Monday, March 16, 2009

More Geary BRT thoughts

Anonymous #1 wrote:
I think DPT is enabling signal priority on Geary already. That has been called a given with all of the Geary BRT meetings. It's not clear how useful it will be because of some specific issues:

1. The timing challenge is with pedestrian crossing times. Generally, San Francisco allows enough time for a pedestrian across the street (avoiding those pesky push buttons). Geary is a wide street so pedestrians need a lot of time to cross. Thus, it is almost impossible to turn a light green prematurely---unless you want to run over a pedestrian!

2. One other issue is that Geary buses are so frequent that the signals could not recover from constant timing manipulation.

3. One feature of the BRT design is called an "extended cycle," which keeps the light green enough to let the bus go through it to the next stop. When the Geary BRT evaluation was done a few years ago, what came to light was that the greatest delay is associated with loading so many people onto the buses. Setting up something like a median station would enable a "paid fare" area and multi-door loading making the dwell time much shorter. Oh---low floor buses really help too!

The Geary costs could skyrocket depending on what happens with Masonic and Fillmore. The new vehicles, new street median, stations, striping and signal work would not come close to $200 million.

Rob writes:
Thanks for the thoughtful comment, Anon. I got the $200 million figure from a story in the Examiner a few years ago that put the cost in the range of $172 million to $212 million.

I'm becoming less skeptical of the necessity of some kind of BRT on Geary, especially after my eye-opening journey on the #38 from the beginning of the line and experiencing the blizzard of stoplights from 33rd Avenue to Masonic. I'd like to hear more about the Masonic and Fillmore problems, though I assume that will be covered in the EIR on the proposal. Do you know when the EIR is going to be released?

Anonymous #2 wrote:

Years ago the TA installed a signal priority system on a segment of Geary which failed for a number of reasons. As the first commenter pointed out, the constant manipulation of timing just made things worse. It was also based on infra-red which stopped working when the signal mounted receivers got covered in dirt and grime, though that was a limitation of that specific technology. Rear-door boarding and low-floor buses do not require any changes to the street and the TA could fund those buses out of Prop K today since the money was already supposed to be set aside. That might be a good move, since the SF MTA is planning to cut back on bus maintenance to cover it's deficit, and that's likely going to mean even less reliable service due to break downs.

BRT would help with crossings by creating additional medians in the middle of the street to provide pedestrian refuges. Even though it doesn't actually narrow the street, it changes the perception. This can be taken another step further by also extending the corner sidewalks out because the space currently used at corners for bus stops will be converted into additional parking spaces.

BRT will improve service by eliminating the delays caused by pulling in and out of the corner stops, this last benefits traffic as well as taking buses out of the car lanes, but some of that delay can be mitigated by moving bus stops to the far corner of the intersection, after the light, where a bus will not have to wait through an entire signal if it finishes boarding right as the light turns red. Likewise it will be able to pull out of the stop while traffic is being held at the light, but there are downsides to this as a bus may be ready to pull back into the street right as the light turns green and has to wait through the signal until traffic stops when it goes red again and then for the cars that had been waiting to turn go ahead. There are probably only a limited number of stops where far-side stops would be useful.

To those who've suggested BRT would divert traffic onto parallel streets, there's a few other factors to keep in mind: Though Geary would be losing two lanes to traffic, it would also no longer have buses pulling in and out of traffic every block slowing things down. Calfornia, Clement and Balboa would all still have that issue and not even all of them are through streets. They would not become instant expressways any more than 18th or 20th Avenues are faster alternatives to 19th Avenue. The TA had estimates of what that spillover would be---and I do not remember what it was---but it was incredibly low (something like one extra car/min) and could be absorbed, but I suspect most drivers will just stick with Geary because it's the major expressway and not all the other side streets go all the way to downtown and would require crossing over to Geary anyway, so why would I bother if I'd lose the couple minutes I saved having to do that.

Another issue that would effect Geary if BRT was put in would be the additional traffic pulling in and out of the 16% of additional parking created by moving the corner bus stops to the center median. Adding more parking could attract people away from Muni and add more traffic to Geary than could be convinced to take Muni instead were the Geary buses more convenient.

Anonymous #3 wrote:
All this stuff about putting the road on a diet and creating some kind of pedestrian utopia assumes anyone would want to go shopping along Geary. The city already has a lot of well established shopping districts where people are already coming by transit and could use wider sidewalks. San Francisco should focus on making already walkable neighborhoods like the Upper Haight, Castro, Noe Valley, Valencia and the like more walkable and stop fighting an uphill battle with suburbanites with a 1950's mind set about traffic and transit.

Rob writes:
You mean we should just abandon the many people who live out on the avenues and simply write them off as "suburbanites"? Not a particularly helpful approach, since it's one of the most densely populated areas of the city. People are already there and shop where they live, not to mention the fact that many of them now ride the #38 line downtown from deep in the avenues.

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