Green City: Reaching critical mass

Pub date September 25, 2007
SectionGreen CitySectionNews & Opinion


GREEN CITY Fifteen years ago this month, San Franciscans mobilized for the first Critical Mass, an unpermitted monthly bicycle parade and social protest that has subsequently been exported to cities around the world.

The movement formed in the streets as the Commuter Clot, just a handful of bicyclists seizing their stretch of pavement together. Among them rode former bike messenger Jim Swanson, whom many credit with coining the name Critical Mass, a reference to the traffic-controlling power achieved when enough bicycles join a ride.

Two months into the project, Swanson watched Ted White’s short film The Return of the Scorcher. The surreal footage of bicyclists in China fording intersections inspired Swanson: "When there was enough of them, they crossed and took over the road."

Thus, in September 1992, the autonomous and leaderless collective known as Critical Mass was born, picking up momentum — while enduring an often rocky relationship with the city and its motorists — ever since.

On Sept. 28, around 6 p.m., thousands of bicyclists are expected to convene around Justin Hermann Plaza for the 15th anniversary ride, just as they do on the last Friday of every month. Each rider brings a unique cause and perspective to the ride. Swanson wheels out his 1965 blue Schwinn Tandem each month and makes it a regular date with his sweetheart and friends.

Longtime rider Joel Pomerantz focuses on the political undertones of the event. "For me, the ride is about community. It’s an opportunity for people to take over public space that is usually destructive to the community," he told the Guardian.

During Critical Mass, riders change the use of street space and establish bicycles as the dominant form of transportation, taking control of every intersection they encounter, at least for the 10 or 15 minutes it takes the mass to pass.

Bicyclists in San Francisco have also attained critical mass in other ways, with more and more residents realizing the environmental, health, safety, and monetary benefits of trading the gas pedal for a pair of pedals. The 35-year-old San Francisco Bicycle Coalition now boasts a peak membership of 7,500, and the city has the highest per capita membership in the Thunderhead Alliance, a national conglomeration of cycling and walking advocates.

According to the Urban Transportation Caucus’s 2007 report card, automobiles and trucks account for 50 percent of San Francisco’s carbon emissions, a major cause of climate change and respiratory ailments. "Simply reducing the number of driving vehicles will be the biggest thing in reducing carbon emissions and improving people’s health. Bicycling comes up as the most cost-effective way to reduce private vehicle trips," SFBC director Leah Shahum said.

Some groups want to take big steps toward furthering that trend. For example, San Francisco Tomorrow is pushing a plan to ban private automobiles on Market Street. But for now the city is prevented by a court injunction from undertaking bike-friendly projects after a judge found procedural flaws in how the current Bicycle Plan was approved (see "Stationary Biking," 5/16/07).

Carla Laser, founder of the San Francisco Bicycle Ballet, said getting the plan back on track is also essential to minimizing bike-car conflicts: "The striping of bike lanes is an example of how the Bike Plan educates the public on how to share the streets. Drivers can clearly see that the city actually supports bikes on streets and is willing to give them a nod of space with the stripes. Every street is a bike street."

That’s especially true for Critical Mass, a situation that can cause tensions between motorists and cyclists and fuel a backlash toward bike riders seen as overreaching into the realm of automobiles. Yet Critical Mass remains more popular than ever, and it only seemed to grow larger a few months ago, when the San Francisco Chronicle publicized some motorist-cyclist clashes (see "Did Critical Mass Really Go Crazy?," SFBG Politics blog,, 4/4/07).

Yet as the event becomes a popular rolling party, some longtime massers have started openly wondering what’s next for those looking to send a serious message about minimizing dependence on cars.

As transportation activist and former SFBC executive director Dave Snyder told us, "I’m looking forward to the next public phenomenon in San Francisco that inspires a humane use of public space, as Critical Mass was to so many people."

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