Fernhill Reservoirs 1 & 2

Fern Hill Facts

  • The JWC stores 40 million gallons (MG) of treated drinking water on Fern Hill. These 20 MG reservoirs are two of the largest potable water tanks in Oregon.
  • Fernhill Reservoir #1 was first completed in 1982 at a cost of $3.3 million.
  • Fernhill Reservoir #2 was completed in 2006. Including rehabilitation of Reservoir #1, the project cost was $17.4 million.
  • Reservoir #2 is wrapped in 141 miles of cable—that’s enough to stretch from Fernhill all the way to Cottage Grove, Oregon. The cable machine wrapped the reservoir at a rate of 2 MPH.
  • Prior to its recent rehabilitation, Reservoir #1 had never been taken off-line in 25 years. Occasional inspections on the tank were performed by specially-trained scuba inspectors.


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Fern Hill Dedication (Past Event)

The Joint Water Commission (JWC) dedicated its new $17.4 million Fern Hill Reservoir #2 and rehabilitated Reservoir #1 on September 13, 2007. The event also marked the 30 year anniversary of the original Joint Water Treatment Plant.

The celebration was unique in that it was held atop Fernhill Reservoir #2. Tim Erwert, Hillsboro City Manager and JWC General Manager at the time, told those in attendance that staging the Dedication on top of the reservoir “Signifies the goal of the JWC to stay on top of the many issues affecting the water industry today – including growth and supply issues, water quality issues, environmental issues – and emergency issues.”

Prior to its recent rehabilitation, Reservoir #1 had been in continual service – providing storage and head pressure to Washington County for 25 years. Occasional inspections on the tank were performed by specially-trained scuba inspectors. After Reservoir #2 was brought on line in September 2006, the older tank finally received a well-deserved rest while it was upgraded to current seismic code and strengthened to match its newly-constructed twin.

The construction of Fernhill Reservoir #2 required 1.6 million pounds of rebar and 8500 cubic yards of concrete. Nearly 140 miles of cable was wrapped around the tank – enough to stretch from Fern Hill, which is located south of Forest Grove, all the way south of Eugene to Cottage Grove.

The completion of a second reservoir increases JWC treated water storage capacity on Fern Hill to 40 million gallons. Increasing stored water capacity is especially important for regional emergency and disaster preparedness. Beaverton Mayor Rob Drake, also a JWC Commissioner, commented in his keynote address that the first reservoir’s construction became especially imperative after Mt. St. Helens erupted in 1980 and ash-filled water kept clogging filters at the JWC Water Treatment Plant and almost shut it down.

Three Commissioners were also honored for serving 20 years or more on the JWC. Will Crandall, City of Hillsboro representative since 1981 and Forrest Soth, City of Beaverton representative since 1987, unveiled the Dedication plaque at the ceremony. Although he was unable to attend the Dedication, Carl Heisler, City of Forest Grove representative since the JWC’s inception in 1976, was also honored for his 31 years of service.

The JWC is a 38-year old organization that operates the largest conventional water treatment plant in Oregon and provides drinking water to approximately 400,000 customers in Washington County. Partners include the Cities of Hillsboro, Forest Grove, Beaverton and the Tualatin Valley Water District. The JWC also sells wholesale water to the City of North Plains.