CHATTANOOGA, TN — The Archer Western-Stantec design-build team has been selected to complete Phase 1 of a Class A Process Optimization for Wastewater Energy Recovery (POWER) project and wastewater treatment plant upgrades for the City of Chattanooga Moccasin Bend Environmental Campus. Archer Western Construction will serve as the lead contractor while Stantec will lead design and engineering.

This progressive design-build project is expected to incorporate a thermal hydrolysis process (THP) facility, anaerobic digestion upgrades, and conversion of a high purity oxygen facility to a membrane aerated biofilm reactor (MABR). Upon completion, the project will be the largest MABR facility in the world. MABR is an energy-efficient, intensified nutrient-removal process that will allow the city to utilize its existing tanks rather than having to build new ones — while meeting future nutrient limits in effluent discharged from the Moccasin Bend Environmental Campus.
To meet the city’s sustainability and operational goals, the biosolids portion of the project will integrate the THP facility within the existing biosolids treatment process, improving anaerobic digestion and biogas production while reducing the volume of biosolids for disposal.

The facility will produce Class A biosolids that can be used as a soil additive for surrounding farms in the region. The biogas will also be reused to generate steam within the Moccasin Bend Environmental Campus, with the excess generating power for the facility.

“It’s a privilege for our team to support the City of Chattanooga, a long-time client, on its largest capital project under a U.S. EPA Consent Decree,” said Harold Schmidt, Wastewater Sector Director for the U.S. South region at Stantec. “Our team’s design will aim to meet the immediate and enduring wastewater infrastructure needs of the city using efficient, cost-effective processes.”

“Archer Western is honored to partner with Stantec and the City of Chattanooga on this transformative project. We look forward to the close collaboration and progressive design-build delivery that will bring innovative, efficient upgrades to the city’s wastewater operations,” said David Walker, Vice President at Archer Western. “Working alongside Stantec, we’re committed to delivering a state-of-the-art project that adheres to the highest standards of safety and quality to meet the city’s goals for energy reduction."

In support of the city’s green initiatives, this project will create a positive community impact with a design that focuses on sustainability and efficiency. The city has committed to a six-goal climate action plan to reduce disparities among socially and economically vulnerable communities, reach net-zero carbon emissions, achieve zero waste, build a more sustainable city, preserve and improve natural resources, and be a leader in the green economy. The project is an important step toward achieving zero carbon emissions by 2050.

Stantec has had a relationship with the City of Chattanooga for the past decade, serving as a resource for on-call services. This project, which began as a pilot, will be the largest project the firm has completed for the city to date.