Water Transmission Main Project, Phase 2


Start: July 2019

Ends: (approx) November 2019


McMinnville Water and Light (MW&L) has provided safe and dependable drinking water to McMinnville area residents and businesses for over 100 years. In 2010, MW&L expanded the Water Treatment Plant capacity to 22 million gallons per day (mgd).  Due to transmission main conveyance restrictions, 22 mgd currently cannot be conveyed through the water transmission system. The finished water transmission system is currently comprised of a 24-inch ductile iron main installed in the late 1960’s, and an older pipeline comprised of 14-inch asbestos cement pipe and 16-inch welded steel pipe installed in the late 1940’s. MW&L has implemented a plan to replace the 16-inch transmission main in a phased approach. The first phase of the project was completed in 2014 when 2,200 feet of 36-inch welded steel was installed through a new tunnel from the outlet of the Water Treatment Plant to the Panther Creek valve station.

Construction for Phase 2 began in July and is anticipated to extend through November 2019. Phase 2 replaces approximately 7,000 feet of existing 16-inch transmission main between Luoto and Sitton interties with 36-inch ductile iron pipe. This segment of transmission main experienced a series of leaks in recent years. Critical project elements include:

  • New intertie at NW Fir Crest Road due to the ease of accessibility
  • Installation of all necessary air valves and blow-offs
  • Installation of approximately 7,000 feet of 3-inch electrical duct bank including vaults to facilitate future installation of electrical or fiber optic cable
  • Installation of approximately 7,000 feet of 36-inch ductile iron water transmission main

Stantec Consulting Services, Inc. was contracted to design Phase 2 of the project. The construction project was awarded to Moore Excavation from Fairview, Oregon for a total contract price of $3,998,815.00.