Thursday, September 23, 2010

MTA Installs Permanent Radar Speed Displays on Masonic

One element to the traffic calming needed on Masonic

Installation of northbound display today

Southbound display board to be mounted on light pole Monday

The Municipal Transportation Agency (MTA) started installing permanent speed radar displays on Masonic Avenue today to inform motorists when they are driving at unsafe speeds. The southbound display is mounted between McAllister Street and Golden Gate Avenue while the northbound board will be placed Monday closer to the McAllister intersection. According to Javad Mirabdal, MTA manager for the Masonic traffic calming project, the locations were selected to notify motorists just as they might be inclined to start speeding with the change in grade. Other considerations were availability of a power source and tree clearance.

Mirabdal has a good read on driver behavior on Masonic. In a 20 minute period this afternoon when traffic was relatively light, the most common speeds reflected on the board were in the mid- 30s to mid-40s. Speeds in the low-20s to mid-20s generally occurred when the signal light ahead had changed to yellow or red -- or perhaps when drivers noticed the new display. The posted speed along the Masonic corridor is 25 mph.

The speed radar displays were installed in response to calls for immediate safety measures on Masonic, especially following frequent collisions, injuries, and a fatality last month. MTA Executive Director Nathaniel Ford, Supervisor Ross Mirkarimi, FixMasonic, the San Francisco Bicycle Coalition, and the North of the Panhandle Neighborhood Association have urged city staff to study and implement safety changes to Masonic while a full review of the street traffic design is underway. Another measure yet to be implemented is a temporary bicycle lane between Ewing Terrace at the north and Fulton Street to the south, a stretch of several blocks where bicyclists are at most risk due to increased motorist speed and reduced visibility due to the grade of the street.

The speed radar display boards installed on Masonic do not include photographic capabilities similar to red light cameras, and they do not rely on speed enforcement. Lt. Mark Solomon, Acting Captain at SFPD Park Station, explained that the display boards are "informational only." Traffic officers cannot use them for issuing warnings or tickets. "We use radar guns, and those have to be certified. Officers who use them also must be certified as trained in their proper operation." Solomon said the display boards are effective on their own, however. "You can watch drivers hit the brakes when they go by and notice they're speeding."

One study has found speeds reduced 5 to 6 mph where baseline speeds averaged 35 in 25 mph zones like those on Masonic. More significant reductions were found on streets where speeds exceeded the speed limit by 10 mph or more. Masonic residents, bicyclists, and pedestrians often complain of speeds they judge to be 35, 4o, 45 mph or more.

MTA has regularly added traffic calming features to Masonic. The most recent prohibited left turns onto Golden Gate Avenue during the morning and evening commutes. MTA engineers are also studying whether signal light timing can be adjusted to discourage speeding between signal changes on the street. Progress on that effort has yet to be disclosed.

Note: The display board mounted today may require fine-tuning, according to the electricians who installed it. The grade of the street, the slant of the sidewalk, and the angle of the board on the pole -- all make accurate placement more challenging. The work should be completed on both displays by early next week.

For more stories in the A Better Masonic series, check here.


  1. This is really NOT what the calming of Masonic is ALL about! I applaud SFMTA for installing this informational signage, BUT the REAL solution is to retime the traffic signals to reflect the 25 MPH speed limit.

  2. Doug: Traffic calming for a complete street can seldom be achieved by any one measure standing alone. Certainly not by a pair of radar speed displays, or, in my opinion, re-timed traffic signals, or the addition of bulb-outs,a bike lane, periodic enforcement, or a median. Masonic will become a safer street that works for all users and for residents when the complete package of tools are used together.

  3. Doug: But to be clear about what I mean, I have changed the caption for the first photo. Thanks for your comment: it prompted me to be more precise. (For the curious who are reading this post for the first time: the original caption was "This is what traffic calming is all about." Not by itself, it isn't!)

  4. Thanks, Mike On Bike. I guess I can be a bit impatient for all of the tools to come together. All the more reason for interested parties to attend the SFMTA Masonic public meeting on Thursday, Sept. 30, 6:30 PM at the San Francisco Day School.

  5. gonna head out on Monday to see if I can get above 40 mph on my fixie!

  6. I just checked the display boards this morning and the southbound sign looks to be right on the money. The northbound display board has some time delay issues and sometimes goes completely blank even when vehicles are in it's range. I hope that SFMTA can tweak it to work a bit better.

  7. Doug: Thanks for checking, MTA is aware of the problem. The northbound display needs to be adjusted, probably its radar. It currently is not registering speeds on the inside NB traffic. Also the SB display needs a 25mph sign added to the pole for reference.