Mattawa Wastewater Treatment and Collection

Project Overview

The facility is designed to meet advanced effluent standards as the discharge is used for ground water recharge.  Funding for the project included grants and loans from PWTF, CDGB, SRF, CCWF, and RECD. The project also included Small Town Environment Program's (STEP) community labor and volunteers and use of prison labor.

Project work included pre-design report, design, surveying, construction and grant administration services for 55,000 lf sanitary sewer collection system, abandoning septic tanks, and a 0.6 MGD wastewater treatment to serve the town that had been served solely by septic tanks.  The WWTP included pump station, headworks, aerated sludge, sludge handling, UV disinfection, and rapid infiltration.

Client Contact

Gary Crowder, Public Works Manager
(509) 830-0719


Mattawa, WA

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