Wilsonville Wastewater Treatment Plant Project
Clean Water for Tomorrow   

Expert Team will Build and Operate the Plant

Wilsonville is using a Design-Build-Operate (DBO) method of contracting. DBO involves hiring a large firm with the broad based knowledge of and expertise to both operate, and design and build large wastewater facilities. There are very few firms in the country that have these capabilities.

CH2M Hill is Wilsonville's selected DBO contractor. They will be responsible for operating the plant for a minimum of 15 years, meeting set performance measures. The company will design and construct the plant with this long term commitment in mind thereby minimizing life cycle costs. Another important component of DBO is that a single firm will be responsible for both plant  operations and the improvements so any problems or disruptions in service during construction are handled by a single entity.

The City of Wilsonville will continue to own the treatment plant and the community’s other wastewater facilities. The DBO company will operate and maintain the upgraded treatment plant, along with eight pump stations. Wilsonville Public Works staff will continue to maintain the sewage collection system.

The DBO contract has very distinct criteria, and contract values, for each aspect of the work. The Design-Build portion of the contract sets a fixed price of $35, 707,414 for the D-B work and a 911 day performance period. The operations part of the contract sets a first year value of $1,395,605, allows annual escalation, and sets a 15-year term.

Click on the following series of articles for an overview of the Wastewater Treatment Plant and individual unit processes.

Improving the WWTP

Liquid Treatment Process


Odor Control

Biosolids Processing

Filtration and Disinfection

Fact Sheet

Project Performance Report August 2013