what we do


Engineering innovative wastewater treatment solutions

Increasing population, aging infrastructure, and stricter regulations have put pressure on wastewater conveyance and treatment systems. Parametrix develops sustainable, cost-effective solutions. In addition to traditional approaches, we are experienced in designing systems for advanced membrane filtration, reclaimed water, enhanced nutrient systems, and biosolids management. From collection and conveyance to treatment and reuse, we are exploring new ways for our clients to improve their operations and meet today’s challenges.

LOTT Biological Process Improvements
LOTT Biological Process Improvements
Olympia, Washington
Client: LOTT Clean Water Alliance

LOTT provides wastewater treatment and water reclamation services and operates the Budd Inlet Treatment Plant. The Washington State Department of Ecology has initiated a general permit process that will eventually require all 84 wastewater treatment plants discharging into the Puget Sound to implement biological nutrient removal (BNR). BNR is an important treatment process to reduce nitrogen in wastewater effluent. This process reduces nutrient loading in receiving water bodies, which can cause harmful algal blooms and low oxygen levels in the marine ecosystem. While LOTT has been performing nutrient removal since 1994, they partnered with Parametrix to design this new “second generation” BNR upgrade and associated process improvements at the Budd Inlet Treatment Plant.

The project converted the first aeration basin into a BNR basin and also replaced aging equipment, like over-sized blowers, and increased process reliability by enhancing operational flexibility with new instrumentation and controls equipment. Innovative treatment processes are being implemented to increase efficiency and provide plant operational flexibility, including using new large-bubble mixing technology that is the first of its kind on the West Coast. The new technology uses only 10 percent of the power of the mixing system it replaced. The improvements are being constructed in three stages, during which, the treatment plant must remain operational and continuously meet permit limits. When complete, the world class upgrades will improve treatment process reliability, significantly reduce energy usage, and contribute to overall system capacity.

Learn more about the project on our Inspired People Blog




"...excellent project management throughout the project to keep the project on schedule and within budget... Your staff did an outstanding job of designing the facilities and managing the construction."

Steven Schuller, PE, former City of Duvall Director of Public Works