Fix the Hairball

The only pedestrian connection to Southeast San Francisco.

The hairball is the name of a dangerous intersection underneath the US-101 and Cesar Chavez streets, relied upon by walkers, bikers, and drivers alike.

This page is a grassroots petition to show community support for improving this intersection.

This is a recent video of the intersection at night, traveling Southbound, by bike.

Not sure why my GoPro says this was 2022... this was taken March 2025.

The Hairball's Location

See the US-101 and Cesar Chavez intersection below.

This is a vital crossing for the Mission, Bernal, Portola, Bayview, and Potrero neighborhoods.

No Alternative Intersections

This is the area's ONLY crossing that does not involve climbing the city's steepest hills (Bernal, Potrero).

Going around it requires doubling or tripling one's distance traveled.

List of issues

No lighting: Area is pitch-black after sunset (430 pm in the winter)!
Several curbs and sidewalks are too narrow, or too close to vehicles.
Intersections with vehicles have major blind spots. Vehicles do not yield.
There are persistent encampments with items across the sidewalk.
Some pedestrian paths lead directly into vehicle traffic with no protection.

Ways to improve the intersection:

Add lighting (permanent or motion-sense) for usage at dark.

[SFMTA Walkthrough] See lighting section here

Widen several curbs for accessbility and safety.

[SFMTA Walkthrough] Short-term and long-term plan addresses most curbs.

Add mirrors to eliminate vehicle-to-pedestrian blind spots.

[SFMTA Walkthrough] Mirrors are rarely used in traffic practice for vehicle-to-pedestrian/bike visibility. They would not work well in the constrained off-ramp areas of the hairball.

Add fence between Potrero Northbound and Sidewalk.

[SFMTA Walkthrough] It is unclear that the fence will not add new hazards for pedestrians/bikers here without expanding the bridge, which is not in scope for the short or long-term changes. A bridge upgrade requires a major transit project upwards of $10M, potentially $100M

Consider adding traffic slowing measures.

[SFMTA Walkthrough] Several areas are highlighted in for traffic-slowing measures in the August 2025 Short-term and long-term planning. See here

Add signage for both pedestrians (e.g. a map of hairball) and cars (yield signs, flashing lights).

[SFMTA Walkthrough] Wayfinding signs have been added to the short-term planning (thanks to this petition). Flashing Beacons Flashing Beacons are included in the long-term plan as well.

Protected bike lane, could use crash barriers such as these identified by this 2017 article.
- [SFMTA Walkthrough] Short-term plan adds concrete barriers to protect the bike lane.

Show your support!

If we can get 100s of signatures this fall, maybe we can convince the city to take action before Winter 2025.

Community Support

Supported by these local organizations! Contact borde.akash@gmail.com to be added to this list.

Safe Streets Bernal

Eastside SF Bike and Scooter Alliance

Portola Neighborhood Association

SF2G

Streets for All SF

SFMTA Walkthrough

Notes and observations from the SFMTA walkthroughs and guidance on recommended lighting/visibility improvements. See the official SFMTA resources for full details: sfmta.com.

Didn't they already "fix this intersection"?

There have been serious improvements over time, including those listed below. However, as the pictures, videos, and comments show, there is still a way to go. Regardless, it is important to acknowledge the progress made.

East-west bike-only paths along Cesar Chavez
Bike Lane Designation
Evening of Sidewalk Grade
Widening of Sidewalks
Installation and positioning of crosswalks

The hairball is the name of a dangerous intersection underneath the US-101 and Cesar Chavez streets, relied upon by walkers, bikers, and drivers alike. This page is a grassroots petition to show community support for improving this intersection.

See the US-101 and Cesar Chavez intersection below. This is a vital crossing for the Mission, Bernal, Portola, Bayview, and Potrero neighborhoods.

This is the area's ONLY crossing that does not involve climbing the city's steepest hills (Bernal, Potrero). Going around it requires doubling or tripling one's distance traveled.