That means six of the seven state-owned bridges in the Bay Area, plus the Golden Gate Bridge, all have some sort of bicycle or pedestrian access. The only links without such a path: the western span of the Bay Bridge and the San Mateo-Hayward Bridge.

While one might tend to see cycling and walking paths across the bridges as purely recreational amenities, the lanes are getting new scrutiny as serious commute and travel options. That's in part because of a dramatic increase in urban cycling in San Francisco, Oakland and other core Bay Area cities in the last decade. Another major factor: the growing popularity of electric-assist bikes that make longer-distance rides, like commuting across your local bridge, less of a physical challenge than it has been in years past.





The new Richmond-San Rafael bike/pedestrian route — or "people path," as cycling and walking advocates call it — is getting more attention than any of the other non-motorized crossings. That's because the path is not necessarily a permanent bridge feature but instead a four-year pilot project that will study how heavily it's used and what impact it has on other modes of traffic across the bridge.

The path, separated from vehicle traffic by a 42-inch-high, movable concrete barrier, occupies a westbound upper-deck lane that was taken out of service during the drought of 1976-77 to install a water pipeline from the East Bay to then-parched Marin County. The pipeline was used for just a few months, but it was left in place for several years. When it was removed in 1982, the old right-hand traffic lane was left open for maintenance crews and vehicles that needed to move out of traffic.

A third traffic lane on the eastbound lower deck of the bridge was also removed from service, in 1980, to create a maintenance/breakdown lane. That third lane was put back into service for motor vehicles in the spring of 2018, a $36 million project designed to ease a choke point for evening commute traffic from U.S. 101 in San Rafael to Interstate 580 and the bridge.

Some officials in Marin and Contra Costa counties have lobbied for something similar on the Richmond-San Rafael span's upper deck. Their idea, meant to ease long morning rush-hour delays at the bridge's toll plaza, is to restrict bike and pedestrian use of the lane to non-commute hours.

That proposal has gone nowhere, for now. But local and regional officials, along with Caltrans and a team of transportation researchers from UC Berkeley, are watching how the new people path performs and how it affects overall bridge traffic.