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Basin 2 & 3 Pipe Capacity Improvements – El Camino – South Project

Project Type: 


Approximate Construction Start & End Dates:

October 2023 – March 2024

Project Status:

The final design phase is underway and is expected to be complete in late 2021.

Project Location:

  • El Camino Real from north of W Hillsdale Blvd southwards to W 36th Ave.
  • W 36th Ave between El Camino Real and Colgrove St.
  • Colgrove St between W 36th Ave and Darcy Ave.
  • El Camino Real between W 38th Ave and W 41st Ave.

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 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 manholes and at the wastewater treatment plant. These overflows contaminate city streets, creeks, lagoons, beaches, and San Francisco Bay.

The Basin 2 & 3 package of conveyance improvements includes four independent pipe upgrades that total approximately 16,000 feet of pipe, including new relief sewers and extensions and size increases to existing lines. The upgrades will reinforce the system, helping to reduce sewer overflows.

This El Camino – South Project will reconstruct new gravity sewer relief pipelines and new diversion structures and will upsize existing pipelines to eliminate sanitary sewer overflows (SSOs) in the project area.

Notifications will be sent ahead of construction to alert property owners and occupants prior to the start of construction.

Environmental and Permitting Documents:

In Progress

Engineer Firm Name:


Constructor Name: