Water Treatment Plant History

People have lived in the Rogue River watershed for at least 8,500 years. The river provides world-famous white-water recreation, parks, hiking trails, and campgrounds. 

Water from the Rogue River has supplied the City of Grants Pass with its drinking water since 1888. A company called the Grants Pass Water, Light and Power Company was formed in 1893 for the purpose of operating a powerhouse on the river and eventually supplying the city with water, gas, and electricity.

Between 1888 and 1889, a dam was constructed across the river a half-mile west of 6th Street to divert the water from the south bank to a powerhouse located on the north bank. In 1900 and 1901 extensive work was done to improve the dam; however, it would still wash out and need to be rebuilt.

Early 20th Century

In 1906, the Rogue River Water Company purchased the water system.  At that time water was pumped directly from the River and treated with chlorine.  At certain times of the year the water was cloudy. At these times it needed to be filtered to make it clear and pleasant tasting.  The powerhouse was operated until July of 1907 when a new pump station was installed 3,000 feet upstream from the 6th Street Bridge.  Overtime, as the town grew, there was also a need for water storage. 

In 1931 the City of Grants Pass purchased and began operating the water system.  They also began construction of the current Water Treatment Plant and a reservoir.  

Mid Century

The people of Grants Pass have always valued its water resource.  In the early 1950’s, to keep up with growth in the community and needs for larger quantities of safe, clean drinking water, the Water Treatment Plant was significantly expanded.  It then expanded again in 1962 and 1983.Today it can produce 20 million gallons of treated water per day compared to its initial capacity of 2.25 million gallons.  The reservoir capacity increased from its original 600,000 gallons to its present 19.2 million gallons of water.

New Century

Today, water from the treatment plant is pumped by 13 remote booster-pumping stations and stored in -8 reservoirs located throughout the City. This distribution system is made up of five distinct pressure zones that change as elevation increases and covers the entire City, Urban Growth Boundary, and areas around the Merlin landfill and North Valley industrial complex.

Liquid chlorine is added at strategic points in the distribution system to maintain the chlorine residual that is mandated by the Oregon Health Authority - Drinking Water Program and Federal Guidelines. This chlorine residual is to ensure that bacterial growth cannot occur in the distribution system and that your water remains safe for domestic use and consumption.  Extremely high- water quality is ensured through continuous monitoring and by bacterial, chemical, and radiological tests taken daily from numerous sites throughout the distribution system.

Challenges and Solutions

The Water Treatment Plant is now among the oldest original water facilities in the State of Oregon.  The plant is well past its designed life cycle and is becoming increasingly difficult and expensive to maintain.  Discussions about replacing the plant began as early as 2004 in a report titled the Water Treatment Plant Facility Plan (WTPFP) for the City of Grants Pass (City).  The 2004 WTPFP outlined an approach for improving the City’s water treatment plant (WTP) and recommended a two-tiered capital improvement program (CIP).  Grants Pass successfully implemented several improvements; however, conditions at the WTP continued to deteriorate. More formal discussions about replacement began in 2013-14 when an update to the WTPFP was being prepared. The update considered a variety of scenarios ranging from continued repairs to replacement and included an initial assessment regarding potential areas to relocate the plant.

WTP Timeline