State Sen. Scott Wiener’s bill to overrule low-density zoning near mass transit lines isn’t the political pariah it used to be. Thanks to a series of conciliatory amendments and perhaps the accumulating devastation of the housing shortage, Senate Bill 50 has substantial new support from previously unlikely sources, including the local governments that have put up some of the most determined resistance.

The BART Board of Directors voted last week to endorse SB50, the successor to the San Francisco legislator’s ambitious and contentious SB827, which his fellow Democrats killed in committee last year. San Francisco’s Planning Department signaled a more sympathetic view of the revised legislation in a report released the same day, finding it “likely to result in significantly greater housing production” and “more affordable housing.” Even in San Mateo County, that hotbed of anti-housing sentiment, Supervisor David Canepa urged his colleagues to support the bill, albeit unsuccessfully.

The measure’s growing constituency also includes environmental groups, trade unions, and the mayors of San Francisco, Oakland, San Jose and Sacramento. A poll commissioned by the San Francisco Chamber of Commerce last month found that about three-quarters of the city’s residents support its goals.

A series of amendments since the legislation’s first iteration has refined the areas defined as close to mass transit and reduced automatically allowed building heights from eight to four or five stories. The changes also set minimum affordable-housing requirements for new developments and added protections for existing rental housing and vulnerable neighborhoods. And in an effort to encompass exclusive suburbs without extensive train or bus service, Wiener added a provision that applies to areas with jobs-housing imbalances regardless of transit proximity.

In a state that has the least housing per person on the U.S. mainland and almost half the country’s unsheltered residents, SB50 is an idea whose time should have come long ago. But even last week, hearings in San Francisco and Palo Alto drew crowds eager to defend the indefensible status quo and to prevent the Legislature from, as a San Carlos official put it to the San Mateo Daily Journal, “invading the sanctity of our single-family neighborhoods.” The dedication and persistence of California’s housing deniers should not be underestimated.

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