San Mateo Bridge Transit

A fact of life on the Peninsula is that during rush hours, the 101 freeway is jammed in both direction leading to SR-92 and SR-92 is also jammed leading to the San Mateo Bridge. Unfortunately, unlike nearly all other Bay Area bridges, this bridge has no transit option currently for the general public nor a route for cyclists. Commuters either have to drive themselves, make informal arrangements for carpool, lucky enough to have employer sponsored shuttles, or use other bridge corridors on transit or bike/micromobility. Why hasn’t transit worked for the San Mateo Bridge?

Remaining portion of original bridge that turned into a pier (right). High rise portion of the current bridge (left).

Even though the San Mateo-Hayward Bridge first opened to traffic in 1929, and being the second road bridge to be opened crossing San Francisco Bay (after Dumbarton Bridge), I was not able to find history of scheduled bus service on the bridge before SamTrans introduced the 90E route between San Mateo and Hayward BART in 1977. In the early decades, the Peninsula and East Bay regions outside Oakland and Berkeley were mostly rural. Primary transbay transit service was ferries from Oakland and eventually interurban rail and buses over the Bay Bridge.

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The 90E provided primarily weekday peak commute service over the bridge. Service was increased temporarily after the 1989 earthquake when the Bay Bridge was shutdown due to damage. Ridership on the line wasn’t high and discontinuation of the route has been proposed in the 90s. As funding got tighter and SamTrans shifted priorities to fund BART extension to SFO, SamTrans finally discontinued the 90E service in the 1999 service change.

In the meantime, a free shuttle route was funded to provide service from Hayward BART to Foster City businesses. At that time, there was expectation for AC Transit to provide replacement service, as it is based in the East Bay where most bridge commuters originate.

In March 2003, soon after the completion of widening of the causeway section of San Mateo Bridge, and with new MCI coaches brought with the 2000 state surplus (TCRP) funds, AC Transit introduced the M Line in March 2003 connecting Castro Valley to San Mateo via Hayward. the service was initially offered during the midday period as well as on weekends paid by regional grants.

Line M promotional banner.

Three years later in 2006, AC Transit added another route (MA) that began at Union City BART to the Oracle headquarters in Redwood Shores via the San Mateo Bridge. That route operated only during weekday peak hours.

Despite the seed funding, the ridership was below expectation, particularly for MA. In December 2007, the MA route was discontinued, and weekday peak hour M trips were extended from San Mateo southward to Union City via the Dumbarton Bridge, with stops at Oracle and on Broadway in Redwood City.

In March 2010, due to the persistent economic impacts from the Great Recession, the two bridge route was cut back to only operating on the San Mateo Bridge from Hayward and only on weekdays, with peak hour trips continuing to serve Oracle. A separate route operated directly by AC Transit, DA, would serve the discontinued portion between Newark and Oracle via the Dumbarton Bridge.

In December 2013, due to low ridership, the route extension of the M Line to Oracle was discontinued and the M Line would operate during weekday peak hours only between Hillsdale and Hayward. The DA was discontinued entirely.

In March 2020, due to the initial panic of the COVID-19 pandemic and stay-at-home orders, AC Transit, like many other transit agencies throughout US, dramatically reduced service. The stay-at-home orders not only reduced transit demands, many transit agencies were also concerned about impact of COVID on its workers (and imposed many well intentioned measures like rear door boarding, reducing capacity and blocking out seats for social distancing, and mask mandates). Commute routes like the M were “suspended” with no timetable to return.

As years have gone by since the initial shock-and-awe over the pandemic and COVID-19 has faded into background for most people, AC Transit isn’t in the position to restore the M line due to labor shortage and priority to restore local service (it just restored service on Ashby Ave in Berkeley in Aug 2023 on a trial basis). Meanwhile, schools, offices, and traffic, are gradually returning to normal.

Although public transit is no longer available since March 2020, the gray buses that normally circulate round SFO terminals and parking lots have appeared on 101 south of the Airport and into the East Bay in September 2022. SFO launched a new shuttle for airport workers from Castro Valley to SFO with a stop at Hayward BART. That service is fairly frequent, with half hourly service running almost 24 hours a day. If this service were not restricted to airport workers (not even open to airport customers), it would’ve been the most frequent transit service available in the bridge’s history.

SFO is obviously a major employment center not as much impacted by remote work trend that began at the start of pandemic. People work at the airport around the clock so transit availability throughout the day and even night would be essential. Although BART service is available to SFO from Hayward, it requires a transfer and would take about an hour and 15 minutes one way via Downtown Oakland and San Francisco. The shuttle would only take about 40 minutes. BART is also not available 24 hours a day, and not starting early enough especially on weekends for airport workers.

Besides the SFO operated shuttles, some large employers on the Peninsula and Silicon Valley such as Genentech operate its own employee shuttles from various points in the East Bay to their corporate campuses via the San Mateo Bridge. If you add all SFO and various private shuttles operating presently altogether, it should well exceed the number of public bus trips and passenger loads operated during the highest point in the bridge’s history. However those services are not available to those who don’t employ at those companies or sites.

Reimagine San Mateo Bridge Transit

It think it’s time to reimagine transit for San Mateo Bridge, including whether AC Transit should remain the provider for the service. Throughout the pandemic, Dumbarton Bridge maintained transit service because it was operated by a contractor and has dedicated staff and vehicles. Big agencies like AC Transit had to make political choices between keeping marginal local or commuter service when facing funding or labor constraints. The M line did not get the same high ridership like the U line serving Stanford University. The operating resources that allocated to the M line could’ve used to support not-as-performing local service and could be considered more socially equitable. If the M line is to be contracted out (or merged with the Dumbarton service), the service could be restored sooner.

I suggest the M line, along with Dumbarton service, be managed and governed on a political level, by a new regional entity (call it “South Bay Crossing Transit Authority”) like the Water Emergency Transportation Authority, Transbay Joint Powers Authority, and BART. The current set up of local county based transit agencies tend to align service to county based social welfare programs and doesn’t focus well on regional commuter needs. Workers and job sites aren’t siloed by county lines.

That new agency not only could better manage and promote existing bus services on the two bridges, it could also effectively plan, fund, and build transit facilities including park and ride lots and even large projects like Dumbarton Rail, a project that has been stalled several times since the rail bridge was acquired by SamTrans in the 1990s.

I believe that the SFO shuttle service should be enhanced and open to all. Although it runs nearly 24 hours a day, the shuttle has limited capacity (they are typical transit buses with seats removed for luggage racks) and there’s no long term parking in the East Bay. Shuttle service can be improved by using larger commuter buses with undercarriage storage. Such frequent and low cost long distance shuttle would be similar to the successful LAX FlyAway service in Los Angeles. Additional on-highway stops on 101 (like at 3rd Ave in San Mateo) can be added to improve airport access for Peninsula workers (since off peak and weekend SamTrans 398 service has been discontinued) and non-airport riders just crossing the bridge.

There’s also a need to identify sites for park & ride in the East Bay, especially if the SFO shuttle is open to all and where there’s demand for long term parking. Besides BART stations (which are reserved by BART passengers with exception for SFO shuttle for now), there are two park and ride lots in Castro Valley along I-580, both too far from I-880 or SR-92 for buses to serve effectively. Opportunities for new park & ride in the Hayward area include parking garage at old Hayward City Center, and at Southland Mall.

San Mateo Bridge also lacks dedicated bus or HOV facility on the Peninsula side. On the East Bay, there’s an westbound HOV lane leading to the toll plaza, but no such lane in the eastbound from 101. I believe that it shouldn’t be expensive to place a HOV or bus only on ramp from Foster City to the bridge.

For a long time, the priority for investment on transbay transit has been the Bay Bridge corridor, where it is served by all day transbay bus, BART, and ferries. Despite more than 80% of the bridge traffic has returned post-COVID, transbay transit for southern part of the bay is largely an afterthought. Even with voters approving hikes in bridge tolls to fund transit, light rail extension in East San Jose gets the money (where residents there unlikely pay tolls) supposedly because of its connection to BART in Milpitas, which goes to San Francisco from Oakland. There hasn’t been enough political motivation to make transit more of a solution for San Mateo and Dumbarton corridors. It seems like the politicians prefer to tax those bridge commuters to fund local pet projects outside the corridors. Employers have done much more to implement private solutions on their own dime than any public agency.

One of the problems with past bus routes is that they’re planned with a mindset that riders are not time sensitive and where commuter amenities like park & rides and direct service are deemphasized. When funding becomes limited, such lines often get to cut first since other non-time sensitive alternatives are available, primarily by going via Downtown San Francisco or San Jose.

A well thought out bus service can very well make a dent on transbay commutes on San Mateo Bridge, with all day service to high employment sites, along with easy park & ride. It shouldn’t be hard, and would be much use of dollars and staff resources compared to ideas like the second transbay tube.