101 Express Lanes Construction Update

**Note: Daytime work on U.S. 101 will occur starting the week of November 1st in the City of San Mateo. See below for more details.

Construction Update – Week of October 25th

First Sound Wall Complete! Reconstruction of the section of sound wall along Bayshore Boulevard from Dore Avenue to East Poplar Avenue in the City of San Mateo is now complete, and the section of Bayshore Boulevard adjacent to the sound wall has been reopened to two-way traffic.

Second Sound Wall Nearing Completion: Construction activities associated with relocating the section of sound wall along Bayshore Boulevard from Newbridge Avenue to just past Dakota Avenue in the City of San Mateo are nearly complete. Expect minor construction activities to complete this section of sound wall in the coming weeks.
The section of sound wall on Bayshore Boulevard from Dore Avenue to East Poplar Avenue stands complete

The section of sound wall on Bayshore Boulevard from Dore Avenue to East Poplar Avenue stands complete

Upcoming Daytime Work in the City of San Mateo

Construction crews will install the foundation of a retaining wall on southbound U.S. 101, south of the East Hillsdale Boulevard on-ramp, requiring the intermittent use of a hydraulic hammer. This work will take place from 1:00 PM to 9:00 PM; it is anticipated to take place over 5 non-consecutive working days, currently scheduled to begin on Wednesday, November 4th. Check the “Construction Update” tab on [101express.com]101express.com for schedule updates. Intermittent noise and vibration from the use of a hydraulic hammer as well as other common construction-related sounds such as backup alarms may be anticipated.

In addition, this work may require the closure of two southbound U.S. 101 on-ramps from East Hillsdale Boulevard:

  • Eastbound East Hillsdale Boulevard, Southbound U.S. 101 On-Ramp
  • Westbound East Hillsdale Boulevard, Southbound U.S. 101 On-Ramp

North of Whipple Avenue: Construction activities on U.S. 101 from Whipple Avenue to I-380 (in South San Francisco) will include: continued work in the area near the removed sound walls along Bayshore Boulevard (from Newbridge Avenue to just past Dakota Avenue and from 2nd Avenue to Dore Avenue), all within the City of San Mateo. Additional work will include installing stormwater drainage systems, sign foundations, overhead signs, temporary lighting, and temporary ramp metering; grading; paving; restriping; roadway excavation; landscaping work; and other construction-related activities.

Most of the work will occur on the freeway lanes, shoulders, and ramps, while sound wall work will occur on city streets adjacent to U.S. 101. More information is provided below.

Construction crews placing asphalt in a new section of freeway shoulder
Construction crews placing asphalt in a new section of freeway shoulder

Sound Wall Work: Construction crews working on the sound walls continue to implement periodic traffic control on Bayshore Boulevard (from Newbridge Avenue to just past Dakota Avenue and from 2nd Avenue to Dore Avenue) in the City of San Mateo. Traffic control may occur from 8:00 AM to 5:00 PM, Monday through Friday. Watch for detour signs. After 5:00 PM, the road will be restored to two-way traffic.

Nighttime Freeway Lane Closures: Nightly freeway lane closures may occur on northbound and southbound U.S. 101 from 7:00 PM to 6:30 AM, Sunday night to Friday morning. Due to low traffic volumes, project-related traffic delays are anticipated to be minimal. Caltrans will continue to monitor traffic delays and make adjustments, as necessary.

Freeway Ramp Closures: Temporary ramp closures may occur during the night. Ramp closures could occur in both the northbound and southbound directions of the freeway. However, consecutive interchanges for northbound and southbound ramps will not be closed at the same time.

Nighttime ramp closures: Short-term nighttime ramp closures are possible the week of October 25th (between Sunday night and Friday morning) in/near the cities of Redwood City, San Carlos, Belmont, San Mateo, Foster City, Burlingame, Millbrae, and San Bruno at the following locations (listed from south to north). Changeable message signs near the ramps will have exact closure times and locations.

  • Eastbound Whipple Avenue, Northbound U.S. 101 On-Ramp
  • Northbound U.S. 101, Whipple Avenue Off-Ramp
  • Westbound Whipple Avenue, Southbound U.S. 101 On-Ramp (Closures possible starting at 6:00 PM at this location)
  • Eastbound/Westbound Holly Street, Northbound U.S. 101 On -Ramp
  • Eastbound/Westbound Holly Street, Southbound U.S. 101 On/Off-Ramp
  • Northbound U.S. 101, Northbound Holly Street Off-Ramp
  • Westbound Holly Street, Northbound U.S. 101 On-Ramp
  • Harbor Avenue, Southbound U.S. 101 On-Ramp (Closures possible starting at 6:00 PM at this location)
  • Eastbound/Westbound Ralston Avenue, Southbound U.S. 101 Off-Ramp
  • Westbound Marine Parkways, Northbound U.S. 101 On-Ramp (Closures possible starting at 6:00 PM at this location)
  • Eastbound East Hillsdale, Northbound U.S. 101 On-Ramp (Closures possible starting at 6:00 PM at this location)
  • Eastbound East Hillsdale, Southbound U.S. 101 On-Ramp
  • Westbound East Hillsdale, Southbound U.S. 101 On-Ramp
  • Northbound U.S. 101, Kehoe Avenue On/Off-Ramp (Closures possible starting at 6:00 PM at this location)
  • Eastbound/Westbound 3rd/4th Avenue, Northbound/Southbound U.S. 101 On/Off-Ramp
  • Northbound U.S. 101, Eastbound/Westbound 3rd Avenue Off-Ramp
  • Southbound U.S. 101, Poplar Avenue On/Off-Ramp
  • Northbound U.S. 101, Peninsula Avenue On/Off-Ramp (Closures possible starting at 6:00 PM and lasting until 7:00 AM at this location)
  • Eastbound Millbrae Avenue, Southbound U.S. 101 On-Ramp
  • Southbound U.S. 101, Eastbound/Westbound Millbrae Avenue Off-Ramp
  • Westbound Millbrae Avenue, Southbound U.S. 101 On-Ramp
  • Eastbound/Westbound San Bruno, Southbound U.S. 101 On-Ramp

Nighttime ramp closures:

  • Will be displayed on changeable message signs within the construction zone
  • Will begin after 7:00 PM and reopen by 6:00 AM, unless otherwise noted above
  • Will have detour signs posted

Upcoming Construction (South of Whipple Avenue): Construction activities in the coming weeks on U.S. 101 from San Antonio Road (in Palo Alto) to Whipple Avenue (in Redwood City) will include excavation on the freeway shoulders and other minor construction activities.

Upcoming Construction (North of Whipple Avenue): Construction activities in the coming weeks on U.S. 101 from Whipple Avenue to I-380 (in South San Francisco) will include: continued work on removed sound walls in the City of San Mateo; daytime work in the City of San Mateo; installing overhead signs, temporary concrete barriers, guardrails, temporary lighting, temporary ramp meters, and stormwater drainage systems; grading; roadway excavation; landscaping work; demolishing concrete barrier; and other related construction activities.

All construction activities are subject to change without notice.

For questions during construction, contact the Caltrans Public Information Officer:

Alejandro Lopez at (510) 385-6856 or 101express@dot.ca.gov.

Visit our website at 101express.com for more information about the project. Follow us on Twitter @CaltransD4.

If you would like a copy of a prior construction update, please email 101express@dot.ca.gov.

If you would like a copy of a prior construction update, please email 101express@dot.ca.gov.