Golden Gate bike speed limit update

 

 

Golden Gate Bridge officials propose 15 MPH bike speed limit, with 5 MPH limit when passing.

 

 

You might remember the hub bub last April when Alta Planning proposed a 10 MPH bicycle speed limit on the Golden Gate Bridge. When cyclists showed up at the subsequent Golden Gate board meeting to complain, the board members said they would reconsider the plan.

Bridge officials promised to have another proposal in July 2011, but they sent up this trial balloon of a 15 MPH speed limit for bicycles and 5 MPH limit when passing pedestrians .

The Golden Gate Bridge has sidewalks on either side of the bridge. Fast recreational enthusiasts and commuters share the narrow east span with tourists on rental bikes and walkers. The local enthusiasts and commuters just want to get to the other side fast, while the tourists (understandably) want to enjoy the view. They dawdle. They stop. They soak in that wonderful Golden Gate vibe.

If you have trail conflicts between walkers and cyclists in your neighborhood, multiply that by about a hundred on the GGB. On a weekend day, about 10,000 walkers and nearly 5,000 cyclists use the GGB sidewalks. Unlike most busy paths, however, path users cannot just step off of the trail into the adjoining grass — on the Bridge sidewalks, you have Highway 1 traffic hurtling past at 45 MPH on one side, while the Pacific ocean churns through the Golden Gate 270 feet below on the other side.

Bridge officials tell us, however, that the injury causing crashes are typically head on collisions between local enthusiasts. Mulligan told the Chron that somebody leaves the Bridge sidewalks on an ambulance about once a month.

More foot and bike traffic than capacity.

Because the west (Pacific) facing sidewalk is now closed due to construction, the speed limit is completely moot. Bicycle riders and walkers currently share the extremely congested narrow walkway on the east (Bay) side of the Bridge. Nobody is travelling greater than 15 MPH, especially on the weekends. There is currently significant conflict between pedestrians and bikes on the GGB, but the proposed speed limits won’t help because they don’t matter.

When the west sidewalk re-opens to bicycle traffic in September 2011, the sidewalks go back to the GGB usual scheduling rules for bicycles and pedestrians. Walkers are never allowed on the west sidewalk, and during times of busier bike traffic (i.e. weekday afternoons and all day on holidays and weekends), bikes are allowed only on the west sidewalk.

My opinion and your opinions.

The justification for a 15 MPH speed limit? Because that’s what everybody else apparently does. “15 mph is a common speed limit on many multi-use paths,” says GGB General Manager Denis Mulligan in the Chronicle story.

Nobody seems to know, however, where this apparent 15 MPH ‘standard’ came from. On California roads, speed limits are set at the 85th percentile speed (approximately one standard deviation above the mean). But for shared use paths, everybody seems to use 15 MPH just because.

The 5 MPH limit is interesting. If I’m cruising at a relaxing 12 MPH on the bridge and get caught behind somebody jogging at 7 MPH, I’m stuck. I’m not allowed to pass. Wouldn’t a Critical Mass of joggers be a real hoot on the bridge sidewalk?

What’s your thought of a 15 MPH speed limit on the Golden Gate Bridge? Should the Bridge District spend staff time and consulting time on this issue?

You can see opinions of the previous 10 MPH proposal here. GGB sidewalk safety project info here.

20 Comments

  1. How would they enforce this?  Officer judgement?    And on a related note, has anyone actually heard of someone getting ticketed on a mixed use trail for cruising at 20 in a 15 MPH zone?

  2. Well, average cruising speed for a nondrafting road bicycle is ~16mph, which is a speed that causes significant wind resistance and requires effort.  Anything faster than 16 is deliberately fast and requires exceptional effort, due to greater wind resistance.  With that I presume a 15 mph speed limit in effect is saying don’t try to ride fast and slow up a little bit.  It seems reasonable enough to me.

  3. Well, average cruising speed for a nondrafting road bicycle is ~16mph, which is a speed that causes significant wind resistance and requires effort.  Anything faster than 16 is deliberately fast and requires exceptional effort, due to greater wind resistance.  With that I presume a 15 mph speed limit in effect is saying don’t try to ride fast and slow up a little bit.  It seems reasonable enough to me.

  4. The GGB staff report on this says tthey’ve approached CHP about this and CHP are willing to do enforcement. I don’t know if it would be walking or biking patrols though.

    Police on paths in the Denver area periodically write tickets to speeding path cyclists. I have’t heard of it in the Bay Area but that doesn’t mean it doesn’t happen.

  5. The GGB staff report on this says tthey’ve approached CHP about this and CHP are willing to do enforcement. I don’t know if it would be walking or biking patrols though.

    Police on paths in the Denver area periodically write tickets to speeding path cyclists. I have’t heard of it in the Bay Area but that doesn’t mean it doesn’t happen.

  6. Honestly, I can live with the 15 MPH limit. Remember, though, there’s a slope on the bridge, and wind gusts can be significant (okay okay, they’re never tailwinds…).   

     On that downslope side, Alta reports an average speed of 17 MPH. 1 standard deviation above that is 23 MPH.  So if you’re a commuter at 6 AM on that downslope with a 100 yard sightline and you like to hammer, do you really want to be limited to 15 MPH?

  7. I can live with 15mph. But what does “5mph when passing pedestrians” really mean? If pedestrians are spread out across the bridge span, no one wants to slow down to 5mph for every single one. If pedestrians keep to the right and there is no oncoming traffic, I think bicyclists can safely pass at higher speeds on the wide straight parts of the bridge. Maybe 5mph makes sense in narrower areas.

    The bridge people really need to focus on “keep right” instead of arbitrary speed limits.

  8. My question is if there is any authority under state law to 1) establish a speed limit on Class 1 bike paths, multi-use trails or sidewalks 2) enforce such a speed limit, and 3) by what means such a limit can be enforced. 

    As I understand it, the 85th percentile rule you refer to requires a study of road speeds every seven years in order to allow for radar enforcement on that street. I would be surprised if this sidewalk or any bike/multi-use trail has ever been surveyed in such a manner; wouldn’t that make use of radar invalid?

  9. I think the operative part of that question is “you like to hammer.”  What outliers want to do should be irrelevant.  Outlier drivers want to drive 120 mph on the highway.  It should be what is a reasonable limitation, and I think 15 mph is a reasonable limitation, even on the down slope, for everybody.  The riders can hammer before they get on, or after they clear, the bridge.

    Mind you, even if they enforce this with speed guns, they’re unlikely to write tickets unless you’re going over 5 mph over the speed limit.

  10. I don’t think my bike can go that slow without falling over. I can’t even manage the 8 mph on the boardwalk in Hermosa Beach; slowest I’ve been able to successfully manage in my lowest gear is 10.

  11. I apologize.  I was a humanities major.  Terms like ‘standard deviation of the mean’ are Mandarin to me (from what I gathered from just looking it up says that means 23mph was one extreme data point that fell within 2/3rds the data?); but my experience on bicycles tells me that a slope has to be mighty steep to go 23 mph without trying to go fast – and I’m not sure how, even if one did, why that would make it unreasonable to expect one to go a little bit slower.

  12. FWIW, our local MUPs have a 20mph limit. 5mph is a reasonable speed differential for passing but a speed walker will go faster than 5mph.If the little path is overcrowded, might the bridge allow more to cross (in total) by closing a main traffic lane? You can take a lot of peds and cycles for a traffic lane and I recall that the all-time record for the Brooklyn Bridge came before the advent of four-wheeled motor traffic.

  13. Why are you on the sidewalk with a roadbike?  Is there some reason you cannot ride of the road?  I am from Florida so I don’t know the laws in California but here bicycles are vehicles so with the exception of the interstate which has a minimum speed limit of 45 I don’t know why you wouldn’t just drive your vehicle (aka bicycle) on the road?

  14. Because the “road” of the golden gate bridge is a freeway (I-580 I think).  There are NO traffic signals, it’s perfectly straight and speeds of 50 to 70 MPH are the norm just like your interstate.  Believe me, I’d LOVE nothing more than to bomb down the Golden Gate Bridge but not with cars that are easily 30 MPH faster than me (not much of a reaction time for most drivers).

  15. Just a thought…but if a cyclist is not permitted to exceed 5mph while passing and he collides with a pedestrian, it will be far easier to find the cyclist at fault for the collision because he was obviously riding well above the speed limit. Otherwise, the collision wouldn’t have happened.

    Am I being paranoid or realistic?

  16. Interested to hear about this (from a UK perspective). As far as I’m aware, we don’t seem to have separate speed limits for bicycles, unless I’ve missed them!

  17. @openid-37602:disqus  – I have a long history of advocating road use for bicycles. In California, bikes are prohibited from toll roads and bridges.  Many San Francisco and Marin cyclists would love the legal right to cycle across on the local toll bridge roadways. There are occasional protest rides in which cyclists try to cross the Bay on the roadway of one of the toll bridges, but they get caught pretty quickly.

  18. @c5f51adb284631469a52f7d6f81e29eb:disqus GGB is designated US101 and State Highway 1, but the law that prohibits bikes on the roadway is CVC 23330 (“Toll Crossing” law), not CVC 21960 (“Bicycling on Freeways”).  The distinction can be important: The default for freeways is bicycles are permitted, and Caltrans must install signs where bikes are prohibited.  On toll bridges, the default is bicycles prohibited, with signs installed to show if bikes are allowed. 

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