UOSA Regional WRP Upgrade and Improvement Projects

Numerous improvement projects on facilities approaching their end of life.

Treatment Plant Facilities
Centreville, VA
Delivery Method
Design-Bid-Build / Design-Build
Upper Occoquan Service Authority
Year Complete

Project Overview

PC completed seven projects totaling $54 million during a three-year period to address aging facilities and processes at the Upper Occoquan Service Authority Regional Water Reclamation Plant.

The primary clarifiers, odor control process, and hydraulic system was upgraded, as was the nutrient compliance facilities. A new multiple hearth carbon regeneration furnace with ancillary systems was incorporated to produce 12,000 pounds of reactivated carbon per day, and a new cogeneration unit with two 350-kW generators and 600-hp blowers increased aeration efficiency and provided energy savings.

Improvements to the solids treatment process included the installation of a new gas-fired rotary drum system and replacement of three dewatering recessed chamber filter presses. In addition, the standby power system was upgraded to replace existing medium-power switchgear, remove and replace diesel storage tanks and upgrade three standby generators.


Total Contract Value Over Seven Contracts


Contracts Self-Performed by PC


MGD Water Reclamation Facility