Setting Speed Zones
Oregon Transportation Safety Conference
October 2019
How are speeds set in Oregon?Some by state statute
2
• 15 mph Alleys or Narrow residential roadways (less than 18’ wide)
• 20 mph Business district, school zones and on some residential roads.
• 25 mph Residential districts, public parks and ocean shores
• 55 mph Rural highways (and not posted elsewhere)
• 60 mph trucks on most interstates and some rural highways (65 mph on some interstates and rural highways)
• 65 mph Passenger vehicles, light trucks on interstate highways (70 mph on some Interstates)
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Local road authorities can set speeds on low volume local roads
Set Emergency and Temporary speed zones
How are Speeds set in Oregon?Some by Local Agencies
15 M
PH
20 M
PH
25 M
PH Need Investigation to Determine 55
MPH
65 M
PH
70 M
PH
Statutory Statutory
*Designated may be any speed or if roadway does not meet statutory requirements
How are Speeds set in Oregon?Some by Designating Speeds (the alternative to Statutory)
Designated Speeds
Where statutory speeds don’t fit the road or the land uses
When the statutory speed is greater than is safe or reasonable
Requires Engineering Investigation of conditions
5
Request Investigation & Recommendation
State Traffic-Roadway
Engineer Action
6
Speed Zone Investigation
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Collected, compiled, analyzed:
Roadside characterTraffic mix & volume
Crash dataRoadway measurements
Travel Speeds
Concurrence on Local Jurisdiction's Roadways
State Traffic Roadway Engineer
Local Jurisdiction
Concurs/or not
Option to take to SZRP
SZRP Makes final decision
Speed Zone Order
Does not concur
Reconsider
Concurs
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Speed Zone Review Panel
Representatives from City, County, Safety, Enforcement and ODOT
Hears disputed speed zone cases
Makes final decision on speed zones
10
Objective process
Statewide consistency
Minimize Speed Variance
Local options
Investigate “the middle”
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Travel Speed directly impacts mobility (time of travel)
Travel Speed directly impacts Safety
New methodology -Our task is to set Reasonable and Safe Speeds
Speed setting practices are often political
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Mobility was the highest value, increasing travel speeds to get there faster
Roads were built to move motor vehicles more quickly
Where were we in the past?
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Local road authorities are desiring to slow speeds to meet community values
We have many other users besides motor vehicles now
Where are we going in the future?
Set Context based on Land Use
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Set Speeds for Context and Function
15
Proposed Target Posted SpeedsContext > Urban
Core/CBDUrban Mix Suburban
Commercial and Residential
Suburban Fringe
RoadwayClass
Arterial 20‐25Low
25‐30Med Low
30‐35Med High
35‐45High
Collector 20‐25Low
25‐30Med Low
25‐35Med
30‐40Med High
Local 20‐25Low
20‐25Low
25‐35Med
25‐35Med
An alternative speed using 50th
percentile can be used if:• 50th percentile speed is more than 5
mph greater than range• Context is inconsistent• Limited Access Facility
Speed can vary 10 mph below 50th if:• Average Crash rate exceeds 1.5
times average for functional class• More than one F&A in 3 yrs• Meets definition of residence
district
Proposed Target Posted SpeedsContext >
Roadway
Rural Highways Rural Communities
State Highways or Non‐state Arterials
85th percentile+/‐5 mph
50th percentile +/‐5 mph
Non‐State collectors or locals
50th percentile +/‐5 mph
50th percentile +/‐5 mph
Rural Communities (unincorporated communities) - within 10 mph of 50th
percentile speed:• Urban character• Meets Business or Residence District• DLCD Unincorporated Community
State Highways or Arterial; and Non-arterial County Road.+/-10 mph if:• crash rate 1.5 times statewide • more than one F&A class• limited sight distance crashes
Why is considering other methods important?
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• Reduce Crashes (a small reduction in travel speed results in a reduction of severe crashes)
• Improve Comfort and Consideration of Active Modes
• Increase Community Livability
• Transitioning to a more context based method
Thank you!19
Active Trans Options
Reasonable and Safe
All Users
Compliance
Safety
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