Mountain View's plans to revamp a complex intersection and separate streets from the Caltrain crossing have hit a snag, with construction now expected to begin long after a spike in train service clogs up traffic.
The Rengstorff Avenue grade separation project proposes depressing the intersection of Rengstorff and Central Expressway by 20 feet, separating the roadway from the Caltrain tracks and preventing traffic on Rengstorff from coming to a standstill while trains pass. The hope was that the project would receive swift approval and construction could begin in 2024.
That timeline has since been discarded. The preliminary design of the project and environmental clearance was set to be done in spring 2021, but that work has yet to be complete and likely won't be done until January 2022. City officials say the delays lie with Caltrain, which has cited "project management staffing shortages," according to city spokeswoman Lenka Wright. The earliest construction can begin is now 2025, she said.
Caltrain officials say the project did experience some staffing turnover earlier this year, but that the problem has since been resolved. The transit agency disputes that the staffing shortages lead to a delay in the overall project schedule, and said that the start date of construction has not changed.
Caltrain expects the preliminary design for the project will be done in December, and that the agency still needs to do traffic studies and geotechnical investigations, according to Dan Lieberman, public affairs specialist for Caltrain. The agency also awaits final approval from the Federal Transit Administration and State Historic Preservation officials, who are required to sign off on the project as part of environmental clearance.
Despite the delays, Mountain View is still way ahead of the pack. The cities of Palo Alto and Menlo Park are still vetting design alternatives, whereas Mountain View has been settled on the grade separation design since 2014.
The plan involves two years of construction to lower both Rengstorff Avenue and Central Expressway below the train tracks, which would include significant changes to nearby streets that connect to Rengstorff. Crisanto Avenue would dead-end to traffic at Rengstorff, and the Shell gas station across the street would need to be removed. Despite its close proximity to the tracks and the intersection, the La Plaza Market will continue to operate at its current location, though the parking lot will be completely redone.
Leland Avenue, rather than being closed off to traffic, will snake around the new La Plaza parking lot in order to connect with Rengstorff Avenue.
For years, the proposed grade separation project couldn't proceed because there was no way to pay for it. Now the city is expected to receive $175 million in funds from VTA's Measure B sales tax, which passed in 2016 but was held up by a lawsuit until late 2018. The city has yet to update the cost estimates for the Rengstorff Avenue grade separation project, but previous estimates found it was going to cost about $150 million.
In order to shore up cash to pay for the project, the city is also applying for federal and state grants, and could also tap into local sources like the city's business license tax, which generates millions of dollars annually and must be used primarily for transportation improvements.
Grade separation has been a huge priority for Peninsula cities in recent years and now carries with it a sense of urgency. With Caltrain electrification on the horizon, trains will be passing by at greater frequency and causing significant traffic problems at any existing at-grade crossings. The current level of train service is 70 trains per weekday, which is causing the crossing gates to come down and block traffic for 70 minutes per day, said Joy Houghton, associate civil engineer for the city, at a Nov. 2 community meeting.
Once Caltrain electrification is complete, that number is expected to spike to 174 trains per weekday, causing the crossing gates to be down for about three hours per day, Houghton said. The modernization program was intended to begin in 2022, but has since been pushed out to 2024 -- later than anticipated, but still before Rengstorff Avenue will be separated from the tracks.
Construction, once it begins, will include nighttime work, shifting traffic lanes and roadway closures at the heavily used intersection. Though Rengstorff will be closed at both Central Expressway and Stanford Avenue during construction, traffic along Central Expressway will never be fully blocked off, said Matt Korve, project manager of the engineering firm Aecom. At least one lane will be open in each direction at all times, he said.
During the community meeting, Caltrain officials were already cautioning that the city's original timeline was pretty tight and reflected the quickest path toward construction. Pamela Kwan, senior project manager for Caltrain, described it as a best-case scenario, and said that environmental clearance takes at least a year.
"There are just some steps that we need to make sure that we do our due diligence to make the design compatible with construction," Kwan said.