San Francisco is about to roll out the red carpet for buses. Currently, Muni buses travel in several bus-only routes, painted bright red. But according to the San Francisco Examiner, the agency is now contemplating a massive expansion for the pilot, involving about 50 new streets. That’s good news for bus riders and transit planners, but not such great news for everyone, according to an alliance of homeowners and merchants who “decry the lanes for making traveling by car more difficult, potentially driving away customers from mom and pop shops,” according to the paper.

New federal approval is behind the city’s expansion. Red transit lanes are still “an experimental device,” a spokesperson for the Federal Highway Administration told the Examiner. The administration is open to crafting laws around them nationally, and will study San Francisco’s success (or failure) to determine whether and how to legalize them.

From the paper:

The SFMTA was granted the ability to expand its use of red lanes as an “experiment” across San Francisco on June 2 by the administration. Some of those lanes are existing transit-only lanes, but are not red, and many of them require further planning and approvals by the SFMTA Board of Directors, according to agency records.

When installed, the SFMTA will report back to the highway administration on the number of vehicles driving in transit-only lanes, parking violations in the lanes, the behavior of private vehicles turning and blocking buses, collisions and transit travel time to measure their success.

As Next City has previously covered, designing successful bus-only lanes can be challenging. In Washington D.C., bus-only lanes were first constructed around 1962, but the city’s prioritization of on-street public transit weakened over the years as the political clout of motorists strengthened and subway lines chipped away at ridership numbers (and fares). On the Shirley Busway, for example, which had been a kind of bus-only freeway, the city began admitting HOV vehicles.

After that, “many of the routes suffered from delays, snags and compromises common to bus-priority lanes,” I wrote in 2014. “They crawled along the curb, stuck behind HOV vehicles turning right onto streets and into parking garages.”

In 2014, WMATA, the region’s transit agency, opened a BRT line that borrowed many ideas from the ’60s. So far it’s expanded in both length and number of stations. San Francisco is also taking the first steps toward BRT, as Josh Cohen wrote for Next City in January.

A detailed map of San Francisco’s proposed red lanes can be viewed here.

Rachel Dovey is an award-winning freelance writer and former USC Annenberg fellow living at the northern tip of California’s Bay Area. She writes about infrastructure, water and climate change and has been published by Bust, Wired, Paste, SF Weekly, the East Bay Express and the North Bay Bohemian

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