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

Friday - March 20, 2015

Last piece of pipe installed on Highway 43

Final piece of 48-inch steel pipe installed on Highway 43

Crews cutting the final piece of pipe!

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

  • Highway 43 - Last piece of 48-inch pipe now installed; permanent trench patch more than halfway complete!
  • Open for Business - Support local businesses along Highway 43
  • Mapleton Drive - Exploratory digging almost complete
  • Meet the Mapleton Drive Pipeline Contractor - Meeting to be held soon

Read More

Friday - March 13, 2015

Startup of solids structures underway at the WTP

Pipe installation on the east of the site

Screw presses

Water Treatment Plant Construction Update

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

New administration building – north of site

The contractor expects to begin working on the foundation of the new administration building soon, which will be located next to the existing administration building and in the current parking lot off Kenthorpe Way. Next week, crews will begin removing some of the landscaping on the north side of the existing plant parking lot, laying down gravel and creating a temporary parking lot for the plant staff. Neighbors close to site on Kenthorpe Way may notice an increase in noise or potential vibration during this work.

Read More

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