Lake Oswego Water Treatment Plant

Facility Description

The City of Lake Oswego has operated a drinking water treatment plant in West Linn’s Robinwood neighborhood since 1968. The Lake Oswego Tigard Water Partnership plans to upgrade and expand the treatment plant, located between Kenthorpe Way and Mapleton Drive, to meet current and future drinking water needs. The upgraded plant will supply Lake Oswego and Tigard, and will continue to serve as West Linn’s sole source of emergency and backup water supply.

History of the Water Treatment Plant

Built in 1968, Lake Oswego’s water treatment plant was originally located in unincorporated Clackamas County. The area was later annexed by West Linn. Through its 44-year history the plant has earned a reputation as a good neighbor. The City of West Linn has approved land use applications for upgrades and expansions three times since the plant was built.

It is not uncommon for wastewater and water treatment plants to be located in residential areas. South Fork Water Board’s treatment plant – jointly owned by West Linn and Oregon City – is located in Oregon City’s Park Place neighborhood. Extensive upgrading, expansion and treatment modifications have occurred there over the past several years to serve the two communities.

Water Treatment Plant – Good Neighbor Plan

Lake Oswego Tigard Water Partnership began discussions with the Robinwood Neighborhood Association in early 2010, sharing details of the water treatment plant expansion, listening to suggestions, and finding ways for the upgraded water plant to continue to be a good neighbor. Two years later, the Partnership has met with Robinwood neighbors more than 20 times, developing a Good Neighbor Plan (pdf, 308 kb) that contains the Partnership’s commitments for design–construction–operations of the new facility. Neighborhood input played a big role in design concepts with the addition of numerous plant layout changes and amenities requested by neighbors.


How to Get Involved

  • Click here for upcoming meeting dates.
  • Sign up to receive email notices.  Mark the ‘Water Treatment Plant' as your interest.
  • Click here to contact us by email.
  • Call the Water Hotline (503) 697-6502.

Additional Information

You can find regular updates on the Work Underway page.

Field Updates

Thursday - March 5, 2015

Permanent trench patching to begin on Highway 43

Dump-trucks delivering gravel to refill the pipe trench on Highway 43.

West Linn Pipeline Construction Update

This update includes construction work in the following areas. Read More for specific information on each location:

  • Highway 43 – Major pipe installation almost complete; permanent trench patching to begin next week!
  • Open for Business - Check out the multi-page color insert in the West Linn Tidings next week and support local businesses along Highway 43
  • Mapleton Drive - Exploratory digging begins next week; tree trimming in March

Read More

Friday - February 20, 2015

Construction moving steadily along in West Linn

West Linn Pipeline Construction Update

This update includes construction work in the following areas. Read more for specific information on each location:

  • Highway 43 – Crews moving steadily along near Shady Hollow Way
  • Mapleton Drive – Exploratory digging to begin in March
  • Open for business – Businesses along Highway 43 remain open during construction

Read More

Thursday - February 12, 2015

New chemical tanks installed at the WTP this week

Chemical tanks

Clearwell is almost complete

Work occurring on the new structures and across the site includes:

Chemical and electrical buildings - center of site

Crews finished applying the protective coatings on the interior of the chemical building and, this week, installed six large chemical tanks within the structure (pictured right). Work will now begin to install chemical piping systems and electrical connections.

For the electrical building, crews have installed the lower level of the HVAC system and electricians are working inside the structure. Over the next few weeks, crews will begin placing the brick veneer, siding panels, and roof panels.

Read More