San Francisco is a crowded city with great transit ridership. To prioritize buses and streetcars over cars, they’ve set aside dedicated lanes for years. But now to send a signal to drivers to keep out, they’ve painted some lanes red. The data shows it’s working wonders.

Church Street, south of Market in San Francsico. Photo by the author.

This is Church Street, a north-south street that carries trolleybus line 22 and the Muni Metro light rail J line. The central transit-only lanes have been there for several years. But they were only painted red in the early months of 2013.

Less than two months later, San Francisco’s transit operator, SFMTA, reported that travel times on the 22 and the J were down 5% and on-time performance for those lines had increased 20%.

That’s a big improvement for the some 15,000 riders who use these lanes each day. Especially considering the painted lanes only stretch for three and a half blocks.

Painting the lanes red sent a signal to drivers that “bus lane” stenciled on the pavement didn’t seem to send.

Building on the success of the Church Street red lanes, SFMTA has been rolling out more red paint across the city, and has plans for still more in coming years.

New York has also been painting the town red with lanes for its Select Bus Service. Other American cities, including Seattle and Chicago have plans to introduce red lanes in the near future.

While the Washington region doesn’t have very many bus lanes today, there’s been talk of installing more. But they’ll only work if drivers stay out.

Red paint, much like the green paint DDOT is now using to mark bike lanes at conflict points, could go a long way to keeping DC’s bus lanes free of scofflaw motorists.

Matt Johnson has lived in the Washington area since 2007. He has a Master’s in Planning from the University of Maryland and a BS in Public Policy from Georgia Tech. He lives in Dupont Circle. He’s a member of the American Institute of Certified Planners, and is an employee of the Montgomery County Department of Transportation. His views are his own and do not represent those of his employer.