Bill Could Make it Easier for Cities to Lower Speed Limits

Image from Road Safety Facts from WHO
Image from Road Safety Facts from WHO

Research consistently shows that speeding vehicles greatly increase safety risks, for people in cars as well as for pedestrians around them. The faster a vehicle goes, the longer it takes to come to a stop. Faster speeds lead to higher likelihood of a crash, and the higher the speed of a crash, the higher the likelihood of serious injuries and fatalities. The chart above, from a World Health Organization report on traffic injury prevention, shows the relationship between speed and risk to pedestrians.

But cities in California have been hamstrung when it comes to lowering speed limits.

State authorities, to prevent local jurisdictions from creating speed traps—where speed limits are abruptly lowered so that local police can charge drivers for speeding and thus make money for a municipality—have severely restricted the way speed limits can be set in California. That has led to some unexpected and negative consequences for safety.

If a town wants to lower a speed limit, for example as part of an effort to make their downtown safer, it must conduct a speed survey of vehicles currently driving on the road. Then, says the law, it must set the speed to match however fast 85 percent of the drivers go. There is no accounting for either design or safety, except for one point: if an engineering survey were to show a need for a lower speed limit than that 85 percent rule would call for, then the results could be rounded downward.

One result of the kind of thinking this rule produces is that engineers have a hard time understanding that designing for slower speeds is a thing—that, for example, narrowing lanes or adding bulbouts could lead to safer outcomes for all road users.

And it has led municipalities to avoid even trying to lower speed limits. If most people are speeding in an area, the results of the required speed survey may force them to raise the speed limit instead. Nevertheless, cities are required to regularly update their speed limits, and must do so if they wish to enforce the limits. Combined with engineers’ tendencies to overdesign streets for “safety,” with wide lanes and clear sight-lines, California has witnessed a steady increase in speed limits over time.

This is pretty much the opposite outcome from what safe streets proponents would like to see.

Or course, speed limits, which after all are no more than numbers on signs, are not the complete solution to making streets safer. But they are one important tool, which cities are currently not able to deploy effectively.

That may change, if a bill by Assemblymember Laura Friedman (D-Glendale) is successful.

Glendale, says Friedman, has more than its share of pedestrian crashes and injuries, and the city has been dealing with the problems of street racing as well. Looking around for inspiration, she found L.A.’s Vision Zero efforts that create a framework for reducing casualties. Among its recommendations are to look at the actual crashes on a street or road or network and focus efforts on those areas that have the most serious problems.

Her bill would add only a few words to current law, creating another exception to the 85 percent rule. That is, under A.B. 2363, a local jurisdiction could use information from a collision survey to help it lower a speed limit. So if an area is found to have a high crash rate, an exception can be made.

Her staffers say Friedman is working with a number of organizations, including the city of L.A., the L.A. County Bicycle Coalition, CalBike, California Walks, and the CHP, to come up with a definition or guidance on what such a collision survey would entail.

Rock Miller, an engineer who has been working to change 85 percentile rule for a number of years, says the bill would need further amendments for it to work. For one thing, there is no provision for lowering the speed limit farther than just rounding down from the 85th percentile results.

Miller says that opposition to loosening speed limit requirements has been intense. A time-limited pilot program could get more support, and could be studied for effectiveness as well, he said. He also thinks it worth considering for the legislature just to direct Caltrans or the CAMUTCD, which is currently tasked with writing speed limit rules, to figure it out themselves, as they have said they have no authority to make changes.

At least Assemblymember Friedman has started the conversation. Let’s hope it leads to slower speeds and safer streets.

82 thoughts on Bill Could Make it Easier for Cities to Lower Speed Limits

  1. …or the city could simply enforce the new speed limit until the street can be re-engineered to properly reflect context. That would save lives that would otherwise be lost to speeding motorists who ignore the law.

  2. I am interested ONLY in realities, things that actually work.

    For example: If a city wants the slowest 85% of the drivers to be at or below 25 mph, then it MUST design or re-design the street so the slowest 85% of the drivers feel safe and comfortable only at speeds up to about 25 mph. THAT is extremely effective with a minimum of 85% voluntary compliance, speeding by more than a few mph disappears, enforcement becomes virtually unnecessary and any that is done is never a for-profit racket.

    James C. Walker, National Motorists Association

  3. Children riding bikes on the street that they live on, as they rightfully can and should. Driver speeds and strikes a child.

    Cop: “You hit the child.”

    NMA: “It’s not the drivers fault because the street should’ve been designed differently.”

    In America there are over 37000 deaths per year due to automobile accidents, and hundreds of thousands of non-fatal accidents per year. Speeding is a major factor. Wake up.

  4. Correct. And far too many venues just post lower limits with no engineering changes – knowing for certain the speeds won’t change but they have other reason$$$$$$$$$ to do it.

    James C. Walker, National Motorists Association

  5. the person driving 25 is more likely to get rear ended by another driver.

  6. yellow speed limits signs for sharp curves are advisory and not legally enforceable.

  7. this reporting distorts the current legal situation. Cities and counties across california can set speed limits to whatever they want on their roads by passing law to make it so. what they can’t dp is change speed limits on state highways that way. As far as state highways go, they do the survey every 5-7 years, find the 85th, and round to the nearest 5mph increment, currently. Also please recognize that chart above is in KPH not MPH.

  8. Revise Section 2B.13 of the Manual on Uniform Traffic Control Devices so that
    the factors currently listed as optional for all engineering studies are required,
    require that an expert system such as USLIMITS2 be used as a validation tool, and
    remove the guidance that speed limits in speed zones should be within 5 mph of the
    85th percentile speed. (H-17-27)
    Revise Section 2B.13 of the Manual on Uniform Traffic Control Devices to, at a
    minimum, incorporate the safe system approach for urban roads to strengthen
    protection for vulnerable road users. (H-17-28)
    Work with the National Highway Traffic Safety Administration to update the Speed
    Enforcement Camera Systems Operational Guidelines to reflect the latest
    automated speed enforcement (ASE) technologies and operating practices, and
    promote the updated guidelines among ASE program administrators. (H-17-29)
    Work with the National Highway Traffic Safety Administration to assess the
    effectiveness of point-to-point speed enforcement in the United States and, based
    on the results of that assessment, update the Speed Enforcement Camera Systems
    Operational Guidelines, as appropriate. (H-17-30)

  9. In a perfect world where everyone obeyed all the rules all the time, many things would be different. The view of the NMA and most engineers is that we have to deal with the real world situations with real world solutions. Hoping for perfect compliance with posted limits set far below the speeds most drivers find to be safe and comfortable is a totally lost cause. Enforcing those low limits with anything short of 24/7/365 methods will fail – and the only practical result of lesser enforcement will be revenue collections, not increased safety or significantly reduced speeds most of the time.

    If you talk to most experienced police officers, they do NOT want the public to try to control the driving behavior of other drivers – it doesn’t work and can lead to aggressive driving or even road rage at times. If a city really wants most drivers to be at speeds of about 25 mph or less, then the street must be re-engineered so that 85% of the drivers who used to feel safe and comfortable at speeds up to about 35 mph now feel safe and comfortable only at speeds up to about 25 mph.

    I have studied these issue for over 50 years and talk regularly with some nationally-known experts in the field.

    James C. Walker, National Motorists Association

  10. You are giving excuses for bad driving; those people tailgating, etc. should not be driving if they have no self control… it would be better to get them off the roads.

  11. If you want the safety that can come with slower actual speeds, then re-engineer the streets to achieve that result.

    James C. Walker, National Motorists Association

  12. Re-engineer the streets, don’t use predatory for-profit speed traps operated often enough to make profits, but not 24/7/365 to actually reduce speeds.

    James C. Walker, National Motorists Association

  13. And may well cause tailgating, aggressive driving, passing where not safe, and even road rage. If the 85th percentile speed is 36 but authorities want it to be about 25, the only effective answer is to re-engineer the street so that 85% of the drivers now feel safe and comfortable only at speeds up to about 25 mph. This is effective and eliminates the chances of for-profit speed traps.

    James C. Walker, National Motorists Association

  14. Most streets designed in the past 50 +- years have been poorly designed, in that they encourage speeding. It will take many years, and multi-millions of dollars to fix that, but lowering speed limits now can begin to make our streets safer.

  15. This is why it is more important now to improve the safety of pedestrians, bicyclist, etc, who are the ones in danger from speeding cars and generally bad drivers.

  16. Drivers are not the ones getting hurt/killed on city streets…. it is pedestrians, bicyclists, animals; therefore, the speeds should relate to their safety first rather than drivers’.

  17. The person driving 25 will slow the other drivers down and is much less likely to run over a person or animal. The worst ‘crashes’ are the ones which involve pedestrians, animals, bicyclists; hence slowing everyone down is a benefit.

  18. Having at most one lane in each direction helps cure the problem of speeding cars passing others that are driving at a safe speed.

  19. The rule is there to prevent speed traps and but not much different than ensuring that red light caveats have a consultant yellow light duration.

    I don’t see this as a big deal given them number of tools available… Road diet, narrower lanes, bulbouts, even on demand crosswalk lights hunt to dinner to be more careful. Install a few of these, and do a new speed analysis. If we still have a problem, then let’s talk.

  20. Nine years ago then Asm. Paul Krekorian tried to loosen the 85th percentile rule and got slammed by AAA and Assembly leadership. Mike Gatto had more success with a more modest bill. I imagine many of the same groups are lining up this year.

    Here’s my (hastily written and with some typos) coverage of the hearing where Krekorian’s bill was shot down from 2009:

  21. The NMA opposes things which do not work and can be abused in for-profit money grab rackets. One of the most obvious of these rackets are speed limits posted well below the actual 85th percentile speeds – and then enforced with enough frequency to make a lot of profits, but not frequent enough to reduce the actual speeds by enough to matter for safety overall.

    If people care about the viability of economic areas that have high rates of commuters and visitors arriving in cars and trucks, then congestion is a real issue. Diversion which degrades safety area-wide is also a real issue. Make the 4 or 6 lane collector or arterial congested enough, and some drivers will divert to roughly parallel 2 lane streets that were never designed for the volume and attempted speeds of frustrated commuters and shoppers. A NJ city is trying to make it illegal to travel their minor streets to go around congestion.

    These are both real issues, and it is surprising that anyone who is not in the revenue stream from for-profit rackets doesn’t understand them.

    James C. Walker, National Motorists Association

  22. Oh OK. 40,000 is perfectly good because it used to worse. Got it.

    The NMA strongly supports throwing up flak to block any action that will slightly inconvenience drivers in any way even if that means killing people. You promote what are otherwise smart policies (like using sound engineering and road design) as ways to stall or defeat small steps to improve the safety and livability of street design because you know that those kinds of improvements are expensive, take huge amounts of time, and are easily stopped when proposed because they will “cause congestion”. Better yet, you have convinced yourself you are acting righteously by only pushing “for sound policies” even though they manage to perfectly align with your general principle that people in cars should be able to drive as fast as possible at all times and if someone gets in your way it’s their fault they died. Thanks!

  23. If the actual 85th percentile speed is 36, then up to 36 mph is likely safe for virtually all drivers (excluding perhaps a Model T).

    Your thought on a sharp curve is VERY important, and often made more dangerous by under-posting limits. If this street with an 85th speed of 36 has a curve that should not be taken at more than 25, then it does need a curve warning sign and an advisory limit of 25 to protect the unfamiliar driver. If the street is posted at 35, it would get the warning sign and 25 advisory limit. If the street is posted at 25, it would not. So the unfamiliar driver could easily get “caught out” by the sharp curve, the regular commuters would know about it from experience.

    James C. Walker, National Motorists Association

  24. My point is *why* there is a posted speed sign at all. You are on a single track and think everyone is against you. We have speed limit signs at sharp turns for a reason. The unfamiliar driver would otherwise have no reason to know what the 85th percentile *was* and might well head off into the underbrush.

  25. If the 85th percentile speed is 36 and the posted limit is 25, the unfamiliar driver who sticks to 25 has a higher risk of crashing than the drivers at about 36. It happens that the drivers at about the actual 85th percentile speeds have the lowest statistical risks to be any kind of a crash.

    James C. Walker, National Motorists Association

  26. There is another reason. To advise the motorist unfamiliar with the area what the safe speed is. This is for the motorist’s own safety as well as the pedestrians he may otherwise harm.

  27. The fatality rate data counts pedestrians, cyclists, and occupants of vehicles.

    James C. Walker, National Motorists Association

  28. It rose a bit in 2015 & 2016, early estimates of 2017 say it went back down a bit. We drive over 3 trillion miles a year at fatality rates about 75% safer than when I got my first license in 1960.

    The NMA strongly supports improvements based on sound engineering, better driver training, and enforcement aimed at the genuinely hazardous drivers. We strongly oppose enforcement for profits because enforcement for profits is 100% wrong, 100% of the time.

    James C. Walker, National Motorists Association

  29. If the posted limits had any significant effect on the actual travel speeds, yours would be a good argument. But in the absence of something closet to 24/7/365 enforcement that no community can afford – they don’t. Limits set well below the actual 85th percentile approach speeds have only one purpose – for profit speed traps that no one should ever tolerate, because enforcement for profits is 100% wrong 100% of the time.

    James C. Walker, National Motorists Association

  30. It is true that street design probably has a larger impact on actual driving speeds than posted speed limits. But that does not mean that posted limits should not reflect either the roadway design or best opinion of roadway designers and local officials. Posted limits exist to create an enforceable standard. Arguing that we should not post applicable limits to roadways is saying that there should not be any traffic enforcement at all.

  31. Please bear in mind that over 40,000 people were killed in traffic collisions in the US in 2016 and that number has been rising in recent years by significant percentages. The reason that number is lower than in decades past is due to a large number of rules and improvements that have generally been fought tooth and nail by the auto industry including your association.

  32. Please bear in mind that driving today is incredibly safe compared to decades past. The fatality rate is about 1.2 fatalities per 100 million vehicle miles traveled, so if you are in a car for about 15,000 miles a year – you will be involved in a crash with a fatality about once in every 5,500 years.

    James C. Walker, National Motorists Association

  33. If the road is actually reconfigured for a lower speed of example 25 mph, then leaving signs for 35 will NOT have many cars at 35 because most drivers will no longer feel safe and comfortable at speeds above about 25.

    James C. Walker, National Motorists Association

  34. Setting posted limits below the actual 85th percentile speeds does NOT reduce the actual travel speeds or improve safety. Indeed it may reduce safety by causing more speed variance as a tiny percent of drivers obey the improper limits, but most do not.

    If a city wants to lower the actual travel speeds, it must re-engineer the roadway so that (for example) about 85% of the drivers who formerly felt safe and comfortable at speeds up to 35 mph now feel safe and comfortable only at speeds up to about 25 mph. This is effective for travel speeds, it costs money and kills speed trap enforcement, and it may have other negative effects if drivers divert to smaller parallel streets to avoid congestion.

    James C. Walker, National Motorists Association

  35. Agencies have been allowed to lower speed limits if they redesign and conduct a new speed survey. With the State making many millions of dollars available for safe street improvements, it would be much better to just focus on getting agencies to put the existing tools to use by redesigning streets with speed problems for a more appropriate speed than just arbitrarily lowering the limit, especially if speed cameras remain out of reach.

  36. “…
    Miller says that opposition to loosening speed limit requirements has been intense.”

    It would be helpful to know who are main anti- speed-limit opposition. Name names, not just organizations. This is personal. It should be personal. Based on the millions of traffic deaths and horrifying injuries, nationally and world wide, there is more blood on their hands than on any movement in existence.

  37. The most disturbing aspect to me is that agencies refuse to reduce speed limits on streets that have been reconfigured for a lower design speed. So thousands to millions are spent on calming a street, but the speed limit remains the same. There is no justification in case law or legislation for this, but it continues. We just need to recognize that the 85% principle is responsible for thousands of deaths, and end it.

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