Bay Area/ San Francisco/ Transportation & Infrastructure
Published on July 03, 2019
10 of SoMa's most treacherous intersections poised for safety upgradesImages: San Francisco County Transportation Authority

County transportation planners will vote next week on a $10.5 million proposal to improve pedestrian and vehicle safety at 10 of SoMa’s most treacherous intersections.

There are 22 spots in SoMa where freeway entry or exit ramps intersect city streets, each of which have been targeted for safety improvements through various city, county, and state projects. If the San Francisco County Transportation Authority (SFCTA) votes in favor of the improvements at its July 9 meeting, 10 of the most dangerous ones could get upgrades. 

Making these intersections safer will have a big impact: according to SFCTA, SoMa could add as many as 20,000 new residents and 50,000 new jobs by 2040, representing 20% of all growth projected for San Francisco during that period. 

Map of near-term planned residential and business developments in SoMa

Each of the 10 intersections are part of the Vision Zero high-injury network, representing the crossings in San Francisco with the highest concentrations of severe and fatal collisions. The Vision Zero program calls for the elimination of all traffic-related deaths in San Francisco by 2024. 

Here's a roundup of the intersections, and the improvements proposed for each: 

Map of the 10 intersections targeted.

    Mission, Otis, Duboce, and 13th streets (U.S. 101 northbound off-ramp) 

      This intersection was found to have the highest number of collisions from 2012 to 2016 — 35 in total — as well as the highest number of collisions that caused severe injuries.

      The majority of the incidents occurred on the east side of the intersection and at night, according to SFCTA, because visibility in the wide pedestrian crossings across the four-way intersection is limited. Pedestrians crossing at the southeast corner and cyclists rolling through red lights were the most common victims; vehicles making illegal left turns also caused some serious injuries.

      The Market Street Hub Project is already adding protected bicycle lanes on 13th and Duboce, and will realign the US-101 on-ramp to improve visibility, particularly for cyclists.  

      Recommended improvements:

      • Sidewalk bulb-outs and curb ramps
      • Median refuge islands for pedestrians crossing Duboce and 13th streets
      • Brighter under-bridge lighting and crosswalk flashing beacons
      • Improved pedestrian and traffic signals
      • Bus-only lanes on Mission Street

      South Van Ness Avenue and 13th Street (U.S. 101 southbound on-ramp) 

      The second most dangerous intersection in SoMa, this area saw 32 collisions in the 2012-2016 period, most of which occurred in the central area of the intersection. The incidents were caused by red light violations, unsafe lane changes, and unsafe turning maneuvers, mostly caused by vehicles heading southbound on South Van Ness Avenue or eastbound on 13th Street.

      The wide intersections make signals difficult to see clearly, and most collisions occurred at night. The Market Street Hub Project is already improving bicycle safety in the area by adding a protected bike lane on 13th Street. 

      Recommended improvements:

      • Sidewalk bulb-outs and curb ramps 
      • Median refuge islands across 13th Street 
      • Pedestrian crossing and traffic signal upgrades, including a new protected left turn from South Van Ness Avenue to 13th Street 
      • Adding a sidewalk on west side of S. Van Ness Avenue

        Eighth Street midblock between Bryant and Harrison streets (I-80 westbound off-ramp) 

          There were no collisions recorded at this location from 2012 – 2016, but the angle of approach and existing shrubbery make it hard to see pedestrians at the southeast corner of the intersection. 

          SFMTA’s Eighth Street Safety Project is already adding a new transit boarding island. 

          Recommended improvements:

          • Sidewalk bulb-outs and curb ramps 
          • Crosswalk improvements including flashing beacons yield line upgrades 
            Excessive speed at freeway on- and off-ramps causes many of the traffic collisions in SoMa.

            Eighth and Bryant streets (I-80 westbound off-ramp) 

              Many of the 19 collisions that occurred at this intersection were caused by drivers heading southbound going too fast, and three were caused by drivers trying to avoid the freeway on-ramp at the last minute. During heavy traffic, drivers often try to merge onto the freeway from the non-“freeway-only” lanes, or use the tow-away lane to get ahead of other waiting cars.

              There are also limited sidewalks, and no areas for bikes to queue while waiting at the intersection. The second phase of SFMTA’s Eighth Street Safety Project will add a transit boarding island and new protected bike lane on Eighth Street.

              Recommended improvements:

              • New crosswalk across Bryant Street with protected signal phase 
              • New sidewalk along north side of Bryant Street, and sidewalks bulb-outs and curb ramps
              • New crosswalk across on-ramp with new traffic signal
              • Median refuge island modification and crosswalk striping upgrades 
              • Overhead lane assignment signs and traffic signal upgrades to improve visibility

              Seventh and Harrison streets (I-80 westbound on-ramp)

              Four out of the 13 collisions that occurred at this intersection resulted in pedestrian injuries, mostly due to drivers moving at unsafe speeds or running red lights.

              The pedestrian crossing across west Harrison Street is currently closed, and the southwest corner of the intersection has a wide radius. A new pedestrian signal is being installed at the I-80 ramp crosswalk through Caltrans’ I-80 On-Ramp Project Improvements, which is also upgrading the traffic signals for the ramp.

              A protected bike lane and new transit boarding island is already planned in SFMTA’s Seventh Street Bikeway Project. 

              Recommended improvements:

              • New signalized pedestrian crosswalk across Harrison Street 
              • Median refuge islands across Seventh Street 
              • Sidewalk bulb-outs and curb ramps 
              • Bus bulb at south side of Harrison Street, east of the intersection

                Seventh Street midblock between Bryant and Harrison streets (I-80 eastbound off-ramp) 

                  This intersection’s five collisions were all clustered in one area, where vehicles exit the freeway and are supposed to yield to cross traffic. The off-ramp design, with two approach lanes, limits pedestrian visibility.

                  A protected bike lane and new transit boarding island is already planned in SFMTA’s Seventh Street Bikeway Project. The improvements recommended at this intersection will require Caltrans approval and Muni re-routes.

                  Recommended improvements:

                  • Reduce the off-ramp to one lane from two lanes 
                  • New sidewalk bulb-outs and curb ramps 
                  • Crosswalk improvements, including flashing beacons, signage, striping and yield line upgrades 
                  Breakdown of collision types by intersection.

                  Seventh and Bryant streets (I-80 eastbound off-ramp) 

                  This intersection had eight collisions from 2012 to 2016, including two vehicle-on-pedestrian collisions in the same area at the east corner. In both cases, the vehicle was making a right turn from Seventh Street onto Bryant Street.

                  The wide intersection increases pedestrian and cyclist exposure to oncoming traffic, especially at the eastern side that crosses two different east-bound approaches, from Bryant and the I-80 off-ramp.

                  A protected bike lane is planned on Seventh Street, as part of SFMTA’s Seventh Street Bike Lane Project. 

                  Recommended improvements: 

                  • Lane reduction from three to two on the I-80 offramp approach (requires Caltrans approval)
                  • Sidewalk bulb-outs, curb ramps, and a new bus bulb 
                  • Signal and crosswalk striping upgrades and additional pedestrian level lighting 

                  Sixth and Brannan streets (I-280 northbound off-ramp, I-280 southbound on-ramp) 

                  Of 11 total collisions at this intersection, three were vehicle-on-pedestrian collisions in the east corner. In all three instances, a driver exiting the I-280 off-ramp and making a right turn onto Brannan was found at fault.

                  There are no existing bicycle facilities along any approach, and the pedestrian crossing at the south (I-280) approach is closed.

                  SFMTA’s Sixth and Brannan Road Diet Project is adding bike lanes and reducing vehicle travel lanes, and the sidewalk along Sixth Street may be widened. 

                  Recommended improvements: 

                  • Sidewalk bulb-outs, curb ramps and median refuge islands 
                  • New crosswalk and median refuge island across the I-280 approach 
                  • Protected pedestrian signal phase for Brannan crosswalk on east side of intersection 
                  • Additional high-visibility crosswalks and traffic signal upgrades

                  Fremont Street midblock between Howard and Folsom streets (I-80 westbound off-ramp)

                  This new intersection, which was signalized in 2015, did not have collision data available for the study period. But SFCTA found that the lack of marked pedestrian crossways and bike facilities reduce the visibility of non-vehicular traffic.

                  Recommended improvements:

                  • Add new crosswalk and pedestrian signals across Fremont Street 
                  • Upgrade existing crosswalk striping and curb ramps
                  • Add a raised traffic island

                  Harrison and Essex streets (I-80 eastbound on-ramp)

                  The 10 collisions at Harrison and Essex streets were mostly clustered in the western portion of the intersection, most of them due to drivers speeding or running red lights. One of the collisions was between a pedestrian and a bicyclist.

                  Drivers often enter the bus-only lanes eastbound on Harrison to get around traffic queued to enter I-80. The pedestrian crossings at the south and west approaches are closed, and the wide intersection has bridge piers that restrict visibility. 

                  Recommended improvements:

                  • New protected crosswalks across Harrison Street and I-80 on-ramp 
                  • New sidewalk on south side of Harrison, west of the intersection 
                  • Additional traffic signal upgrades and sidewalk bulb-outs

                  If the SFCTA votes in favor of the plan next week, some of the less intensive improvements, such as improved crosswalk striping and signage, could occur in the next two years. 

                  Others could take a while to receive funding. While the money for the study came from Proposition K Local Transportation Sales Tax funds and a grant from Caltrans, the SFCTA and its project partners are still seeking money for the larger-scale upgrades.

                  Potential funding sources identified so far include the Prop K Neighborhood Transportation Improvement Program; District 6 funds for near-term improvements at the first several intersections; and fees from nearby developments. 

                  "The process of seeking funding will be ongoing with the goal of constructing the longer-term improvements in five years, if possible," according to SFCTA spokesperson Eric Young. "SFMTA will be developing their next five-year Capital Improvement Plan update next year... so that's an opportunity to look at City funding sources... [and] grant opportunities and developer funding also arise on a rolling basis," he added.