Where Does My Water Come From?

Water Source

The highly protected and pristine Clackamas River is the drinking water source for the Lake Oswego Tigard Water Partnership. This high-quality water source receives runoff and snowmelt from a 940 square mile area located on the western slopes of Ollalie Butte, near Timothy Lake, in the Mount Hood National Forest.

Over, Under, Around and Through: A Journey from the River to your Tap

Water is withdrawn from an intake facility on the Clackamas River in Gladstone. It is then pumped through a large-diameter pipeline through the City of Gladstone to Meldrum Bar Park. From here, the water travels through a pipeline that is buried under the Willamette River bed and onto the water treatment plant in West Linn. Here, water is treated to exceed safe drinking water standards. Treated water is then pumped through another large-diameter pipeline to the Waluga Reservoir site in Lake Oswego. From here, water flows through Lake Oswego’s distribution system, comprised of 16 storage reservoirs, 13 pump stations and about 210 miles of pipes to serve Lake Oswego customers. From the Waluga site, water also flows to the Bonita Pump Station in Tigard and through the City of Tigard’s distribution system, comprised of 14 storage reservoirs, 6 pump stations and about 250 miles of pipes that serve Tigard Water Service Area customers.

Clackamas River Development

Since 1968, Lake Oswego’s drinking water source has been the Clackamas River. In the early 1970’s, Lake Oswego began supplying water to Tigard under a surplus water agreement, but as Lake Oswego’s demands grew, the availability of surplus water decreased and Tigard began purchasing water from Portland. With the Partnership’s newly expanded water supply system, Tigard ended its supply agreement with Portland in 2016 and receives its water from the Clackamas River.

Protecting the River

The Clackamas River is one of Oregon’s highest-quality drinking water sources and is afforded special protection under state law. The Clackamas River watershed provides drinking water for more than 400,000 Oregonians in several communities in North Clackamas County.

Service Area

The Partnership supplies water to more than 100,000 customers within the Lake Oswego and Tigard Water Service Area, including the cities of Durham and King City, and two-thirds of Tigard. The City of Lake Oswego also supplies water to wholesale customers including the City of Portland, and the Lake Grove, Glenmorrie, and Skylands Water Districts.