US 101/SR 25 Interchange - Phase 1

The existing US 101/SR 25 interchange, located just south of Gilroy in Santa Clara County, is over thirty years old.

It cannot accommodate traffic demands due to rapid growth in commuter, commercial, and recreational traffic that passes through this area. These conditions, coupled with high travel speeds, have resulted in higher than average accident rates in the interchange area, and traffic backups onto southbound US 101.

This Phase 1 project sets the stage for future implementation of the overall interchange reconfiguration slightly north of the current interchange. Phase 1 will...

The existing US 101/SR 25 interchange, located just south of Gilroy in Santa Clara County, is over thirty years old.

It cannot accommodate traffic demands due to rapid growth in commuter, commercial, and recreational traffic that passes through this area. These conditions, coupled with high travel speeds, have resulted in higher than average accident rates in the interchange area, and traffic backups onto southbound US 101.

This Phase 1 project sets the stage for future implementation of the overall interchange reconfiguration slightly north of the current interchange. Phase 1 will accommodate future improvements to US 101, SR 25, SR 152, and provide a connection point at the interchange for a future Santa Teresa Boulevard extension to Castro Valley Road. The proposed Phase 1 project is funded by 2016 Measure B and SB1

Objectives

  • Improve connectivity between US 101 and SR 25
  • Improve traffic operations along US 101 and SR 25 with added ramp storage and signals
  • Enhance safety within the interchange area by reducing ramp backups onto southbound US 101 and provide improved access for safer merges
  • Support the overall future interchange reconfiguration, including US 101 and SR 25 widening, and future SR 152 improvements between US 101 and SR 156

Project Features

Phase 1 will reconstruct the US 101/SR 25 interchange slightly north of the current interchange.

  • Replace the SR 25 two-lane overcrossing with a four-lane overcrossing spanning across US 101
  • Increase the length of the southbound US 101 off-ramp to SR 25 to decrease traffic back-ups onto US 101
  • Upgrade the northbound US 101 ramps to improve exit and merging operations
  • Install new traffic signals at the ramp intersections to improve traffic flow

As additional funding becomes available, future phases of interchange improvements will be scheduled. These future upgrades include converting the interchange to a partial cloverleaf or diamond ramp configuration with potential direct connectors, frontage roads for local and bicycle access, and grade separating SR 25 from the Union Pacific Railroad east of US 101.

The overall project is included in the Valley Transportation Plan (VTP) 2040 Highway Program.

Community Outreach

Quarterly updates are provided to the Mobility Partnership. The Mobility Partnership provides policy oversight and direction to VTA staff and the Council of San Benito County Governments regarding potential mobility improvements between US 101 and I-5 in southern Santa Clara and northern San Benito Counties. 

Online Community Meeting

In case you missed the June 9, 2021, online meeting, watch a recording of the presentation on the VTA YouTube Channel. View the presentation slides here

Frequently Asked Questions

*Last Updated 6/24/2021

  • Is the extension of Santa Teresa Boulevard part of this project?
    • VTA agrees that the Santa Teresa Boulevard extension from Castro Valley Road to State Route 25 is an important feature of the ultimate US 101/ SR 25 interchange. VTA is actively seeking funding from federal grants to be able to develop and implement this project and potentially supplement the project with 2016 Measure B sales tax funds. If successful, the project can begin with the environmental clearance phase in 2022. Please subscribe to the SR 152 Trade Corridor, and the US 101/SR 25 Interchange projects to receive updates on the subject. 
  • Why is the proposed northbound 101 exit to eastbound 25 going under the overpass?
    • ​​​​​To improve safety and comply with design standards, the proposed northbound 101 off-ramps for the US 101/SR 25 Interchange Phase 1 project will be lengthened to provide more deceleration distance before the first sharp curve on the off-ramp as compared to existing conditions. This off-ramp is located next to a protected creek and historical site that cannot be impacted based on environmental approval previously obtained for the project.  Because of these constraints, and to reduce the right of way take and not shift the proposed SR 25 overcrossing further to the north, the northbound off-ramp extends underneath the SR 25 overcrossing before looping back to the intersection with SR 25. 
    • Routing the northbound off-ramp along the south side of the proposed SR 25 alignment would complicate stage construction of the project since that is the area of the existing SR 25 on the embankment that would need to be removed first before building the ramp.  Additionally, it would be difficult to taper this third lane to eastbound SR 25 to the single lane that is required before the Union Pacific Railroad crossing. Both the Phase 1 and ultimate interchange configurations propose signalizing the northbound US 101 ramps/SR 25 intersection to control traffic operations.
  • There is a concern for the closure of Mesa Rd. during and after construction, and the community impact it will cause to farm property and rental property along Mesa Rd. How will this closure, and the project impact those rentals? Will the renters be having to leave?
    • VTA is in the process of finalizing the design and determining right-of-way needs for construction.  Once this has been finalized and approved, VTA will begin reaching out to owners to schedule appraisal inspections. Our current estimate is that appraisals will begin in the Fall of 2021.

How to Reach Us

For more information on this project, please call VTA’s Community Outreach at (408) 321-7575, (TTY) 408-321-2330, or community.outreach@vta.org.

Environmental Documents

The following PDFs are available to view and/or download. The 2013 Final EIR is provided as a full document, or as smaller chapters for your convenience.

2013 Final EIR: Full Document

2013 Final EIR: Cover, Summary, Table of Contents

2013 Final EIR: Chapter 1, Proposed Project

2013 Final EIR: Chapter 2, Affected Environment, Environmental Consequences & Avoidance, Minimization, and/or Mitigation Measures

2013 Final EIR: Chapters 3-6, Comments & Coordination, Responses to Comments on Draft EIR, List of Preparers, Distribution List

2013 Final EIR: Appendices A-G

 

Timeline

Title
Design
Phase Date Range
-
Title
Environmental Update
Milestone Date
Title
Blog: US 101/SR 25 Interchange Project Advancing in Design
Milestone Date
Body

Traffic congestion may be lighter since the start of pandemic-related shelter-in-place orders, but we all know it’s going to come back someday. Read more.

Title
Online Community Meeting: Project Overview & Update
Milestone Date
Body

Watch a recording of the presentation on the VTA YouTube Channel. View the presentation slides here

 

Title
Construction
Phase Date Range
-

Funding

Total Funding
Estimated $100 Million

Map

Subscribe to Updates

Email Address (required) *