................................................................ 45

8. JUSTIFICATION ............................................................................................................... 46

8.1. COMPLIANCE WITH FHWA GENERAL REQUIREMENTS ............................................................................. 46

9. CONCEPTUAL FUNDING PLAN/CONSTRUCTION SCHEDULE .......................... 48


List of Figures Figure 1-1: Project Location and Area of Influence Map ............................................................... 2

Figure 3-1: I-75 at SR 26 Existing Layout...................................................................................... 5

Figure 3-2: Existing Lane Configuration ...................................................................................... 11

Figure 3-3: Existing Year 2018 Peak Hour Volumes and LOS .................................................... 12

Figure 3-4: SR 26 at NW 75th Street Crash Types (2012-2016) ................................................... 14

Figure 3-5: SR 26 at Southbound Ramps Crash Types (2012-2016) ........................................... 15

Figure 3-6: SR 26 at Northbound Off-Ramp Crash Types (2012-2016) ...................................... 16

Figure 3-7: SR 26 at Northbound On-Ramp Crash Types (2012-2016) ....................................... 18

Figure 3-8: SR 26 at NW 69th Terrace Crash Types (2012-2016) ................................................ 19

Figure 5-1: No-Build Lane Configuration .................................................................................... 30

Figure 5-2: Opening Year 2019 No-Build Peak Hour Volumes and LOS ................................... 31

Figure 5-3: Design Year 2029 No-Build Peak Hour Volumes and LOS ...................................... 32

Figure 6-1: Build Lane Configuration .......................................................................................... 40

Figure 6-2: Opening Year 2019 Build Peak Hour Volumes and LOS ......................................... 41

Figure 6-3: Design Year 2029 Build Peak Hour Volumes and LOS ............................................ 42

List of Tables Table 3-1: Existing Year 2018 Intersection Analysis Results ........................................................ 7

Table 3-2: Existing Year 2018 Signals Queuing Analysis Results .............................................. 10

Table 3-3: SR 26 at NW 75th Street Severity Summary (2012-2016) .......................................... 14

Table 3-4: SR 26 at Southbound Ramps Severity Summary (2012-2016) ................................... 15

Table 3-5: SR 26 at Northbound Off-Ramp Severity Summary (2012-2016) ............................. 17

Table 3-6: SR 26 at Northbound On-Ramp Severity Summary (2012-2016) .............................. 18

Table 3-7: SR 26 at NW 69th Terrace Severity Summary (2012-2016) ....................................... 19

Table 3-8: Study Intersection Crash Summary (2012-2016) ........................................................ 20

Table 5-1: FTI Historic Counts Growth Rate ............................................................................... 22

Table 5-2: Gainesville MTPO Model Growth Rate ...................................................................... 23

Table 5-3: RSM Growth Rate ....................................................................................................... 23

Table 5-4: Opening Year 2019 No-Build Intersection Analysis Results ........................................ 24

Table 5-5: Design Year 2029 No-Build Intersection Analysis Results ....................................... 25

Table 5-6: Opening Year 2019 No-Build Signals Queuing Analysis Results ............................. 27

Table 5-7: Design Year 2029 No-Build Signals Queuing Analysis Results ............................... 29

Table 6-1: Opening Year 2019 Build Intersection Analysis Results .............................................. 34

Table 6-2: Design Year 2029 Build Intersection Analysis Results ............................................. 35

Table 6-3: Opening Year 2019 Build Signals Queuing Analysis Results ................................... 37

Table 6-4: Design Year 2029 Build Signals Queuing Analysis Results ...................................... 39

Table 6-5: Reduction in Crashes .................................................................................................. 43

Table 7-1: Design Year 2029 No-Build and Build Alternatives Intersections Comparison........ 44


List of Appendices

Appendix A: FDOT Safety Study for SR 26 from NW 75th Street to NW 69th Terrace

Appendix B: Existing Year 2018 Alternative Synchro Operational Analysis

Appendix C: Raw Crash Data

Appendix D: 2019 and 2029 No-Build Alternative Synchro Operational Analysis

Appendix E: 2019 and 2029 Build Alternative Synchro Operational Analysis

Appendix F: Build Concept Figure

1.0 INTRODUCTION I-75 at SR 26 IOAR

1

1. INTRODUCTION

1.1. Background The Florida Department of Transportation (FDOT) District Two is requesting approval for the

short term improvements to the I-75 at SR 26 interchange located within the City of Gainesville

in Alachua County. I-75 is a major north-south interstate in the state of Florida. I-75 is a major

commuter, tourist and trucking roadway that results in heavy passenger vehicle and truck traffic

on a daily occurrence. SR 26 (Newberry Road) is a major corridor with many retail, residential

and commercial properties adjacent to it such as the Oaks Mall.

This IOAR has been developed in accordance with the FDOT Policy No. 000-525-015: Approval

of New or Modified Access to Highways on the Strategic Intermodal System (SIS), FDOT

Procedure No. 525-030-160: Approval of New or Modified interchange access to limited access

facilities on SIS, Interchange Access Request User’s Guide (IARUG), and the FDOT Traffic

Forecasting Handbook (Procedure No. 525-030-120).

1.2. Purpose and Need The purpose of this study is to determine what short term enhancements can be programmed to

improve traffic operations, reduce congestion and improve safety at the ramp terminal

intersection and adjacent intersections. Short term improvements are aimed at increasing the

efficiency of the SR 26 intersections while minimizing or eliminating right-of-way and bridge

impacts. A Safety Study was completed by FDOT District 2 Traffic Operations Office in

October 2014 for the study interchange and adjacent intersections. The Safety Study identified

deficiencies at the intersections and recommended improvements aimed at improving operations

and safety.

The primary needs for this project is to improve safety and alleviate existing and future traffic

congestion and delay at the study intersections. If no improvements are made to the ramp

terminal intersections and adjacent intersections, traffic operations within the study area will

continue to deteriorate as traffic continues to grow.

1.3. Project Location The subject interchange is located in Alachua County along I-75 at Milepost 14.5, Section

number 26260000. The I-75 at SR 26 interchange is located between the I-75 at SR 24

interchange to the south and I-75 at SR 222 interchange to the north. The project location and the

study area are shown in Figure 1-1. The study area includes the following interchanges (as

shown in Figure 1-1):

STUDY INTERCHANGE: I-75 at SR 26

!!

!!

!

±

Legend! Study Intersections

Influence Area0 0.07 0.14 0.210.035 Miles

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I-75 at SR 26 (Newberry Road) IOAR

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Project Location and Study Area Map

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Figure 1-1

2.0 METHODOLOGY I-75 at SR 26 IOAR

3

2. METHODOLOGY

2.1. Area of Influence

The subject interchange is located in Alachua County’s urbanized area. The following major

interchange has been analyzed.

I-75 at SR 26 is located at milepost 14.5 (Section No. 26260000). I-75 is an Urban

Principal Arterial-Interstate and therefore this interchange is in an urbanized area.

The major study corridor is SR 26:

SR 26 is 5 lanes west of I-75 (3 lanes eastbound and 2 lanes westbound) and 6 lanes east

of I-75. SR 26 is a divided Urban Principal Arterial-Other within the study area and has a

speed limit of 35 miles per hour.

The area of influence includes the intersections associated with all SR 26 ramps. The ramp

terminal and adjacent intersections analyzed within the area of influence are listed below.

Intersections

o SR 26 at NW 75th Street

o SR 26 at Southbound On and Off-Ramps

o SR 26 at Northbound Off-Ramp

o SR 26 at Northbound On-Ramp

o SR 26 at NW 69th Terrace

The area of influence is shown in Figure 1-1.

2.2. Analysis Years The following study years are established for this IOAR:

Existing Year: 2018

Opening Year: 2019

Design Year: 2029

2.3. Data Collection and Sources Existing data was provided in the Safety Study (Appendix A) prepared in October 2014, by the

Florida Department of Transportation (Department), District 2 Traffic Operations Office. The

Safety Study’s purpose was to identify improvements at the study interchange and adjacent

intersections along SR 26 that would improve operations and safety.

Standard K and D factors were not needed for this report because traffic developed for this IOAR

was developed using growth rates applied to the existing traffic from the Safety Study. The

2.0 METHODOLOGY I-75 at SR 26 IOAR

4

design hour truck percentage and peak hour factor were determined based on the traffic counts

performed as part of the 2014 Safety Study.

2.4. Travel Demand Forecasting The February 2014 traffic counts from the Safety Study were obtained for this IOAR and

checked for reasonableness. A growth rate was then applied to the traffic counts to develop

existing year, opening year and design year traffic volumes for the IOAR. The growth rate was

developed based on historic growth trends, the growth from the latest version of the Gainesville

Metropolitan Transportation Planning Organization (MTPO) Model and growth rate from the

Relief Study Model (RSM). Growth rate development and future traffic development are further

discussed in Section 5.

2.5. Operational Analysis Procedures Traffic operational analysis has been conducted for the analysis years for the No-Build and Build

Alternatives. Intersection analysis has been conducted for the study intersections using the most

recent version of Synchro.

2.6. LOS Criteria FDOT Topic No. 525-000-006 provides LOS targets for the State Highway System (SHS). The

term LOS is defined as the system of six designated ranges from “A” (best) to “F” (worst) used

to evaluate roadway facility performance. The FDOT minimum acceptable operating LOS

targets were used for this IOAR. The LOS target for study intersections analyzed in this IOAR

are summarized below:

Signalized Intersections: LOS D

3.0 EXISTING CONDITIONS I-75 at SR 26 IMR

5

3. EXISTING CONDITIONS This Section discusses the existing roadway and traffic conditions at the study interchange of I-

75 at SR 26.

3.1. Typical Sections The I-75 typical section at SR 26 consists of a six lane divided section providing three general

purpose lanes in both directions. I-75 is classified as an Urban Principal Arterial - Interstate. The

SR 26 typical section within the limits of the limited access right-of-way is a five lane urban

divided roadway with a raised landscaped median west of I-75 and a six lane urban divided

roadway with a raised landscaped median to the east of I-75. SR 26 is classified as an Urban

Principal Arterial - Other.

3.2. Study Interchange The study interchange is a partial diamond interchange with a loop ramp in the southwest

quadrant. An aerial of the interchange is provided in Figure 3-1.

Figure 3-1: I-75 at SR 26 Existing Layout

NW

75

th S

tree

t

26

NW

69

th T

erra

ce

Newberry Road


6

3.3. Intersection Geometry The study intersections that will be analyzed as part of this IOAR include:

SR 26 at NW 75th Street


SR 26 at I-75 Northbound Off-Ramp



The SR 26 at NW 75th Street intersection is a four-leg signalized intersection. The intersection is

located approximately 1,000 feet west of I-75. The intersection has the following lane

configuration.

Eastbound direction: one left turn lanes, two through lanes and one shared through/right

turn lane

Westbound direction: two left turn lanes, one through lane and one shared through/right

turn lane

Northbound direction: one shared through/left turn lane and two right turn lanes

Southbound direction: one shared left/through/right turn lane

The SR 26 at I-75 Southbound Ramps is a four-leg signalized intersection. This is a ramp

terminal intersection. The intersection has the following lane configuration.

Eastbound direction: one left turn lane, three through lanes and one right turn lane

Westbound direction: one left turn lane, two through lanes and one shared through/right

turn lane

Northbound direction: one left turn lane, one through lane and one right turn lane

Southbound direction: one left turn lane and one shared through/right turn lane

The SR 26 at I-75 Northbound Off-Ramp is a three-leg signalized intersection. This is a ramp


Eastbound direction: three through lanes

Westbound direction: three through lanes

Northbound direction: two left turn lanes and two right turn lanes

The SR 26 at I-75 Northbound On-Ramp is a two-leg signalized intersection. This is a ramp


Eastbound direction: one left turn lane and three through lanes

Westbound direction: two through lanes and one shared through/right turn lane


7

The SR 26 at NW 69th Terrace intersection is a four-leg signalized intersection. The intersection

is located approximately 750 feet east of I-75. The intersection has the following lane

configuration.

Eastbound direction: one left turn lane, two through lanes and one shared through/right

turn lane

Westbound direction: one left turn lane, two through lanes and one shared through/right

turn lane

Northbound direction: one shared through/left turn lane and one right turn lane

Southbound direction: one shared through/left turn lane and one right turn lane

The existing lane configuration is provided in Figure 3-2.

3.4. Existing Operational Performance This section summarizes the existing traffic and operational analysis performed within the area

of influence to assess the mobility conditions. This facility accommodates interstate and regional

mobility for commuter and freight traffic.

3.4.1. Existing Traffic Data

A Safety Study was completed in October 2014 for the study interchange. The Safety Study has

an Existing Year of 2014 and provides traffic volumes for the study intersections. For this

IOAR, the Existing Year 2018 traffic development methodology required a growth rate of 1% be

applied to the Safety Study’s existing year 2014 traffic volumes. Further discussion of the

growth rate development is provided in Section 5.1. The Existing Year 2018 traffic volumes are

provided in Figure 3-3.

3.4.2. Operational Analysis

Existing Year 2018 Intersections Analysis

The results of the intersections analysis for Existing Year 2018 are shown in Figure 3-4 and

Table 3-1. Documentation of the Existing Year analysis is provided in Appendix B.

Table 3-1: Existing Year 2018 Intersection Analysis Results

Intersection

AM Peak Hour PM Peak Hour

Delay

(sec) LOS

Delay

(sec) LOS

SR 26 at NW 75th Street 82.8 F 57.6 E

SR 26 at Southbound Ramps 79.1 E 37.4 D

SR 26 at Northbound Off-Ramp 31.7 C 38.9 D

SR 26 at Northbound On-Ramp 13.9 B 10.7 B

SR 26 at NW 69th Terrace 54.8 D 59.1 E


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The Existing Year 2018 intersection analysis shows that the Northbound Off-Ramp and

Northbound On-Ramp intersections operate at LOS D or better in the AM and PM peak hours.

The NW 75th Street, Southbound Ramps and NW 69th Terrace intersections operate below LOS

D in the AM and/or PM peak hours. Multiple movements operate at LOS F during the AM

and/or PM peak hours in the existing conditions. The following movements operate at LOS F.


o Eastbound left (PM peak hour)

o Eastbound through (AM peak hour)

o Westbound left (AM and PM peak hours)

o Northbound through (AM and PM peak hours)

o Southbound through (AM and PM peak hours)

SR 26 at Southbound Ramps



o Northbound left (PM peak hour)

o Northbound right (AM peak hour)

SR 26 at Northbound Off-Ramp

o Northbound left (AM and PM peak hours)

o Northbound right (AM and PM peak hours)

SR 26 at Northbound On-Ramp



o Eastbound left (AM and PM peak hours)

o Westbound through (AM peak hour)

o Southbound through (AM peak hour)

o Southbound right (PM peak hour)


9

Existing Year 2018 Queuing Analysis

Table 3-2 summarizes the results of the study intersections 95th percentile queue analysis for the

AM and PM peak hours. In order to provide operationally efficient and safe conditions, queuing

needs to be within the provided storage. The following movement’s queues are beyond the

available storage:


o Eastbound through (AM and PM peak hours)


o Westbound through (PM peak hour)










o Eastbound left (AM peak hour)




No queues at the ramp terminals back up to the I-75 mainline.


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Table 3-2: Existing Year 2018 Signals Queuing Analysis Results

Intersection Time

Period

Eastbound Westbound Northbound Southbound

Left Through Right Left Through Right Left Through Right Left Through Right

SR 26 at

NW 75th

Street

AM

Peak 29 #765 #569 127 #375 #814 96

PM

Peak 80 476 #577 #1167 #620 133 139

Existing

Storage

(feet)

240 415 415 500 650 650 670 - - 150

SR 26 at

Southbound

Ramps

AM

Peak m25 m774 m0 #381 m191 #293 25 #965 41 31

PM

Peak m16 204 m18 m#728 m434 #278 11 59 28 54

Existing

Storage

(feet)

250 670 600 160 420 420 150 - 150 85 85

SR 26 at

Northbound

Off-Ramp

AM

Peak m118 53 #309 #437

PM

Peak 145 61 #581 #340

Existing

Storage

(feet)

- 420 - - 250 - 930 - 1,200 - - -

SR 26 at

Northbound

On-Ramp

AM

Peak m136 m0 m105

PM

Peak 325 m0 m168

Existing

Storage

(feet)

240 - - - 225 225 - - - - - -

SR 26 at

NW 69th

Terrace

AM

Peak #788 782 48 #558 76 0 139 47

PM

Peak #169 477 145 890 171 53 195 #752

Existing

Storage

(feet)

250 520 520 185 740 740 190 190 190 - - 265

# 95th percentile volume exceeds capacity, queue may be longer.

m - Queue is metered by the upstream intersection.

Legend:

Exis ng Lanes

Study Intersec on

SR 26

NW 75th St.

Figure 3‐2 I‐75 at SR 26 (Newberry Road) IOAR

I‐75 SB

On/Off Ra

mps

I‐75 NB Off Ra

mp

I‐75 NB On Ra

mp

SR 26

NW 69th Terr.

Exis ng Lane Configura on

198 (205) 1,555 (829)

157 (266

)

2,963 (1,649)

Delay: 82.8 (57.6)

LOS: F (E)

Legend:

XXX (XXX): 2018 AM (PM) Volumes

Delay: Seconds per vehicle

LOS: A‐F

: Study Intersec on

SR 26

NW 75th St.


I‐75 SB

On/Off

I‐75 NB Off Ra

mp

I‐75 NB On Ra

mp

NW 69th Terr.

Exis ng Year 2018 Peak Hour Volumes and LOS

7 (8)

1,23

9 (827

)

9 (34)

157 (261)

2 (14)

31 (3

7)

17 (2

7)

620 (1,564) 22 (50)

734 (875)

2,374 (1,500)

26 (1

00)

11 (2

) 7 (98)

550 (85)

35 (79)

76 (1

14)

1,148 (2,296) 186 (39)

18 (81)

2 (4)

122 (371

)

1,068 (2,106)

239 (583)

354 (641

) 46

7 (337

)

1,058 (2,119)

2,718 (1,547)

1,157 (2,340)

170 (351)

2,165 (1,240)

677 (437)

168 (180

) 7 (2)

554 (285

)

Delay: 13.9 (10.7)

LOS: B (B)

Delay: 31.7 (38.9)

LOS: C (D)

Delay: 54.8 (59.1)

LOS: D (E)

23 (10) 11

(3)

5 (20)

19 (1

1)

25 (32)

Delay: 79.1 (37.4)

LOS: E (D)


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3.4.3. Crash and Safety Information

Vehicular crash data along SR 26 was obtained from the FDOT State Safety Office Map Based

Query Tool (SSOGis). SSOGis is a database maintained annually by FDOT for crashes reported

along state highway facilities. The database provides information on various characteristics

associated with each crash including: collision type, severity, weather conditions, road surface

conditions and date/time information. The crash data was collected for the most recent five years

available (2012-2016). The crashes were analyzed to make an assessment of safety conditions at

the intersections within the project limits. The existing crash analysis performed for this IOAR is

consistent with the methods outlined in the Highway Safety Manual 1st Edition (HSM). In this

section, the existing crash analysis will be broken down between the study intersections. The raw

crash data is provided in Appendix C.

The existing crashes were first segmented based on intersection segmentation outlined in Chapter

12 of the HSM. After segmenting the study intersections, the crash frequency and crash rate were

calculated for each intersection. The ‘Average Crash Rate Method’ of crash analysis, based on

AADT and number of crashes occurred, was used for calculating actual crash rate for the

roadway segments. The actual crash rate for the study corridors from year 2012 to 2016 was

compared with the statewide average crash rate for the same type of facility. All the study

intersections in the study area have a crash rate higher than the statewide average except at the

SR 26 at Northbound On-Ramp intersection.


The crash analysis results reveal that there was a total of 114 crashes at the SR 26/NW 75th Street

intersection during the five study years (2012-2016). Of these 114 crashes, front to rear (rear

end) were the most common type of crash accounting for 47% of total crashes followed by angle

crashes accounting for 26% of total crashes at this intersection. There were 46 total injuries and

no fatalities. The average crash rate for this intersection is higher than the statewide average

crash rate for similar facilities. Summaries of the crash analysis are provided in Figure 3-4,

Table 3-3 and Table 3-8.


14

Figure 3-4: SR 26 at NW 75th Street Crash Types (2012-2016)

Table 3-3: SR 26 at NW 75th Street Severity Summary (2012-2016)

Injury Type 2012 2013 2014 2015 2016 Total Percent

of Total

Number of

Property

Damage Only

Crashes

13 21 22 13 9 78 68%

Number of

Crashes

with Injuries

5 7 9 5 10 36 32%

Number of

Crashes

with Fatalities

0 0 0 0 0 0 0%

Total 18 28 31 18 19 114 100%

Number of

Injuries 7 7 11 9 12 46

Number of

Fatalities 0 0 0 0 0 0


The crash analysis results reveal that there was a total of 106 crashes at the SR 26/Southbound

Ramps intersection during the five study years (2012-2016). Of these 106 crashes, front to rear

(rear end) were the most common type of crash accounting for 49% of total crashes followed by

angle crashes accounting for 30% of total crashes at this intersection. There were 73 total injuries

47%

4%

26%

14%

1%

2%0%

6%

0%

Crash Type at NW 75th Street

Front to Rear (Rear End)

Front to Front

Angle

Sideswipe, same direction

Sideswipe, opposite direction

Rear to Side

Rear to Rear

Other

Unknown


15

and no fatalities. The average crash rate for this intersection is higher than the statewide average



Figure 3-5: SR 26 at Southbound Ramps Crash Types (2012-2016)

Table 3-4: SR 26 at Southbound Ramps Severity Summary (2012-2016)


of Total

Number of

Property

Damage Only

Crashes

17 5 13 16 9 60 57%

Number of

Crashes

with Injuries

14 4 5 14 9 46 43%

Number of

Crashes

with Fatalities

0 0 0 0 0 0 0%

Total 31 9 18 30 18 106 100%

Number of

Injuries 20 6 9 27 11 73

Number of


49%

2%

30%

9%

2%0% 0%

8%

0%

Crash Type at Southbound Ramps


Front to Front

Angle



Rear to Side

Rear to Rear

Other

Unknown


16


The crash analysis results reveal that there was a total of 125 crashes at the SR 26/Northbound

Off-Ramp intersection during the five study years (2012-2016). Of these 125 crashes, front to

rear (rear end) were the most common type of crash accounting for 54% of total crashes followed

by angle crashes accounting for 19% of total crashes at this intersection. There were 62 total

injuries and no fatalities. The average crash rate for this intersection is higher than the statewide

average crash rate for similar facilities. Summaries of the crash analysis are provided in Figure

3-6, Table 3-5 and Table 3-8.

Figure 3-6: SR 26 at Northbound Off-Ramp Crash Types (2012-2016)

54%

0%

19%

18%

0%

0%

0%9%

0%

Crash Type at Northbound Off-Ramp


Front to Front

Angle



Rear to Side

Rear to Rear

Other

Unknown


17

Table 3-5: SR 26 at Northbound Off-Ramp Severity Summary (2012-2016)


of Total

Number of

Property

Damage Only

Crashes

18 15 8 17 29 87 70%

Number of

Crashes

with Injuries

8 9 4 9 8 38 30%

Number of

Crashes

with Fatalities

0 0 0 0 0 0 0%

Total 26 24 12 26 37 125 100%

Number of

Injuries 12 18 9 12 11 62

Number of



The crash analysis results reveal that there was a total of 23 crashes at the SR 26/Northbound

On-Ramp intersection during the five study years (2012-2016). Of these 23 crashes, front to rear



and no fatalities. The average crash rate for this intersection is not higher than the statewide

average crash rate for similar facilities. Summaries of the crash analysis are provided in Figure

3-7, Table 3-6 and Table 3-8.


18

Figure 3-7: SR 26 at Northbound On-Ramp Crash Types (2012-2016)

Table 3-6: SR 26 at Northbound On-Ramp Severity Summary (2012-2016)


of Total

Number of

Property

Damage Only

Crashes

2 5 0 2 5 14 61%

Number of

Crashes

with Injuries

4 0 0 2 3 9 39%

Number of

Crashes

with Fatalities

0 0 0 0 0 0 0%

Total 6 5 0 4 8 23 100%

Number of

Injuries 4 0 0 2 4 10

Number of



The crash analysis results reveal that there was a total of 114 crashes at the SR 26/NW 69th

Terrace intersection during the five study years (2012-2016). Of these 114 crashes, front to rear



44%

0%

22%

17%

0%

0% 0%

17%

0%

Crash Type at Northbound On-Ramp


Front to Front

Angle



Rear to Side

Rear to Rear

Other

Unknown


19

and no fatalities. The average crash rate for this intersection is higher than the statewide average



Figure 3-8: SR 26 at NW 69th Terrace Crash Types (2012-2016)

Table 3-7: SR 26 at NW 69th Terrace Severity Summary (2012-2016)


of Total

Number of

Property

Damage Only

Crashes

20 12 10 31 4 77 68%

Number of

Crashes

with Injuries

15 7 5 7 3 37 32%

Number of

Crashes

with Fatalities

0 0 0 0 0 0 0%

Total 35 19 15 38 7 114 100%

Number of

Injuries 27 23 5 13 8 76

Number of


Table 3-8 further summarizes the existing crash data, and provides the crash frequency and rate

at each of the study intersections.

48%

2%

24%

18%

0%

1%1%

6%

0%

Crash Type at NW 69th Terrace


Front to Front

Angle



Rear to Side

Rear to Rear

Other

Unknown


20

Table 3-8: Study Intersection Crash Summary (2012-2016)

Intersection

Number

of

Crashes

Daily

Entering

(AADT)1

Crash

Frequency

Cash Rate

(crashes/million entering)

Statewide

Average

Crash

Rate

SR 26 at NW 75th

Street 114 34,737 22.8 1.798 0.799

SR 26 at Southbound

Ramps 106 39,477 21.2 1.471 0.484

SR 26 at Northbound

Off-Ramp 125 38,927 25.0 1.760 0.484

SR 26 at Northbound

On-Ramp 23 47,587 4.6 0.265 0.484

SR 26 at NW 69th

Terrace 114 49,048 22.8 1.274 0.799

1 – Average of the AADT based on location provided in Raw Crash Data

3.4.4. Consistency with Master Plans, LRTP and DRIs

The latest adopted transportation programs and plans available were reviewed and are consistent

with the IOAR.

FDOT Five-Year Work Program

Local Government Comprehensive Plans

FDOT’s Strategic Intermodal System Plans

Any other studies or Master Plans

4.0 NEED I-75 at SR 26 IOAR

21

4. NEED The I-75 at SR 26 interchange is an important connection for commuters, dining and retail in the

region.

The goal of this project is to improve traffic operations and safety at the study intersections

through implementation of operational and capacity improvements that will maintain and

improve mobility, support existing and future development and enhance emergency evacuation

and response times.

The need for the project is based on the following factors:

Transportation Capacity

Currently, the I-75 at SR 26 interchange is the major access point for the City of Gainesville. It

currently experiences heavy congestion and due to this, queues form at the off ramps and

between intersections at the study interchange.

As a result, future traffic demand on this major arterial will need to be addressed.

Existing Safety Concerns

The study intersections have been a prime safety concern to FDOT for some time. A review of

the Department’s High Crash intersection and segment lists was conducted as part of this IMR.

The high crash location lists do not go beyond the year 2013. The segment list indicated that SR

26 was identified as a high crash segment from 2010-2013. Also, all of the study intersections

were listed as high crash intersections from 2011-2013. In order to address these major safety

concerns along SR 26 and at the study intersections, a Safety Study was performed in October of

2014. Since the Safety Study was completed, safety has continued to be a major concern along

SR 26 and at the study intersections.

As a result, improvements to the SR 26 arterial need to be implemented to address the existing

safety concerns.

Emergency Evacuation and Response Times

I‐75 serves as part of the emergency evacuation route network designated by the Florida Division

of Emergency Management. As designated evacuation facility this roadway is critical in

facilitating traffic flow during emergency evacuation periods.

5.0 FUTURE NO-BUILD CONDITIONS I-75 at SR 26 IOAR

22

5. FUTURE NO-BUILD CONDITIONS This section documents the future conditions within the I-75 at SR 26 interchange area of

influence for the No-Build Alternative. The No-Build Alternative assumes the existing plus

committed roadway network. At this time, there are no committed roadway projects, so, the No-

Build will match existing conditions.

The No-Build lane configuration is provided in Figure 5-1.

The analysis years considered under the No-Build Alternative are Opening Year 2019 and

Design Year 2029. The operational analysis includes the future year peak hour traffic forecasts

for the area of influence. The primary objective of this analysis was to establish the No-Build

operational conditions at the study interchange and intersections.

5.1. Future Traffic Forecast In order to develop future volumes, a compound annual growth rate for the entire project area

was developed. The growth rates from the FTI historical counts, Gainesville MTPO model and

the RSM were summarized and compared. The RSM was developed as part of the recently

completed North I-75 Master Plan. The RSM is based on the latest socio-economic data obtained

from the local Metropolitan Planning Organizations (MPOs). The final growth rate was based on

the comparison of these sources. The final growth rate was decided because it provided the best

representation of the traffic trends in the area. A compound annual growth rate of 1.0% was

applied to the Existing Year traffic to develop the 2019 and 2029 traffic. Table 5-1, Table 5-2

and Table 5-3 provide a summary of the growth rate development.

Table 5-1: FTI Historic Counts Growth Rate

Description 2014 AADT 2016 AADT CAGR1

SR 26 W of I-75 49,500 51,000 1.5%

SR 26 E of I-75 50,000 49,500 -0.5%

SR 26 E of NW 69th Terrace - - -

I-75 SB On-Ramp 8,100 7,000 -7.0%

I-75 NB Off-Ramp 8,500 9,000 2.9%

I-75 SB Off-Ramp 5,300 4,800 -4.8%

I-75 NB On-Ramp 5,300 5,500 1.9% 1. CAGR = Compound Annual Growth Rate


23

Table 5-2: Gainesville MTPO Model Growth Rate


SR 26 W of I-75 59,889 67,761 0.4%

SR 26 E of I-75 59,037 67,686 0.5%

SR 26 E of NW 69th Terrace 52,307 60,099 0.5%

I-75 SB On-Ramp 9,458 8,985 -0.2%

I-75 NB Off-Ramp 8,988 8,496 -0.2%

I-75 SB Off-Ramp 8,799 9,700 0.3%

I-75 NB On-Ramp 8,613 9,998 0.5% 1. CAGR = Compound Annual Growth Rate

Table 5-3: RSM Growth Rate


I-75 N of I-10 74,400 106,600 1.4%

Ramps N of I-10 15,200 19,500 1.0%

Ramps S of I-10 20,400 32,900 1.9%

I-75 S of I-10 79,600 120,000 1.7% 1. CAGR = Compound Annual Growth Rate

The percentage splits in future years were kept same as existing. The final 2019 and 2029 traffic

was balanced and checked for reasonableness.

Opening Year 2019 and Design Year 2029 traffic is shown in Figure 5-2 and Figure 5-3

respectively.

5.2. Operational Analysis Opening Year 2019 and Design Year 2029 No-Build Intersections Analysis

Intersection analysis was performed for Opening Year 2019 and Design Year 2029 using the

latest version of Synchro. Intersection analysis was performed for the study intersections. All the

study intersections are signalized. Delay and LOS were reported for the intersections as

Measures of Effectiveness (MOEs) used in evaluation. The results of the intersection analysis for

Opening Year 2019 and Design Year 2029 are shown in Figure 5-2 and Figure 5-3 and Table 5-

4 and Table 5-5 respectively. Documentation of the No-Build Alternative analysis is provided in

Appendix D.


24

Table 5-4: Opening Year 2019 No-Build Intersection Analysis Results

Intersection


Delay

(sec) LOS

Delay

(sec) LOS

SR 26 at NW 75th Street 83.7 F 76.0 E

SR 26 at Southbound Ramps 80.4 F 46.2 D

SR 26 at Northbound Off-Ramp 32.8 C 39.1 D

SR 26 at Northbound On-Ramp 17.3 B 23.1 C

SR 26 at NW 69th Terrace 56.7 E 61.8 E

The Opening Year 2019 intersection analysis shows that the Northbound Off-Ramp and




and/or PM peak hours with the existing conditions; the following movements operate at LOS F.





o Northbound through (PM peak hour)



















25

Table 5-5: Design Year 2029 No-Build Intersection Analysis Results

Intersection


Delay

(sec) LOS

Delay

(sec) LOS

SR 26 at NW 75th Street 102.7 F 92.1 F

SR 26 at Southbound Ramps 90.1 F 64.9 E

SR 26 at Northbound Off-Ramp 42.1 D 48.5 D

SR 26 at Northbound On-Ramp 35.8 D 30.2 C

SR 26 at NW 69th Terrace 81.3 F 76.6 E

The Design Year 2029 intersection analysis shows that the Northbound Off-Ramp and




and/or PM peak hours with the existing conditions; the following movements operate at LOS F.


























26

Opening Year 2019 and Design Year 2029 No-Build Queuing Analysis

Table 5-6 and Table 5-7 summarizes the results of the study intersections 95th percentile queue

analysis for the AM and PM peak hours. In order to provide operationally efficient and safe

conditions queuing needs to be within the provided storage. The following movement’s queues

are beyond the available storage in Opening Year 2019:



















No queues at the ramp terminals back up to the I-75 mainline. However, there are queues along

SR 26 that will back up into adjacent intersections affecting operations at adjacent intersections

such as the eastbound left queue at NW 69th Terrace.


27

Table 5-6: Opening Year 2019 No-Build Signals Queuing Analysis Results

Intersection Time

Period



SR 26 at

NW 75th

Street

AM

Peak 29 #801 #606 118 #328 #764 96

PM

Peak 78 449 #671 #1208 #583 148 137

Existing

Storage

(feet)

240 415 415 500 650 650 670 - - 150

SR 26 at

Southbound

Ramps

AM

Peak m26 m858 m0 #374 m328 #286 25 #957 40 31

PM

Peak m15 284 14 m#734 m760 #277 11 58 28 53

Existing

Storage

(feet)

250 670 600 160 420 420 150 - 150 85 85

SR 26 at

Northbound

Off-Ramp

AM

Peak m110 53 #313 #443

PM

Peak 410 63 #561 #328

Existing

Storage

(feet)

- 420 - - 250 - 930 - 1,200 - - -

SR 26 at

Northbound

On-Ramp

AM

Peak m125 m0 m105

PM

Peak 324 m0 m282

Existing

Storage

(feet)

240 - - - 225 225 - - - - - -

SR 26 at

NW 69th

Terrace

AM

Peak #835 831 48 #569 76 0 142 48

PM

Peak #184 686 145 881 170 53 195 #753

Existing

Storage

(feet)

250 520 520 185 740 740 190 190 190 - - 265




28

The following movement’s 95th percentile queues are beyond the available storage in Design

Year 2029:




















SR 26 that will back up into adjacent intersections affecting operations at adjacent intersections.


29

Table 5-7: Design Year 2029 No-Build Signals Queuing Analysis Results

Intersection Time

Period



SR 26 at

NW 75th

Street

AM

Peak 33 #919 #675 171 #422 #1001 102

PM

Peak 84 #575 m#694 m#1372 #701 196 148

Existing

Storage

(feet)

240 415 415 500 650 650 670 - - 150

SR 26 at

Southbound

Ramps

AM

Peak m25 m857 m0 #412 m324 #275 27 #1089 45 34

PM

Peak m16 m245 m8 m#804 m854 #333 11 61 30 57

Existing

Storage

(feet)

250 670 600 160 420 420 150 - 150 85 85

SR 26 at

Northbound

Off-Ramp

AM

Peak m237 53 #348 #500

PM

Peak 409 m66 #641 #380

Existing

Storage

(feet)

- 420 - - 250 - 930 - 1,200 - - -

SR 26 at

Northbound

On-Ramp

AM

Peak m127 m0 m146

PM

Peak 354 m0 m227

Existing

Storage

(feet)

240 - - - 225 225 - - - - - -

SR 26 at

NW 69th

Terrace

AM

Peak m#1099 #1247 52 #632 80 0 152 63

PM

Peak #213 749 #173 #1163 190 56 #219 #845

Existing

Storage

(feet)

250 520 520 185 740 740 190 190 190 - - 265



Legend:

Exis ng Lanes

Study Intersec on

SR 26

NW 75th St.


I‐75 SB

On/Off Ra

mps

I‐75 NB Off Ra

mp

I‐75 NB On Ra

mp

SR 26

NW 69th Terr.

No‐Build Lane Configura on

200 (207) 1,571 (837)

159 (269

)

2,993 (1,665)

Delay: 83.7 (76.0)

LOS: F (E)

Legend:



LOS: A‐F

: Study Intersec on

SR 26

NW 75th St.


I‐75 SB

On/Off

I‐75 NB Off Ra

mp

I‐75 NB On Ra

mp

NW 69th Terr.

Opening Year 2019 No‐Build Peak Hour Volumes and LOS

7 (8)

1,25

1 (835

)

9 (34)

159 (264)

2 (14)

31 (3

7)

17 (2

7)

626 (1,580) 22 (51)

741 (884)

2,398 (1,515)

26 (1

01)

11 (2

) 7 (99)

556 (86)

35 (80)

77 (1

15)

1,159 (2,319) 188 (39)

18 (82)

2 (4)

123 (375

)

1,079 (2,127)

241 (589)

358 (647

) 47

2 (340

)

1,069 (2,140)

2,745 (1,562)

1,169 (2,363)

172 (355)

2,187 (1,252)

684 (441)

170 (182

) 7 (2)

560 (288

)

Delay: 17.3 (23.1)

LOS: B (C)

Delay: 32.8 (39.1)

LOS: C (D)

Delay: 56.7 (61.8)

LOS: E (E)

23 (10) 11

(3)

5 (20)

19 (1

1)

25 (32)

Delay: 80.4 (46.2)

LOS: F (D)

221 (229) 1,735 (925)

176 (297

)

3,306 (1,839)

Delay: 102.7 (92.1)

LOS: F (F)

Legend:



LOS: A‐F

: Study Intersec on

SR 26

NW 75th St.


I‐75 SB

On/Off

I‐75 NB Off Ra

mp

I‐75 NB On Ra

mp

NW 69th Terr.

Design Year 2029 No‐Build Peak Hour Volumes and LOS

8 (9)

1,38

2 (922

)

10 (38)

176 (292)

2 (15)

34 (4

1)

19 (3

0)

691 (1,745) 24 (56)

819 (976)

2,649 (1,674)

29 (1

12)

12 (2

) 8 (109

)

614 (95)

39 (88)

85 (1

27)

1,280 (2,562) 208 (43)

20 (91)

2 (4)

136 (414

)

1,192 (2,350)

266 (651)

395 (715

) 52

1 (376

)

1,181 (2,364)

3,032 (1,725)

1,291 (2,610)

190 (392)

2,416 (1,383)

756 (487)

188 (201

) 8 (2)

619 (318

)

Delay: 35.8 (30.2)

LOS: D (C)

Delay: 42.1 (48.5)

LOS: D (D)

Delay: 81.3 (76.6)

LOS: F (E)

25 (11) 12

(3)

6 (22)

21 (1

2)

28 (35)

Delay: 90.1 (64.9)

LOS: F (E)

6.0 BUILD CONDITIONS I-75 at SR 26 IOAR

33

6. BUILD CONDITIONS

6.1. Build Alternative

The Build Alternative incorporates the following short term roadway improvements

recommended in this IOAR:


Westbound direction: provide two left turn lanes

Northbound direction: provide two right turn lanes and convert the through lane to a

shared through/left turn lane


Eastbound direction: provide two left turn lanes

Westbound direction: convert the shared through/right turn lane to through lane and add

one right turn lane


Eastbound direction: provide two left turn lanes

As part of the Build Alternative, all signals timings were optimized, and the yellow and all red

clearance intervals were increased per the current FDOT standards.

The Build Alternative lane configuration figure with all improvements shown in red is provided

in Figure 6-1. The travel demand forecast for the project assumes that the above improvements

would not impact overall future traffic flow patterns within the study. Therefore, the future year

peak hour turning movement volume forecasts for the No-Build Alternative are also evaluated

for the Build Alternative. Opening Year 2019 and Design Year 2029 traffic is shown in Figure

6-2 and Figure 6-3 respectively. The Build Alternative concept design is provided in Appendix

F.


34

6.2. Operational Analysis Opening Year 2019 and Design Year 2029 Build Intersections Analysis

The results of the intersections analysis for Opening Year 2019 and Design Year 2029 are shown

in Figure 6-2 and Figure 6-3 and Table 6-1 and Table 6-2 respectively. Documentation of the

Build Alternative analysis is provided in Appendix E.

Table 6-1: Opening Year 2019 Build Intersection Analysis Results

Intersection


Delay

(sec) LOS

Delay

(sec) LOS

SR 26 at NW 75th Street 68.9 E 74.6 E

SR 26 at Southbound Ramps 26.5 C 26.2 C

SR 26 at Northbound Off-Ramp 22.8 C 34.8 C

SR 26 at Northbound On-Ramp 5.4 A 7.4 A

SR 26 at NW 69th Terrace 33.7 C 36.2 D

The Opening Year 2019 intersection analysis shows that all intersections operate at LOS D or

better in the AM and PM peak hours except the NW 75th Street intersection. However, there are

multiple movements operate at LOS F during the AM and/or PM peak hours with the proposed

improvements; the following movements operate at LOS F.










o Westbound left (AM peak hour)



o Southbound Left (AM peak hour)



o Northbound right (PM peak hour)





35



Table 6-2: Design Year 2029 Build Intersection Analysis Results

Intersection


Delay

(sec) LOS

Delay

(sec) LOS

SR 26 at NW 75th Street 99.5 F 89.8 F

SR 26 at Southbound Ramps 53.2 D 41.5 D

SR 26 at Northbound Off-Ramp 36.9 D 44.1 D

SR 26 at Northbound On-Ramp 13.9 B 11.9 B

SR 26 at NW 69th Terrace 46.5 D 46.6 D

The Design Year 2029 intersection analysis shows that all intersections operate at LOS D or

better in the AM and PM peak hours except the NW 75th Street intersection. The LOS at the

Southbound Ramps and NW 69th Terrace intersections improve to LOS D versus LOS F for the

No-Build Alternative. Also, the delay and LOS improve at all study intersections compared to

the No-Build. Even with these improvements, there are multiple movements operate at LOS F

during the AM and/or PM peak hours with the proposed improvements; the following

movements operate at LOS F.



o Eastbound through (AM and PM peak hour)










o Southbound Left (AM peak hour)








36



Opening Year 2019 and Design Year 2029 Build Queuing Analysis

Table 6-3 and Table 6-4 summarizes the results of the study intersections’ 95th percentile queue

analysis for the AM and PM peak hours. In order to provide operationally efficient and safe

conditions queuing needs to be within the provided storage. The following movements’ queues

are beyond the available storage in Opening Year 2019:






o Westbound left (PM peak hour)












37

Table 6-3: Opening Year 2019 Build Signals Queuing Analysis Results

Intersection Time

Period



SR 26 at

NW 75th

Street

AM

Peak 30 #892 #538 194 #360 #782 101

PM

Peak 78 #528 #522 #1171 #624 112 137

Existing

Storage

(feet)

240 415 415 500 650 650 670 - - 150

SR 26 at

Southbound

Ramps

AM

Peak m19 m543 m101 150 223 155 156 221 53 34

PM

Peak 33 355 52 #334 866 168 166 49 35 54

Existing

Storage

(feet)

250 670 600 160 420 420 150 - 150 85 85

SR 26 at

Northbound

Off-Ramp

AM

Peak 316 14 257 #377

PM

Peak 282 56 #561 #328

Existing

Storage

(feet)

- 420 - - 250 - 930 - 1,200 - - -

SR 26 at

Northbound

On-Ramp

AM

Peak m89 0 130 29

PM

Peak 167 m0 m177 m43

Existing

Storage

(feet)

240 - - - 225 225 - - - - - -

SR 26 at

NW 69th

Terrace

AM

Peak 361 765 #68 522 80 0 149 58

PM

Peak 80 528 145 881 170 53 195 #504

Existing

Storage

(feet)

250 520 520 185 740 740 190 190 190 - - 265




38

Ramp queue lengths at the Southbound Ramps and Northbound Off-Ramp intersections reduce

compared to the No-Build Alternative. Left turning movement queues at the ramp terminals and

NW 69th Terrace also reduce. However, there are still movements that exceed the existing

storage. The following movements are beyond the available storage in Design Year 2029:


















39

Table 6-4: Design Year 2029 Build Signals Queuing Analysis Results

Intersection Time

Period



SR 26 at

NW 75th

Street

AM

Peak 34 #1041 #638 298 #416 #965 107

PM

Peak 84 #628 #630 #1376 #711 163 148

Existing

Storage

(feet)

240 415 415 500 650 650 670 - - 150

SR 26 at

Southbound

Ramps

AM

Peak m21 m561 m115 #211 244 168 168 #431 #72 37

PM

Peak 35 407 53 #381 #1168 180 184 51 37 58

Existing

Storage

(feet)

250 670 600 160 420 420 150 - 150 85 85

SR 26 at

Northbound

Off-Ramp

AM

Peak m293 38 285 #447

PM

Peak 331 61 #641 #380

Existing

Storage

(feet)

- 420 - - 250 - 930 - 1,200 - - -

SR 26 at

Northbound

On-Ramp

AM

Peak m89 m0 39 m1

PM

Peak 182 m0 m187 m55

Existing

Storage

(feet)

240 - - - 225 225 - - - - - -

SR 26 at

NW 69th

Terrace

AM

Peak m#422 #546 #75 #651 84 0 159 67

PM

Peak 87 565 #173 #1163 190 56 #219 #600

Existing

Storage

(feet)

250 520 520 185 740 740 190 190 190 - - 265



Legend:

Exis ng Lanes

Build Lanes

S Study Intersec on

SR 26

NW 75th St.


I‐75 SB

On/Off Ra

mps

I‐75 NB Off Ra

mp

I‐75 NB On Ra

mp

SR 26

NW 69th Terr.

Build Lane Configura on

200 (207) 1,571 (837)

159 (269

)

2,993 (1,665)

Delay: 68.9 (74.6)

LOS: E (E)

Legend:



LOS: A‐F

: Study Intersec on

SR 26

NW 75th St.


I‐75 SB

On/Off

I‐75 NB Off Ra

mp

I‐75 NB On Ra

mp

NW 69th Terr.

Opening Year 2019 Build Peak Hour Volumes and LOS

7 (8)

1,25

1 (835

)

9 (34)

159 (264)

2 (14)

31 (3

7)

17 (2

7)

626 (1,580) 22 (51)

741 (884)

2,398 (1,515)

26 (1

01)

11 (2

) 7 (99)

556 (86)

35 (80)

77 (1

15)

1,159 (2,319) 188 (39)

18 (82)

2 (4)

123 (375

)

1,079 (2,127)

241 (589)

358 (647

) 47

2 (340

)

1,069 (2,140)

2,745 (1,562)

1,169 (2,363)

172 (355)

2,187 (1,252)

684 (441)

170 (182

) 7 (2)

560 (288

)

Delay: 5.4 (7.4)

LOS: A (A)

Delay: 22.8 (34.8)

LOS: C (C)

Delay: 33.7 (36.2)

LOS: C (D)

23 (10) 11

(3)

5 (20)

19 (1

1)

25 (32)

Delay: 26.5 (26.2)

LOS: C (C)

221 (229) 1,735 (925)

176 (297

)

3,306 (1,839)

Delay: 99.5 (89.8)

LOS: F (F)

Legend:



LOS: A‐F

: Study Intersec on

SR 26

NW 75th St.


I‐75 SB

On/Off

I‐75 NB Off Ra

mp

I‐75 NB On Ra

mp

NW 69th Terr.

Design Year 2029 Build Peak Hour Volumes and LOS

8 (9)

1,38

2 (922

)

10 (38)

176 (292)

2 (15)

34 (4

1)

19 (3

0)

691 (1,745) 24 (56)

819 (976)

2,649 (1,674)

29 (1

12)

12 (2

) 8 (109

)

614 (95)

39 (88)

85 (1

27)

1,280 (2,562) 208 (43)

20 (91)

2 (4)

136 (414

)

1,192 (2,350)

266 (651)

395 (715

) 52

1 (376

)

1,181 (2,364)

3,032 (1,725)

1,291 (2,610)

190 (392)

2,416 (1,383)

756 (487)

188 (201

) 8 (2)

619 (318

)

Delay: 13.9 (11.9)

LOS: B (B)

Delay: 36.9 (44.1)

LOS: D (D)

Delay: 46.5 (46.6)

LOS: D (D)

25 (11) 12

(3)

6 (22)

21 (1

2)

28 (35)

Delay: 53.2 (41.5)

LOS: D (D)


43

6.3. Predictive Safety Analysis A predictive quantitative safety analysis was performed to determine if the proposed

improvements addressed the existing safety concern. The safety analysis performed follows the

guidelines developed in the 2018 IARUG for an IOAR.

Table 6-5 shows the existing number of crashes, reduction in crashes and the total number of

predicted crashes if the Build Alternative is implemented. Crash modification factors (CMF) that

were available were used to help predict the reduction in crashes.

The CMFs for this analysis were determined using the CMF Clearinghouse funded by FHWA. If

more than one CMF was used at an intersection, the CMFs were multiplied together to get one

CMF for the study intersection. Not every improvement recommended has a CMF that correlates

with it. Due to this, quantitative safety analysis can only be performed for specific

improvements, described below. A qualitative safety analysis can then be performed for all other

recommendations. The three CMFs used to quantify the benefits of the project include:

Clearinghouse CMF 4203: Increase yellow interval and all red interval = 0.99 (applied to

all intersections)

Clearinghouse CMF 288: Provide right-turn lane on one major-road approach = 0.91

(applied to SR 26 at NW 75th Street intersection)

Clearinghouse CMF 340: Change from permitted-protected to protected on major

approach (applied to SR 26 at Southbound Ramps intersection)

Table 6-5: Reduction in Crashes

Intersection Existing

Crashes CMF 1 CMF 2 CMF

Predicted

Crashes

Reduction

in Crashes

SR 26 at NW 75th Street 114 0.99 0.91 0.90 103 11

SR 26 at Southbound Ramps 106 0.99 0.58 0.57 61 45

SR 26 at Northbound Off-Ramp 125 0.99 - 0.99 124 1

SR 26 at Northbound On-Ramp 23 0.99 - 0.99 23 0

SR 26 at NW 69th Terrace 114 0.99 - 0.99 113 1

Total 482 - - - 423 59

By implementing the proposed modifications, a total expected crash reduction of 59 crashes a

year is expected.

In addition, some of the proposed improvements cannot be analyzed as part of a quantitative

safety analysis, but based on the safety analysis performed and the reduction in delay and queues

safety should improve with all the recommended improvements.

7.0 EVALUATION OF ALTERNATIVES I-75 at SR 26 IOAR

44

7. EVALUATON OF ALTERNATIVES This section discusses the analysis of alternatives based on safety, engineering and operational.

The No-Build Alternative was evaluated in Section 5 and the Build Alternative in Section 6. A

comparison of the No-Build and the Build Alternative is also provided in this section. The

evaluation criteria are described as follows:

Compliance with FHWA Requirements

Traffic Operational Performance

7.1. Compliance with Policies and Engineering Standards The design criteria for this project is based on design parameters outlined in the FDOT Florida

Design Manual, the FDOT Manual of Uniform Minimum Standards for Design, Construction

and Maintenance for Streets and Highways and AASHTO’s A Policy on Geometric Design of

Highway and Streets published in 2011.

7.2. Alternatives Comparison The No-Build Alternative and the Build Alternative were compared and a summary is provided

in the sections below.

7.2.1. Operational Comparison

Based on the analysis, the Build Alternative provides significant improvements over the No-

Build condition at the ramp terminals and NW 69th Terrace intersections. A comparison of the

Design Year 2029 No-Build and Build results are provided in Table 7-1.

Table 7-1: Design Year 2029 No-Build and Build Alternatives Intersections

Comparison

Intersection

2029 No-Build 2029 Build

AM Peak Hour PM Peak Hour AM Peak Hour PM Peak Hour

Delay

(sec) LOS

Delay

(sec) LOS

Delay

(sec) LOS

Delay

(sec) LOS

SR 26 at NW 75th Street 102.7 F 92.1 F 99.5 F 89.8 F

SR 26 at Southbound Ramps 90.1 F 64.9 E 53.2 D 41.5 D

SR 26 at Northbound Off-Ramp 42.1 D 48.5 D 36.9 D 44.1 D

SR 26 at Northbound On-Ramp 35.8 D 30.2 C 13.9 B 11.9 B

SR 26 at NW 69th Terrace 81.3 F 76.6 E 46.5 D 46.6 D

7.0 EVALUATION OF ALTERNATIVES I-75 at SR 26 IOAR

45

The Build Alternative will improve the delay at all the study intersections. The biggest

improvements in delay and LOS occur at the Southbound Ramps, Northbound On-Ramp and

NW 69th Terrace intersections. The delay at the Southbound Ramps is reduced by 36.9 seconds

and 23.4 seconds during the AM and PM peak hours, respectively. The delay at the Northbound

On-Ramp is reduced by 21.9 seconds and 18.3 seconds during the AM and PM peak hours,

respectively. The delay at NW 69th Terrace is reduced by 34.8 seconds and 30.0 seconds during

the AM and PM peak hours, respectively.

The Build Alternative will also improve the queues at the study intersections compared to the

No-Build Alternative. One major improvement was the ramp queues at the ramp terminals. For

example, the queues along the ramps at the Southbound Ramps intersection reduce by up to 658

feet with the Build Alternative. The queues along the ramps at the Northbound Off-Ramp

intersection reduce by up to 63 feet with the Build Alternative. Another major improvement is

the queueing between the study intersections. For example, in the No-Build Alternative the

eastbound movements at NW 69th Terrace would queue back to the Northbound On-Ramp. With

the Build Alternative improvements, the eastbound movement queues will reduce by 701 feet.

7.3. Design Exceptions and Variations Implementation of the proposed improvements will not require any design exceptions or

variations.

7.4. Summary and Recommendations The proposed short term improvements will provide up to a 61% reduction in delay at the study


Design Year 2029.

The proposed short term improvements will also provide a safer transportation facility. Based on

the proposed improvements, it is predicted there will be a reduction of 59 crashes per year within

the study area.

Based upon this analysis, the recommendation is to implement the Build Alternative due to the

improved operations and safety compared to the No-Build Alternative. However, the Build

Alternative will have movements that operate a LOS F by Design Year 2029; so it is

recommended that ultimate improvements be analyzed to address the future traffic demand within

the study area.

8.0 JUSTIFICATION I-75 at SR 26 IOAR

46

8. JUSTIFICATION

8.1. Compliance with FHWA General Requirements The following requirements serve as the primary decision criteria used in approval of interchange

access requests. Responses to each of the Federal Highway Administration (FHWA) two policy

points are provided to show that the proposed modification for the I-75 at SR 26 interchange is

viable based on the conceptual analysis performed to date.

8.1.1. FHWA Policy Point 1

An operational and safety analysis has concluded that the proposed change in access does not

have a significant adverse impact on the safety and operation of the Interstate facility (which

includes mainline lanes, existing, new, or modified ramps, ramp intersections with crossroad) or

on the local street network based on both the current and the planned future traffic projections.

The analysis should, particularly in urbanized areas, include at least the first adjacent existing

or proposed interchange on either side of the proposed change in access (23 CFR 625.2(a),

655.603(d) and 771.111(f)). The crossroads and the local street network, to at least the first

major intersection on either side of the proposed change in access, should be included in this

analysis to the extent necessary to fully evaluate the safety and operational impacts that the

proposed change in access and other transportation improvements may have on the local street

network (23 CFR 625.2(a) and 655.603(d)). Requests for a proposed change in access should

include a description and assessment of the impacts and ability of the proposed changes to safely

and efficiently collect distribute, and accommodate traffic on the Interstate facility, ramps,

intersection of ramps with crossroad, and local street network (23 CFR 625.2(a) and

655.603(d)). Each request should also include a conceptual plan of the type and location of the

signs proposed to support each design alternative (23 U.S.C. 109(d) and 23 CFR 655.603(d)).

An in‐depth operational and safety analysis was conducted to study the impacts of the proposed

improvements at the I-75/SR 26 interchange. Several performance measures were used to

compare the operations of the existing system under No-Build and Build conditions. Key

measures included delay, Level of Service (LOS) and 95th Percentile Queues for existing and

proposed conditions.

Operational analysis conducted for the short term improvements confirm that the proposed

modifications are not expected to have significant adverse impacts on safety or operations at the

I-75/SR 26 interchange and adjacent intersections. When compared to the No-Build Alternative,

the proposed short term improvements will provide up to a 61% reduction in delay at the study


Design Year 2029.

The short term improvements at the study intersections are, also, expected to reduce the number

of collisions at the study intersections, and not have an adverse impact on safety or operations.

8.0 JUSTIFICATION I-75 at SR 26 IOAR

47

Using Crash Modification Factors (CMFs) from the CMF Clearinghouse, a predicted number of

crashes was calculated after the implementation of the improvements. Based on the application

of the CMFs to the study intersections, a 12% reduction in crashes is expected.

The proposed I-75 at SR 26 IOAR will not involve any new mainline access points or change in

the current access locations. The proposed short term improvements are only being applied to the

study intersections. Hence, no analysis was performed for the I-75 mainline, I-75 ramps or

adjacent ramps. Also, the existing signing plan along I-75 and SR 26 will be adequate for the

proposed improvements. A new conceptual signing plan is not required for these improvements.

8.1.2. FHWA Policy Point 2

The proposed access connects to a public road only and will provide for all traffic movements.

Less than “full interchanges” may be considered on a case-by-case basis for applications

requiring special access, such as managed lanes (e.g., transit, HOVs, HOT lanes) or park and

ride lots. The proposed access will be designed to meet or exceed current standards (23 CFR

625.2(a), 625.4(a)(2), and 655.603(d)). In rare instances where all basic movements are not

provided by the proposed design, the report should include a full-interchange option with a

comparison of the operational and safety analyses to the partial-interchange option. The report

should also include the mitigation proposed to compensate for the missing movements, including

wayfinding signage, impacts on local intersections, mitigation of driver expectation leading to

wrong-way movements on ramps, etc. The report should describe whether future provision of a

full interchange is precluded by the proposed design.

The proposed short term improvements to the I-75 at SR 26 interchange and adjacent

intersections will provide full access and cater to all traffic movements from SR 26 to and from

I-75. The proposed modifications are designed to meet current standards for federal-aid projects

on the interstate system and conform to American Association of State Highway and

Transportation Officials (AASHTO) and the FDOT design standards.

9.0 CONCEPTUAL FUNDING PLAN/CONSTRUCTION SCHEDULE I-75 at SR 26 IOAR

48

9. CONCEPTUAL FUNDING PLAN/CONSTRUCTION SCHEDULE

A preliminary cost estimate was prepared for this project as part of the FDOT Safety Study. The

preliminary cost estimate is provided as part of the Safety Study in Appendix A.

The improvements proposed as part of the Build Alternative at the I-75 at SR 26 interchange are

performed under the Programmatic Agreement with FHWA. Therefore, FDOT Central Office

will conduct necessary review and assessment of the justification for the proposed

improvements. The IOAR and design of this project are currently funded under FDOT Work

Program as Financial Project Identification Number (FIN) 437354-1. The Design and

Construction of the improvements are funded for year 2019.

APPENDIX I-75 at SR 26 IOAR

List of Appendices

Appendix A: FDOT Safety Study for SR 26 from NW 75th Street to NW 69th Terrace

Appendix B: Existing Year 2018 Alternative Synchro Operational Analysis

Appendix C: Raw Crash Data

Appendix D: 2019 and 2029 No-Build Alternative Synchro Operational Analysis

Appendix E: 2019 and 2029 Build Alternative Synchro Operational Analysis

Appendix F: Build Concept Figure

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