36-inch Transmission Main Replacement Project

Background & Objectives

The 36-inch transmission main is a critical component of Sweetwater Authority’s water system. The pipeline connects water sources at Sweetwater Reservoir/Perdue Water Treatment Plant to the Authority’s distribution system. The most critical sections of the pipe, some of which are almost 100 years old, have reached the end of their service life and must be replaced to maintain reliability.

36-inch transmission main pipeline

Project Overview

The 36-inch Transmission Main Replacement Project involves:

  • Installation of about three miles of new transmission main
    • 15,000 feet of 36-inch welded steel pipeline
    • 3,100 feet of 48-inch welded steel pipeline
  • Retirement of about three miles of outdated transmission main
  • Realignment of pipe segments at the Bonita Golf Course and the Chula Vista Golf Course, including a nearby condominium complex

Temporary Impacts

  • Traffic control
    • Construction will avoid peak traffic times at critical intersections
  • Temporary trail access impacts near the Bonita Golf Course and the Chula Vista Golf Course
    • Construction schedule will avoid high trail usage season and limit daily impacts to daytime construction hours
  • Installation of pipeline segment at the Chula Vista Golf Course and Bonita-Sunnyside Library parking lot

Estimated Timeline

  • November 2018 - Adoption of environmental documents 
  • June 2019 - Construction starts
  • December 2020 - Construction completed

Project Location

All pipeline replaced during this project is located within the Bonita Valley. See detailed project map here.

Contact the project team:

Phone: 619-409-6751 

Email: 36MainReplacement@sweetwater.org