The City of Lake Oswego in the USA received four submissions of the statement of qualifications in response to the request for a qualification issued earlier this year to upgrade or replace Tryon Creek Wastewater Treatment Plant.

A committee organized by the City of Lake Oswego will review the statements of qualification over the next month. It is hoping to initiate a request for proposals in June.

In 2018, the City Council has received a proposal from PERC Corporation to replace the old wastewater plant that has been in operation for 55 years with a new type of wastewater technology known as a membrane bioreactor (MBR) that can potentially reduce the plant's carbon footprint from 13.5 acres to 3.5 acres. The proposal has been used to start the further exploration of the project. 

The Tryon Creek Wastewater Treatment Plant is located in Lake Oswego, but is owned by the City of Portland and treats water from both municipalities. Any decision on repair or replacement of the plant will require amending the intergovernmental agreement between two cities.

The 2014 study financed by the two cities found that the replacement of the plant would cost less than upgrading of the existing plant. The cost of the replacement was quoted as US$112 million and the upgrade - US$154 million.