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El Camino Real Sewer Capacity Improvements

Project Type: 

Conveyance – Basin 2-3 Collection System Improvements

Approximate Construction Start & End Dates:

Spring 2024 – Spring 2025

Project Status:

As part of our 10-year plan to improve San Mateo’s overall wastewater system and better manage flooding, the El Camino Real Sewer Capacity Improvements Project will begin the week of April 1, 2024, with Area 1 construction on Flores Street between W 25th and 28th Avenues.

Construction will occur weekdays (Mon-Fri) between 8 AM and 5 PM and is expected to continue on Flores St for approximately seven weeks. (NOTE: construction schedules and traffic patterns are subject to change.)

When traveling through this area, you may experience temporary road and parking closures, with flaggers controlling traffic. Please allow extra time in your travel plans to accommodate these temporary changes.

Project Locations:

The project work will be performed in three areas.

Area 1:

  • W 25th Ave at El Camino Real
  • Flores St between W 25th Ave and 28th Ave
  • 28th Ave between Flores St and Juniper St
  • Juniper St between 28th Ave and 29th Ave

Note: Work on 28th Avenue and Juniper Street will be performed during the school summer holiday period to minimize disruption to community.

Area 2:

  • El Camino Real southbound from north of Hillsdale Intersection to W 36th Ave
  • 36th Ave between El Camino Real and Colegrove St
  • Colegrove St between 36th Ave and W 39th Ave

Area 3:

  • El Camino Real southbound between W 38th Ave and W 42nd Ave

Note: work on El Camino Real will be performed during the night shift to minimize disruption to community.

El Camino Real Areas 1, 2, and 3 location map.

Project Description:

The purpose of the Basin 2 & 3 Collection System Upgrade is to improve the ability of the overall wastewater collection system to manage sewer flows during heavy seasonal rainfall. These improvements will help prevent sewer overflows, as well as help the City comply with regulatory requirements. During heavy rains, the wastewater collection system capacity is overwhelmed by the amount of rainwater that enters the system through infiltration and inflow. This causes sewer overflows at locations around San Mateo, such as at manholes. These overflows contaminate city streets, creeks, lagoons, beaches, and the San Francisco Bay.

The El Camino Real Sewer Capacity Improvements project involves installation of sewers that total approximately 7,800 linear feet of pipe, including new and upsized relief sewers and installation of manholes. The upgrades will reinforce the system with additional capacity, helping to reduce sewer overflows.

Separate notifications will be sent prior to the start of construction to alert property owners and occupants.

Potential temporary construction impacts may include:

  • Parking restrictions and lane closures – only in work zones
  • Driveway access restrictions – only in work zones
  • Detours when working night shift on El Camino Real
  • Construction noise, vibration and dust
  • Potential sewer service disruptions – only for short duration

We thank you for your continued patience and cooperation as we make steady progress toward the completion of our sewer system improvements.

Clean Water Program staff hosted a virtual community meeting on Sept. 25, 2023 to update residents about the project; please click here for the recording of the ECR Virtual Community Meeting.

More information about the project, including anticipated construction activities, timeframes, and temporary impacts for each work area, can be found on our Presentations page.

Key Project Contact:

CWP Project Manager: Makarand Pendse, 1-925-392-3726,