SamTrans Pushes Both Transit and Traffic Expansions for Dumbarton Bridge

Bicyclists approach the Dumbarton Bridge from the west. Photo: Jun Seita / Flickr
Bicyclists approach the Dumbarton Bridge from the west. Photo: Jun Seita / Flickr

SamTrans officials presented an update on the agency’s Dumbarton Transportation Corridor Study at two community meetings this week, fielding questions from residents on ways the agency is hoping to provide better transit service over the Dumbarton Bridge. Facebook donated $1 million to the agency in January for the transportation study, which it hopes can expand commute options for its workers and cut traffic near the company’s Menlo Park headquarters on Willow Road.

While the long-envisioned Dumbarton Rail project to rebuild a cross-Bay rail bridge to carry passenger trains between Redwood City Caltrain and Union City BART is still alive in the study as a long-term (2030) option, a more frequent and expanded Dumbarton Express bus service tops the agency’s list as the most effective improvement that can be funded and implemented within five years.

“The cost of the [rail] bridge rehab ranges from $330 to $348 million in 2011 dollars, which would be up using 2016 dollars,” said Principal Planner Melissa Reggiardo at Monday’s community meeting in Newark.

An expanded Dumbarton Express bus service would consist of two routes connecting the Union City BART Station to Caltrain stations in Redwood City, Mountain View, and Sunnyvale. Physical upgrades to speed bus travel might include transit-signal priority and queue jump lanes at intersections, direct access on-ramps to the highway for buses and carpools, and possibly even new bus-only lanes.

“Travel times are painfully slow. People will only get on [the bus] if the ride is sped up and a little more competitive with auto travel. We see that as key,” said Reggiardo.

SamTrans staff present which transit and traffic expansion options are still under consideration in the agency's Dumbarton Corridor Transportation Plan at a community meeting in Newark. Photo: Andrew Boone
SamTrans staff present transit and traffic expansion options that are still under consideration at a community meeting in Newark. Photo: Andrew Boone

But SamTrans is also considering major auto traffic capacity expansions on the Dumbarton Bridge itself and on the highway approaches to the bridge. The agency assumes that capacity expansions will alleviate rush-hour traffic congestion and allow buses to travel faster, rather than inducing demand for more driving over the bridge and jamming it up with even more traffic.

SamTrans says that by 2020, several alternative lane configurations could be installed and will be studied in detail for their impact on traffic flow: reversible center lanes to provide four lanes in the peak-travel direction, carpool lanes, and express (toll) lanes. The Ardenwood Park & Ride lot could be expanded again for more cars, though it was rebuilt from 100 to 350 parking spaces in 2009.

A number of ways to speed access for drivers through the Dumbarton Bridge toll plaza on its east end are in the new study, including longer toll lanes to fit more traffic, “open road tolling” which would remove the toll booths, and constructing new direct access on-ramps for carpool and buses to connect Newark Boulevard and Highway 880 to the toll plaza.

Despite the study’s officially stated goals to pursue cost-effective improvements that enhance mobility, minimize environmental impacts, and protect low-income and minority populations, even bigger highway expansions costing hundreds of millions of dollars are on the table.

Reversible lanes separated by a movable median barrier on the Dumbarton Bridge would allow more rush-hour auto traffic in the peak direction (west in the morning, east in the evening). Image: SamTrans
Reversible lanes separated by a movable median barrier on the Dumbarton Bridge would allow more rush-hour auto traffic in the peak direction (west in the morning, east in the evening). Image: SamTrans

“We’re looking at grade separations of Bayfront at Willow and University on the Peninsula, and we’re looking at Willow Road express lanes from the previous 2020 Gateway Study,” said Reggiardo. “We would likely be looking at some sort of depressed express lanes in that area.”

That 2008 study [PDF] proposed “a depressed trench structure below Willow Road… beginning with underground portals at Highway 101 and ending with underground portals on Bayfront Expressway east of Willow Road.” This one-mile underground roadway expansion would cost an estimated $373 million in 2006 dollars and require the relocation of the Hetch-Hetchy water pipelines.

Grade separating the Bayfront Expressway intersections of Willow Road and University Avenue would require new overpasses and ramps, consuming even larger areas for auto traffic and creating additional lanes for people walking and bicycling to cross.

The new Dumbarton Corridor Study also considers a new bike/ped path and possibly bus lanes along the south side of the Dumbarton Rail tracks between Redwood City Caltrain Station and Willow Road, concepts favored by Facebook to deliver workers to its growing headquarters. SamTrans reports that a 100-foot wide swath of lane is available on the south side of the tracks, although it’s unknown if any obstructions would prevent the installation of a path or bus lanes.

SamTrans planners will analyze the alternatives selected for more detailed review and present their recommendations along with a funding plan for a set of preferred improvements in April 2017.

  • Richard Mlynarik

    How grand to be a SamTrans planner!

    Cratering bus ridership for decades.

    Fiscally catastrophic and utterly unambiguously fraudulent (ridership, revenue, capital cost, operating cost) BART extension.

    Fail to undertake any meaningful Caltrain upgrades for three decades.

    Collude in shifting Caltrain and Dumbarton Rail funding to insane and fraudulent East Bay BART extensions.

    Ever-increasing VMT.

    Ever-widening freeways.

    And you get to “study” transit again, and again, and again, and again. Can’t wait for the “conclusions” of this “study” to be “released” in 2017, and then again in 2020, and 2025, and 2028, and 2030, and beyond. It’s going to be great!

  • Joseph

    Americas finest transportation planning professionals.

  • murphstahoe

    I would unblock RichLL just to see him have an argument with Richard Mylnarik

  • I’m concerned that cyclist in the photo isn’t passing safely, but is instead riding in the opposing traffic lane in an unsafe and illegal manner.

  • Jeffrey Baker

    I’m seen some wasteful proposals in 20 years of living here, but this one is really bad. They could just raise the toll at no internal cost, with large external benefits. The toll was last raised to $5 in 2010. Even if it were to only track CPI it would now be $5.50, but given the congestion it should be doubled at peak hours, and established in the eastbound direction, if this presentation had been written by serious people. But, since the presentation includes hyperloops, monorails, and autonomous-vehicle-only lanes, I take it that it was written as a joke.

  • David

    Ridership cratering is typical of the region and not just SamTrans. People simply aren’t taking traditional bus service with the frequency they used to. Also, the BART extension was entirely political, so you can’t blame them for that either.

  • David

    Yeah, let’s raise the tolls on working stiffs who are just trying to get a paycheck. Let’s not do anything about the residents and politicians of San Mateo County that are unwilling to build the housing necessary to support the job market located there. I have a better idea… Let’s move all those jobs from Menlo Park to the East Bay so this becomes a non-issue.

  • crazyvag

    Dumbarton bridge is one place where tolling should be bi-directional given that many drive 880-237 heading west and take Dumbarton bridge east for free.

  • RichLL

    If the idea is to “ease congestion” then getting rid of toll booths is a better solution than hiking tolls. So SamTrans is correct to explore the tech solutions to doing that, as GG Bridge has already done. The toll booths on the Bay Bridge is still a major bottleneck, FasTrak notwithstanding.

    Raising tolls discriminates against low income folks and minorities, breaching one of SamTrans’ key objectives, as the article clearly states:

    ” the study’s officially stated goals to pursue cost-effective improvements that enhance mobility, minimize environmental impacts, and protect low-income and minority populations”

    But the “joke” here is surely “depressed express lanes”, and reminds me of the “Depressed Highway” in my beloved home state of New Jersey”.

  • RichLL

    How many? If too many do that then surely 880/237 will be much slower going west, motivating people to pay the toll for a quicker drive.

  • murphstahoe

    When I think Facebook, I think “working stiff”

  • murphstahoe

    to save $5? Probably costs an extra $10 in gas and hundreds of dollars in time

  • David

    Facebook employees get great benefits, including an incentive to live close to work and shuttle bus service. However, let’s not forget all the other jobs that are involved, such as in support industries like food service. The world (and this part of San Mateo County) is much bigger than Facebook itself.

  • RichLL

    How much do the cleaners at FaceBook make?

    Are the only people driving over that bridge making 150K a year or more?

  • Following that logic, wouldn’t tolling in the other direction push more traffic to 880-237?

    Is the traffic heading east really denser than heading west overall for the day?

  • crazyvag

    Well, if Toll is $6, but bus is $4 then I think it’s an overall win. There will always some that due to circumstances can’t take advantage of it, but bridges have the upside of creating a corridor that is easier to service with buses…

  • Or maybe have the ability to toll either direction and apply it to the direction most affected by rush hour.

  • Rogue Cyclist
  • Jeffrey Baker

    This line of argument isn’t really based on facts. Driving costs 75 cents a mile and wasting an hour in traffic is not something that working stiffs can afford. People in the lowest quintile of income are the ones who benefit the most from reliable bus service and who worry the least about having to pay tolls.

  • David

    That is region-wide, and most of the increase is on BART. Suburban bus operators like SamTrans, VTA, and Golden Gate are in free fall.

  • neroden

    Muni continues to burst at the seams. Build actual train service, people take it…


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