New Water Treatment Plant with PFAS Treatment
2025 Engineering Excellence Best of State
Entering Firms: Becher-Hoppe Associates Inc. & Donohue & Associates Inc.
Client: Wausau Water Works
Keeping Wausau Hydrated
Wausau’s aging treatment plant suffered from reliability issues, inadequate filtration, and floodplain vulnerabilities. These critical challenges threatened the health and safety of 40,000 residents and businesses. To ensure long-term safety and adaptability, Wausau elected to construct a new treatment plant on a secure site, protected from flooding and equipped with space for future expansion.
Addressing All Forms of Pollutants
Becher-Hoppe and Donohue & Associates partnered to implement advanced water treatment technologies, replacing lime softening with catalytic filtration for efficient manganese removal and integrating an anion exchange system to reduce total organic carbon and improve water clarity. Above-ground clearwells and free chlorine disinfection enhanced quality and compliance with regulatory standards. Hydraulic modeling ensured the system met current and future capacity demands, optimizing performance.
Midway through construction, voluntary testing revealed PFAS contamination in the water supply. PFAS are a “forever chemical”, used in many products and that doesn’t break down, creating massive health concerns. Engineers responded swiftly, piloting granular activated carbon and adapting existing technologies to address these emerging contaminants. A long-term treatment system was added post-construction, demonstrating engineering flexibility and innovation.
Awards judge Josh Pachniak said, “The design team took a forward-thinking approach to construct a new water treatment facility to meet the current and future needs of the city. The new facility provides better water quality while also piloting a filtration system to solve the growing problem of PFAS in the public water supply.”
Partnering For the Win
Despite construction surprises, the team completed the project under budget and on schedule, meeting regulatory deadlines. Sustainability guided the design, preserving tree buffers and enhancing stormwater management. Financially, the team secured a $1.6 million federal grant and low-interest loans, significantly reducing costs.
This project exemplifies sustainable, innovative engineering, delivering clean, reliable water while addressing evolving regulatory and environmental demands.