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Basin 1a Pipe Capacity Improvements

Map of project location.Project Type: 

Collection System

Approximate Construction Start & End Dates:

Construction began in February 2019 and was completed in February 2020

Project Location:

N. Idaho St from Monte Diablo Ave to Tilton Ave; El Camino Real from Warren Rd to State St, then down State St and Highland Ave to E Poplar Ave; Cypress Ave from S Bayshore Blvd to S Norfolk St.

Project Description:

The purpose of the Basin 1a Collection System Improvements project is to provide wet weather capacity assurance in the sewer collection system by increasing sewer pipe capacity to manage peak wet weather flows and prevent sanitary sewer overflows and help meet regulatory requirements. Basin 1a, located in northwest San Mateo, consists of four pipeline projects. The total length of new pipe to be installed is approximately 4,320 feet. These projects were determined to be necessary to prevent sewer overflows based on hydraulic modeling performed on the system. The projects include:

  • El Camino Relief: Enlarge 253 feet of 12-inch pipe to 15-inch pipe.
  • El Camino Real/Poplar Relief: Install 2,579 feet of new 15-inch diversion pipe.
  • N. Idaho Street Relief: Enlarge 660 feet of 15-inch pipe to 24-inch pipe.
  • Cypress Avenue Relief: Enlarge 826 feet of 10-inch pipe to 18-inch pipe.

Environmental and Permitting Documents:

Caltrans permit; National Pollutant Discharge Elimination System permit; Bay Area Air Quality Management District permit.

Engineer Firm Name:

Woodard & Curran

Constructor Name:

Cratus, Inc.