Pleasanton’s radar love

Pleasanton, California uses radar to detect the difference between a motor vehicle and a bicycle, adjusting the green phase accordingly. Is this really as “bicycle friendly” as we think it is?

First of all, thank you to the several people who pointed me last week to the numerous stories on Pleasanton’s unique use of microwave technology to determine the difference between cars and trucks and bicycles.

California Vehicle Code 21450.5: Traffic Actuated Signals Detection of Motorcycles and Bicycles

21450. (a) A traffic-actuated signal is an official traffic control signal, as specified in Section 445, that displays one or more of its indications in response to the presence of traffic detected by mechanical, visual, electrical, or other means.

(b) Upon the first placement of a traffic-actuated signal or replacement of the loop detector of a traffic-actuated signal, the traffic-actuated signal shall, to the extent feasible and in conformance with professional traffic engineering practice, be installed and maintained so as to detect lawful bicycle or motorcycle traffic on the roadway.

(c) Cities, counties, and cities and counties shall not be required to comply with the provisions contained in subdivision (b) until the Department of Transportation, in consultation with these entities, has established uniform standards, specifications, and guidelines for the detection of bicycles and motorcycles by traffic-actuated signals and related signal timing.

(d) This section shall remain in effect only until January 1, 2018, and as of that date is repealed, unless a later enacted statute, that is enacted before January 1, 2018, deletes or extends that date.

Radar technology to detect vehicles to trigger traffic lights has been in regular use for at least 20 years. As I reported last year, Pleasanton’s innovation is their use of software to identify bicyclists and give us a longer green light so we have time to cross the intersection.

Pleasanton’s efforts are in response to California AB 1581, which mandates that all new traffic signals must detect bicycles and motorcycles. A Caltrans committee established the technical standards defining what constitutes compliance with AB 1581, and the California Association of Bicycle Organizations pushed through minimum crossing times for cyclists into this requirement. What good is detecting cyclists, after all, if we don’t have time to cross the intersection? All new traffic signals in California must, by law give enough time for bicyclists to cross an intersection.

Several cities in traffic-congested Southern California strongly oppose the bike detection and timing requirements because adding additional green light time to accommodate cyclists will make traffic even worse than it is now. While a few transportation agencies either ignore CVC 21450.5 or play a passive aggressive game by claiming compliance when, in fact, they don’t have compliant intersections, a couple of cities have openly registered their outright refusal to comply with the law, essentially inviting bike advocates to fight this law out in the courts.

Pleasanton also would like to avoid the longer green phases required by law, so when MS SEDCO demonstrated their bike and pedestrian detecting microwave sensors in the Spring of 2010, Pleasanton jumped at the chance to trial their equipment.

The city can retain their auto-centric traffic engineering, comply with state law and receive national acclaim for their bike friendly traffic signal work!

For details on Pleasanton’s radar detection, see: Microwaves, bikes, and traffic lights.

Trivia: That perennial driving song “Radar Love” was written and performed by a DUTCH band.


  1. I’m fine with the idea of the light not giving me, as a cyclist, any extra time. I’d like to think some of those lights are timed very specifically to create the ideal traffic flow, and I’m not interested in messing that up.

  2. radar love…awesome…truly one of the great rock n’ roll & driving songs…the band ‘golden earing’ celebrates their  50th anniversary this summer with the euro postal service issuing a stamp in their honor…
    …despite other hits, particularly in europe, this song alone assures them of lasting fame…

    …okay, now…what was this about traffic lights & pleasanton ???…

  3. I had no idea about the postage stamp or even that Golden Earring is still around!

    I’ve had “Radar Love” thrumming through my head all weekend. There are certainly worse earworms to fall victim to.

  4. “adding additional green light time to accommodate cyclists will make traffic even worse than it is now”

    I suspect this claim is overblown.  We’re only talking about those on-demand signals that serve relatively low volumes of traffic (like a minor collector street crossing an arterial).

    In those locations, the arterial has the vast majority of the green time.  If you add enough minimum green time for a cyclist to cross, the arterial still gets the vast majority of the green time.

  5. In my busiest left turn, I generally get through the intersection as quick as the motorists. Well, except for the few that run the red from the left hand LT lane. I suppose someday I will have to be a witness and I hope it isn’t anyone I know. I agree this fixes a nonexistent problem since even a slow cyclist can easily enter the intersection on green which is the requirement. Assertive riding covers any remaining danger.

  6. ..the two “kids” (guitar & bass – 13 & 15 years old) who started the band are still playing with the “new” singer & drummer who joined in 1967 & 1970…

    golden earring has used various sidemen both live & in the studio throughout the years but the 4 guys who had the hit radar love in 1973 are still playing together…

    …& you are quite correct, sir, as i have fallen victim to the same delightful malady…

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