2020-09-20-101-express-update

**Note: Extended weekend ramp closures may occur beginning Sunday, September 20th. Nighttime work may occur near the removed sound wall along Bayshore Boulevard from Newbridge Avenue to just past Dakota Avenue in the City of San Mateo. See below for more details.

Construction Update – Week of September 20th 

 South of Whipple Avenue: This week, construction activities on U.S. 101 from San Antonio Road (in Palo Alto) to Whipple Avenue (in Redwood City) will include: work on overhead signs and paving. This work will take place on the freeway median and ramps, but no delays are anticipated. Short-term nighttime ramp closures are possible this week at locations south of Whipple Avenue. Planned ramp closure locations are provided below in the “Freeway Ramp Closures” section.

North of Whipple Avenue: Construction activities on U.S. 101 from Whipple Avenue to I-380 (in South San Francisco) will include: extended weekend ramp closures, as noted below; continued work on the removed sound walls along Bayshore Boulevard (from Newbridge Avenue to just past Dakota Avenue, from 2nd Avenue to Dore Avenue, and from Dore Avenue to East Poplar Avenue), all within the City of San Mateo. Additional work will include installing storm drainage systems, sign foundations, and permanent concrete barriers; electrical service work; removing and placing temporary concrete barriers; roadway excavation; restriping; and other related construction 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.

101 Express Roadway photo

Construction crew excavating earth adjacent to U.S. 101

Extended Weekend Ramp Closures 9/20- 9/21

Beginning Sunday, September 20th, extended weekend ramp closures may occur at ramps in/near the cities of Belmont and San Carlos, in order to facilitate drainage system construction. Closures would be for an approximate 24-hour period and are scheduled to begin after 7:00 AM on Sunday and end by 7:00 AM on Monday. Detour signs will be posted. In addition, changeable message signs will indicate exact closure times and locations. Extended weekend ramp closures may occur at the following locations:

  • Southbound U.S. 101, Eastbound/Westbound Ralston Avenue On-Ramp
  • Southbound U.S. 101, Harbor Boulevard Off-Ramp
  • Southbound U.S. 101, Collector Ramp between Ralston Avenue Off-Ramp and Harbor Boulevard Off-Ramp

Sound Wall Work: Construction crews continue to implement one-way traffic control periodically on Bayshore Boulevard (from Newbridge Avenue to just past Dakota Avenue, from 2nd Avenue to Dore Avenue, and from Dore Avenue to East Poplar Avenue) in the City of San Mateo. One-way traffic control may occur from 8:00 AM to 5:00 PM, Monday through Friday. During this time, northbound traffic will remain on Bayshore Boulevard while southbound traffic will be detoured. Watch for detour signs. After 5:00 PM, the road will be restored to two-way traffic.

101 Express sound wall 7

The rebuilt sound wall on Bayshore Blvd from Dore Avenue to East Poplar Avenue in the City of San Mateo

First Sound Wall Nearing Completion: Construction activities associated with removing and relocating the sound wall along Bayshore Boulevard from Dore Avenue to East Poplar 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.

Nighttime Work Near Removed Sound Wall: Beginning the week of September 20th, construction crews will be working intermittently on U.S. 101 near the removed sound wall along Bayshore Boulevard from Newbridge Avenue to just past Dakota Avenue in the City of San Mateo. Construction activities will include: roadway excavation, pouring concrete, paving, and installing a new storm drainage system. Nearby residents and travelers may see construction crews from 8:00 PM to 5:00 AM. This work may include noise and vibration from roadway excavation as well as other common construction-related sounds such as back-up alarms. Work is anticipated to begin after 8:00 PM on Sunday, September 20th and conclude the week of October 11th, and will be intermittent throughout the week.

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 September 20th (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). Signs near the ramps will have exact closure times and locations.

North of Whipple Avenue:

  • Northbound Whipple Avenue Off-Ramp
  • Westbound Whipple Avenue, Northbound U.S. 101 On-Ramp (Closures possible starting at 6:00 PM at this location)
  • Westbound Whipple Avenue, Southbound U.S. 101 On-Ramp (Closures possible starting at 6:00 PM at this location)
  • Westbound Whipple Avenue, Northbound U.S. 101 On-Ramp
  • Eastbound Whipple Avenue, Northbound U.S. 101 On-Ramp
  • Eastbound Whipple Avenue, Southbound U.S. 101 On-Ramp
  • Southbound Brittan Avenue On-Ramp
  • Eastbound/Westbound Brittan Avenue, Southbound U.S. 101 Off-Ramp
  • Eastbound/Westbound Holly Street, Southbound U.S. 101 On/Off-Ramp
  • Eastbound/Westbound Harbor Avenue, Southbound U.S. 101 On/Off-Ramp
  • Southbound U.S. 101, Eastbound/Westbound Ralston Avenue On/Off-Ramp
  • Westbound Ralston Avenue, Southbound U.S. 101 On-Ramp
  • Eastbound/Westbound Fashion Island Boulevard, Southbound U.S. 101, On-Ramp
  • Westbound Route 92, Southbound U.S. 101 Connector Ramp
  • Eastbound Route 92, Northbound U.S. 101 Connector Ramp
  • Southbound U.S. 101, Eastbound/Westbound Route 92/Fashion Island Boulevard Connector Ramp
  • Northbound Kehoe Avenue On/Off-Ramp (Closures possible starting at 6:00 PM at this location)
  • Eastbound/Westbound 3rd Avenue, Northbound U.S. 101 Off-Ramp
  • Eastbound/Westbound 3rd/4th Avenue, Southbound U.S. 101 On-Ramp
  • Southbound Poplar Avenue On/Off-Ramp
  • Northbound Peninsula Avenue On/Off-Ramp (Closures possible lasting until 7:00 AM at this location)
  • Eastbound/Westbound Broadway & Old Bayshore, Southbound U.S. 101 On-Ramp
  • Northbound Broadway & Old Bayshore On/Off-Ramp
  • Northbound U.S. 101, Eastbound/Westbound Millbrae Avenue On/Off-Ramp
  • Southbound U.S. 101, Eastbound/Westbound Millbrae Avenue On/Off-Ramp
  • Eastbound Millbrae Avenue, Southbound U.S. 101 On-Ramp
  • Southbound SFO Off-Ramp
  • Northbound Airport Boulevard On-Ramp
  • Eastbound/Westbound San Bruno Avenue 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

City Streets: In addition to the sound wall activities described above, electrical service work to connect power to overhead signs and freeway lighting will occur on city streets in the cities of San Mateo and South San Francisco. Nearby residents and travelers can expect to see crews from 8:00 AM to 5:00 PM, Monday through Friday. This work will produce intermittent low vibrations and construction vehicle noise, and will also require temporary lane closures (one-way traffic). Cones and flaggers will safely direct traffic around closures. Electrical service work may occur near the following intersections:

Folkstone Avenue and South Amphlett Boulevard in the City of San Mateo
Shaw Road and San Mateo Avenue in the City of South San Francisco

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: storm drainage structure installation. This will take place on the freeway shoulders.

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; installing sign foundations, permanent concrete barriers and storm drainage systems; placing temporary concrete barriers; grading and paving; restriping; electrical service work; roadway excavation; 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.

  • September 13, 2020 Update