I may be returning to Campbell, California, and this time I decided to check out the city’s speed survey first. How else could I know what the speed limit signs really mean?
California has strict rules governing city speed limits. Hopefully after seeing what I did you’ll be able to repeat the process with your next destination.
(tl;dr version: Campbell broke the law, a lot.)
Finding the report
The starting point, which you can usually find easily, is the list of speed limits in city ordinances. I found these suspiciously slow, but I was after more than suspicions.
From there you need to find the City Council vote to adopt the speed limits. Follow the historical note “Ord. No. 2194, § 1, 11-17-2015”.
Next stop, the minutes and agendas page. On November 17, 2015 the council unanimously approved a list of non-controversial items including speed limits.
That was the “second reading”. The first reading was two weeks earlier. Download the agenda packet (not minutes) for November 3, 2015. Now you have 114 pages to search. I found the answer starting on page 39.
Ideally a quick Google search would find the document, but this rarely works. California cities often bury speed surveys inside large agenda packets where they won’t be found by search engines. The technical problem is, the files do not have any text in them, only scans of printed pages.
As I have come to expect, the report had a table with a long list of excuses. There are over 70 street segments, most of them with comments explaining why the speed limit should be low.
What the law says
Under California law all changes to speed limits require an engineering and traffic survey.
Additionally, the speed trap law effectively requires all major streets to have speed limits justified by a recent engineering study. Otherwise police can’t use radar to write speeding tickets. You win automatically if the city violates the speed trap law.
Minor streets, legally called “local” streets, can be left at the statutory 25 mph limit or changed based on an engineering study. If a city posts an illegal speed limit on a local street the ticket is not automatically thrown out, but you can tell the judge about the bad speed limit.
By state law speed limits are set close to the actual speed of traffic. This rule is based on the observation that the average driver chooses a safe speed. Maybe more importantly, the average person behind the wheel does a better job than the average person behind a keyboard.
More specifically, the speed limit must be close to the 85th percentile speed of free-flowing traffic. A speed limit in the range 4 mph below to 2 mph above this speed does not need any justification. If an engineering study finds hazardous conditions “not readily apparent” to drivers, the speed limit may be as low as 7 miles per hour below the 85th percentile speed, but this requires documentation.
The details are listed in the California Manual for Setting Speed Limits.
Interpreting the report
The following excerpts from report are typical of the rest. All columns but the last are from the report; the last points out how the recommended speed limit violates state rules.
| No. | Street | Dir | 85th | Limit | Comments | Criticism |
|---|---|---|---|---|---|---|
| 3 | Apricot | EB | 26 | 20 | Narrow street | Prohibited factor |
| 4 | WB | 27 | ||||
| 19 | Budd w/o Winchester | EB | 30 | 25 | Bike route | Readily apparent, > 7 mph reduction |
| 20 | WB | 33 | ||||
| 21 | Burrows | NB | 31 | 25 | Narrow street | Prohibited factor, >7 mph reduction |
| 22 | SB | 33 | ||||
| 23 | Camden | EB | 41 | 35 | High accident frequency | >7 mph reduction |
| 24 | WB | 43 | ||||
| 25 | Campbell w/o Victor | EB | 39 | 35 | No justification for 5 mph reduction | |
| 26 | WB | 40 | ||||
| 39 | Campbell e/o Bascom | EB | 32 | 25 | Residential area with numerous driveways; curved alignment near Midway Street | Readily apparent, prohibited factor |
| 40 | WB | 32 | ||||
| 41 | Capri s/o Hacienda | NB | 31 | 25 | Bike route | Readily apparent |
| 42 | WB | 31 | ||||
| 140 | Winchester s/o Hamilton | NB | 37 | 30 | High pedestrian volumes | Insufficient justification; >7 mph reduction |
| 141 | SB | 39 |
A reduction of 7 mph on Apricot Avenue was justified with the comment “narrow street.” Narrow streets already get lower speed because the measured speed of drivers is slower. Vehicle Code 22358.5 prohibits reducing the speed limit a second time based on factors that already affect operating speed. The engineering study says the limit should be 25.
Apricot is a “local” street, so it’s not a speed trap law violation.
The same excuse was used for Burrows Road, which is subject to the speed trap law. And, a recurring theme, the reduction there is 8 mph below the 85th percentile speed. Only 7 mph is allowed.
The city engineer decided if there were two different speed measurements in opposite directions, the lower would be used. That’s not what the rules say. If opposite direction speeds are more than 5 mph apart, they can be averaged or only the higher used. (Manual § 3.4.2.) Less than 5 mph apart, each stands on its own. There is no provision for picking only the lower.
(This is the reasoning: if the speeds are 39 and 40 it is possible to pick a speed limit that is within -4 to +2 mph of both. The usual rule works. But if the speeds are 34 and 40 it is not possible to pick a limit close to both, so an extra rule is given to resolve the conflict.)
About 20% of city streets break the rule this way.
Many streets have reductions due to pedestrian or bicycle activity, but non-motorized traffic does not automatically justify an extra speed limit reduction:
In areas with high bicycle and pedestrian use, drivers should adjust
their speeds to anticipate both expected and unexpected movements
into moving traffic. These speeds should be reflected in the measured
speeds during a spot speed survey.
The exception is for “high volume traffic generators (vehicular, bicycle or pedestrian) not visible and access points that are not visible to the motorist” (emphasis mine). Also, reductions for non-motorized traffic are a last resort when other measures have failed.
Another excuse is “Numerous driveway turning movements in high-density residential area”. But that’s exactly the sort of thing that drivers are already reacting too when they choose a speed. Traffic is naturally slower in high-density areas, so speed limits will be naturally slower.
In all this analysis I am assuming factual content of the report is honest. I hear San Jose, just to the north, used to send out police to slow traffic before speed surveys. In my area I know of dishonest measurements of both speed and sight distance.
Taking the report at face value, less than half of speed limits comply with state rules.
As I write this I’m sitting in an area where almost no speed limits comply with state rules, so I guess the speed trap law does a little bit of good.
But I’m not going to think those signs have much to do with safety.
The opinions expressed in this post belong to the author and do not necessarily represent those of the National Motorists Association or the NMA Foundation. This content is for informational purposes and is not intended as legal advice. No representations are made regarding the accuracy of this post or the included links.
