Caltrain: 25th Avenue Grade Separation Project

25th Grade Separation Project renderingProject Description:

Caltrain, in cooperation with the City of San Mateo, will raise the tracks and slightly lower the road (grade separate) at E. 25th Avenue in San Mateo. 

This will improve safety for both motorists and pedestrians, and it will reduce local traffic congestion in San Mateo. 

In addition, the project will create new east-west street connections at 28th and 31st Avenues; and as part of the project improvements, Caltrain will build a new elevated Hillsdale Station with updated amenities at E. 28th Avenue. 

The track raise in turn provides the opportunity to complete east-west street connections at 28th and 31st Avenues in conformance with the San Mateo Rail Corridor Transit Oriented Development Plan.

The Hillsdale Caltrain Station will also be relocated northward between 28th and 31st avenues as part of the improvements.Hillsdale Station rendering - May 2019

Planning for the Hillsdale Station Closure

Too early to plan your daily commute in December? Think again. As part of the 25th Grade Separation Project, Caltrain will need to temporarily close Hillsdale Station from December 2019 to June 2020. During the closure, only downtown San Mateo Station and Hayward Park Station will remain open. Service will be increased to Belmont Station, and Caltrain is enhancing its shuttles between Belmont and Hillsdale, not to mention the SamTrans bus along El Camino Real. Shuttles and bus service will be part of your train ticket between Belmont and Hillsdale during the closure. Have you signed up for 25th Grade Separation Project email updates? Click here to add your email.

Why Belmont Station? 

When planning for the station closure, Caltrain examined moving service to Hayward Park Station. Only a few locations between San Francisco to San Jose allow bullet trains to pass safely. Hayward Park Station does not provide an opportunity to let the express trains pass, and added stops there would cause system-wide delays. Thus, Belmont Station was selected as a temporary station while Hillsdale Station is closed for six months. Another factor considered was parking. Hillsdale Station has approximately 518 spaces available that are often at 100 percent occupancy. Hayward Park Station has 213 spaces but due to private development are now at approximately 140 available parking spaces. See Caltrain's most recent presentation to San Mateo’s Sustainability and Infrastructure Commission where the selection of Belmont Station was discussed in more detail. 

Outreach for the station closure -- including information about the added shuttles from Belmont Station for Hillsdale Station riders -- will begin in earnest in July, and a robust FAQ should answer other questions including schedule, bike accessibility on shuttles, and more. 

What's the Latest? 

Caltrain launched its first project-related Virtual Town Hall on Wednesday, July 31. You can watch an archived version of the interactive community meeting by clicking on Caltrain's YouTube page. 25th Grade Time-Lapse - July 2019 Opens in new window

In July 2019, the new rail bridge was installed at E. 25th Avenue at Delaware Street. Click here to see a 20-second time-lapse of the overnight work. 

Starting July 15, PG&E will need to close both lanes of Pacific Avenue (between S. Delaware Street and Hillsdale Boulevard) for up to seven weeks to complete gas line work that the utility started in October. Access to the Hillsdale train station and sidewalks will remain open during this temporary street closure. In addition, PG&E will also close a single lane of traffic, as needed, between 25th and 28th avenues to complete its work. Traffic control signs will be in place in the community. For questions regarding this work, call 650-598-7416, Pipeline Safety & Gas System Help Line: 1-800-743-5000 or visit

Recent Presentations

Caltrain made its latest project presentation to San Mateo City Council on July 15, 2019. Click here to view the presentation (starts at hour 2:30). On May 8, 2019, Caltrain presented its latest project update to San Mateo's S&I Commission (starts at minute 08:50).

How can you get project updates?

For weekly construction updates and register for the weekly email, visit Caltrain's project website.