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![Contact Information Sgt. Lance R. Cook Michigan State Police Traffic Services Section 4000 Collins Road Lansing, MI 48909 (517) 336-6660 [email_address] Mr. Jim Walker JCW Consulting 2050 Camelot Road Ann Arbor, MI 48104 (734) 668-7842 [email_address]](https://image.slidesharecdn.com/settingmunicipalspeedlimits-12620966964126-phpapp01/85/Setting-Municipal-Speed-Limits-30-320.jpg)
Setting Municipal Speed Limits
- 1. Setting Municipal SpeedLimits: Compliance with 2006 PA 85 2007 ITE Michigan Section Technical Session December 6, 2007 Sgt. Lance R. Cook Mr. Jim Walker Michigan State Police JCW Consulting Traffic Services Section
- 2. Background Information HowWe Arrived at Where We Are Today
- 3. Background Information Trafficengineering—especially setting speed limits—is largely counterintuitive Public and elected officials do not understand—tend to want solutions that provide a false sense of security over solutions that actually create safer driving Traffic engineers are often threatened or coerced into political solutions for perceived problems
- 4. Background Information Recurringissues with speed limits Gravel roads State and county roads inside cities Residence and business districts Definitions stretched or misapplied Attempts to establish 15 mph speed limits Road rage and aggressive driving Township involvement
- 5. Background Information 2006PA 19 (HB 5104) Rep. Caswell 2006 PA 85 (HB 5240) Rep. Palmer 2006 PA 86 (HB 5241) Rep. Palmer
- 6. Background Information Newlaws helped to raise public awareness of the problems New laws give traffic engineers greater ability to make good decisions for safety while reducing or eliminating ability to make decisions based solely on politics
- 7. Section 1 LawsAuthorizing the Establishment of Speed Limits by Municipalities
- 8. Authority for MunicipalSpeed Limits MCL 257.606(1)(k) Increase prima facie speed limits as authorized in this act MCL 257.608 Establish MMUTCD by MSP and MDOT MCL 257.610(a) Apply MMUTCD to local ordinances and related traffic control devices MCL 257.610(b) Authority of MDOT to withhold gas tax money for noncompliance
- 9. Authority for MunicipalSpeed Limits (continued) MCL 257.627(2)(a) Prima facie speed limit of 25 mph in Business District as defined in MCL 257.5 MCL 257.627(2)(b) Prima facie speed limit of 25 mph in public park MCL 257.627(2)(c) Prima facie speed limit of 25 mph within platted subdivision per MCL 560.101 et seq. or condominium complex per MCL 559.101 et seq.
- 10. Authority for MunicipalSpeed Limits (continued) MCL 257.627(2)(d) Prima facie speed limit of 25 mph for 60+ vehicular access points within ½ mile MCL 257.627(2)(e) Prima facie speed limit of 35 mph for 45-59 vehicular access points within ½ mile MCL 257.627(2)(f) Prima facie speed limit of 45 mph for 30-44 vehicular access points within ½ mile
- 11. Authority for MunicipalSpeed Limits (continued) MCL 257.627(3) Speed limits per subsection (2) are prima facie MCL 257.627(10) Requires speed limits established per this section to be properly posted or default to 55 mph per 628(1) MCL 257.627(12) Allows a traffic and engineering investigation MCL 257.627(13) Defines vehicular access point as driveway or intersecting roadway
- 12. Authority for MunicipalSpeed Limits (continued) MCL 257.629(1) Allows for establishment or increase of speed limits on municipal streets per the following limitations: (a) Increases within business district require designation as a through street (b) Increases require adequate signs (c) Speed limits established outside of business districts must be consistent with limits established in MCL 257.627(2)
- 13. Authority for MunicipalSpeed Limits (continued) MCL 257.629(2) Gives MDOT authority to establish speed limits on state roads within municipal limits MCL 257.629(3) Allows for prima facie speed limit of 15 mph in public parks MCL 257.629(4) Allows for prima facie speed limit of 25 mph on streets adjacent to public park or playground MCL 257.629(7) Defines local authority as a city or village except for 257.629(4)
- 14. Authority for MunicipalSpeed Limits (continued) MCL 257.951(1) Allows MSP to promulgate Uniform Traffic Code for Cities, Townships, and Villages (UTC), and allows municipalities to adopt by reference Subservient to MVC; any conflicts with MVC or other state law render UTC section null and void
- 15. Section 2 Mechanismfor the Establishment of Speed Limits by Municipalities
- 16. Mechanism for Establishmentof Municipal Speed Limits MCL 257.610 requires municipal traffic control devices to conform to MMUTCD MMUTCD 2B.13 requires an engineering study made in accordance with established traffic engineering principles Warrants for speed limits from MMUTCD include: Within 5 mph of 85 th percentile speed of free-flowing traffic May consider other factors
- 17. Mechanism for Establishmentof Municipal Speed Limits (continued) UTC R 28.1126 Rule 126 requires all duties of traffic engineer to be in accordance with standard and accepted engineering practices as found in the ITE Traffic Engineering Handbook, 5 th Edition UTC R 28.1153 Rule 153 requires all traffic control orders to be in accordance with standard and accepted engineering practices as adopted in R 28.1126
- 18. Mechanism for Establishmentof Municipal Speed Limits (continued) Primary warrants for speed limits from ITE Handbook 5 th Edition include 85 th percentile of free-flowing traffic and upper limit of 10 mph pace
- 19. Mechanism for Establishmentof Municipal Speed Limits (continued) R 28.1153 Rule 153(1) requires a Traffic Control Order to be filed with municipal clerk and adequate signs erected to become effective R 28.1153 Rule 153(2) allows temporary TCOs for 90 days R 28.1153 Rule 153(7) Temporary TCOs must also conform to ITE standards Rule 153 language intended by MSP to apply 257.628 TCO process to municipal TCOs
- 20. Section 3 CaseStudies and Effects of Proper and Improper Posting of Speed Limits
- 21. Proper v. ImproperPosting
- 22. Proper v. ImproperPosting
- 23. Proper v. ImproperPosting
- 24. Proper v. ImproperPosting
- 25. Proper v. ImproperPosting
- 26. Proper v. ImproperPosting
- 27. Resources Manuals andInternet Links
- 28.
- 29. Group Discussion Questionsand Comments
- 30. Contact Information Sgt.Lance R. Cook Michigan State Police Traffic Services Section 4000 Collins Road Lansing, MI 48909 (517) 336-6660 [email_address] Mr. Jim Walker JCW Consulting 2050 Camelot Road Ann Arbor, MI 48104 (734) 668-7842 [email_address]
Editor's Notes
- #2 Brief introduction of speakers and overview of presentation
- #4 Problem can be much worse in areas where the police chief is the de facto traffic engineer, with no technical training in the discipline. A whole generation has been brought up believing the 1974 NHTSA propaganda during the counterproductive NMSL era Many city engineers feel they have to please their mayor or city council, even to the point of completely ignoring proper engineering standards.
- #5 Bills introduced almost every legislative session attempting to “fix” one or more of the problems. Counterintuitive--many solutions did/would make some problems worse Oakland County gravel roads mislabeled as residence districts in past years (definitions now changed by PA85) Downtown designations as business districts by virtue of sign East Lansing lawsuit Public misperception of causes of road rage/aggressive driving McNitt Act—townships don’t own or control roads, yet legislature recently included them in the process
- #6 PA 19 Raised truck speeds to 60 mph on freeways with 70 mph speed limit for cars (political influence forced 60 instead of 65 in original bill) PA 85 Repealed definition of Residence District, amended definition of Business District, and established access point formula PA 86 Amended Pupil Transportation Act to match changes to MVC for School Bus speed limits Legislators approached MSP after repeated opposition to previous bills to work for a solution to many of the issues MSP, MDOT, NMA, and other groups educated a small group of legislators, including Caswell and Palmer on engineering and safety There were several compromises made, but these three laws are a huge step in the right direction PA85 provides a way for township officials to “opt out” of speed limits, a good choice for many of them for political cover.
- #7 Nationwide, the motoring public is becoming more educated about how speed limits are set. The internet has made unbiased traffic safety engineering studies widely available, so public can see what is being done wrong. Instead of attacking the police officer’s credibility, the RADAR unit, or the circumstances of the individual stop, people are beginning to attack improperly posted speed limits. One court case has the potential to expose an entire speed limit as invalid and another one is probably coming soon with a well known engineer. Can result in a domino effect, exposing a municipality’s entire system as weak or invalid (Lansing, Grand Ledge, Ann Arbor, etc.). The city of Chelsea looked at the new law, agreed it was in effect, and did proper TCOs under 257.951 to re-set proper limits on many of their major collectors and arterials that closely reflect 85 th percentile speeds.
- #10 Most of the speed limits over next several slides apply to state, county, or municipal roads unless otherwise mentioned. Discuss repeal of definition of Residence District and changes to definition of Business District.
- #11 Applies to state, county, or municipal roads
- #12 Applies to state, county, or municipal roads. Subsection (11) refers to MCL 257.628(1), and is specific to county and state roads speed limits as established by the TCO process. Discuss general speed limit from MCL 257.628(1). Discuss studies leading up to access point formula -- compared actual 85 th percentile speeds to actual access point counts. While there are some exceptions on some roads, the formula sets many roads at or very close to the 85 th percentile speed of free flowing traffic under good conditions.
- #13 Discuss changes to definition of business district. Discuss the term adequate sign. Reinforce access point formula in MCL 257.627(2).
- #14 Discuss township authority for county roads.
- #15 Discuss relationship of MVC, UTC, and MMUTCD MUNIPALITIES CAN GAIN AUTHORITY TO DO TCOs by adopting 257.951, but the UTC reinforces that the traffic and engineering studies must be done according to standard and accepted engineering practices in the ITE manual.
- #17 Describe other factors. Discuss relationship of other factors to 85 th percentile and problem with double counting of other factors. Other factors should ONLY be used when they are not readily apparent to most drivers. Obvious factors like parked cars, common bike and pedestrian traffic, narrow lanes, visible curves, etc. are already taken into account in the 85 th percentile speeds chosen. Hidden hazards or brief parts of a segment that should be slower than the rest of a long segment should use proper warning signs and advisory speeds. It is incorrect to post a 2 mile stretch of road with the conservative design speed needed for just the 150 yard hazard in the center.
- #18 Discuss police chief as de facto traffic engineer if none appointed. Discuss some issues with various municipalities, i.e. Auburn Hills, Grand Ledge, Ann Arbor, Lansing, etc. Properly done, it should not be acceptable to post speed limits at the 4 th or 22 nd percentile speed of free flowing traffic under good conditions. If the engineer uses proper practices, posted limits will define the normal, prudent and safe driving practices of the majority of drivers as legal, rather than defining 67% or 82% or 96% of the drivers as in violation of an improperly low limit.
- #20 Discuss lack of mechanism to adjust speed limits if UTC not adopted.
- #22 The drivers at the least risk of having a crash tend to be in the 60 th to 90 th percentile speed ranges, but these drivers are above the posted speed limit in a great percentage of cases. Why is it OK for anyone to define the safest drivers as in violators subject to very large financial penalties from the courts and their insurance companies? Safe drivers should be allowed to proceed without fear of sanctions.
- #25 Normal Distribution or Bell Curve Note that one standard deviation above the mean closely approximates 85 th percentile with 68% of drivers within one standard deviation of mean. Note that a 16 th percentile speed posted limit is the “virtual inverse” of proper procedure and defines the entire 68% center of the bell curve as illegal, a practice that is difficult to defend in engineering terms. Yet, this is what many politicians want to happen, to satisfy citizens that know absolutely nothing about the science of traffic safety engineering.
- #26 Freeway raised from 55 mph to 70 mph. Note tightening of distribution around mean. This section of I-69 in Flint now flows much more smoothly, with better lane courtesy.
- #27 Speed limit raised from 25 mph to 35 mph. Note almost no change in distribution, except now 90% of drivers are within 5 mph of posted limit, compared to almost 100% in violation under previous limit. No posted limit that defines 80% or 90+% of normal, safe drivers as violators can ever command respect. These practices degrade the overall respect for traffic laws and for law enforcement officers in general – which is a very poor practice for society.