Information provided by Caltrans District 5. Lea este articulo en español aquí.

VTA is continuing construction on the US 101/SR 25 Interchange Phase 1 Improvements Project. South County drivers should prepare for overnight ramp closures beginning Wednesday, March 11. 

Nightly Ramp Closures

Beginning Wednesday, March 11, 2026
8:00 PM – 6:00 AM (Overnight Only)
Closures will continue into the following week. 

The following ramps will be CLOSED overnight:

  • Southbound US 101 On-Ramp from SR 25
  • Southbound US 101 Off-Ramp to SR 25

Detours will be in place. Motorists are advised to:

  • Allow extra travel time
  • Follow posted detour signs
  • Drive cautiously through the work zone

All ramps are expected to reopen by 6:00 AM each morning. 

Detour Routes

Detour Route for Overnight closure of the US 101 northbound on-ramp:

Continue north on SR 25

  • Follow detour signs onto Monterey Road
  • Reconnect to southbound US 101 at the Monterey Road interchange

Detour Route for Overnight closure of the US 101 southbound off-ramp:

  • Continue South on US 101 to Betabel Road
  • Betabel Road to Northbound US 101
  • Northbound US 101 to Southbound SR 25

What Work Is Taking Place?
Day Time Work:

  • Crews will be working on building the new bridge.
  • They’ll be doing major structural work on the new connector roadway.
  • Workers will install steel reinforcing bars (rebar) and set up forms to pour concrete.
  • Construction will continue on the bridge foundations and support columns.

Night Time Work: 

  • Crews are digging dirt and soil from the hillside located west of the southbound Highway 101 on-ramp.
  • The excavated material is being loaded onto trucks.
  • The trucks are moving the dirt to the construction area for the new SR 25 Separation Bridge.
  • The dirt is being used to build up the raised roadway (embankment) that will support the new bridge.

What Drivers Should Expect:

  • Overnight detours near the US 101/SR 25 interchange
  • Possible nighttime construction noise
  • Visible crane and bridge construction activity

Stay Informed:

Traffic conditions may change due to weather or construction. For updates, visit https://www.vta.org/projects/us-101sr-25-interchange-phase-1 | Contact VTA Community Outreach at (408) 321-7575 or Email community.outreach@vta.org.