ATLAS Technical Commentary

From a B2B industrial water treatment engineering and utility asset management perspective, the City of Dayton’s selection of Tetra Tech for this $350 million, 8-year design contract represents a defining capital milestone following the US EPA’s National Primary Drinking Water Regulations (NPDWR). Enforcing legally binding 4 ppt limits for PFOA and PFOS makes conventional surface water treatment trains obsolete for contaminated source-waters.

The engineering scope directly addresses legacy contamination within the Mad River Well Field, which supplies the 70-year-old Ottawa Water Treatment Plant (generating 96 MGD of potable water for over 430,000 regional residents). Addressing PFAS at this hydraulic scale requires large-footprint adsorption and exchange technology: integrating high-volume Granular Activated Carbon (GAC) adsorber vessels and high-selectivity Anion Exchange (AIX) resin skids arranged in Lead-Lag vessel arrays. Crucially, the engineering design focuses on optimizing front-end hydraulic pressure distribution, automating media changeout workflows, and incorporating real-time breakthrough sensors to minimize lifecycle O&M expenditure and lower overall Cost of Water.

News Summary

GLOBAL MARKET MONITOR (July 21, 2026) — Leading global consulting and engineering firm Tetra Tech, Inc. (NASDAQ: TTEK) announced today that the City of Dayton, Ohio, Department of Water, has selected the company for a single-award contract to design advanced treatment solutions for what will be the largest dedicated per- and polyfluoroalkyl substances (PFAS) treatment facility in the United States, with a projected construction cost of $350 million.

Under this eight-year contract, Tetra Tech will build on prior planning work to execute comprehensive engineering solutions addressing legacy regional PFAS contamination in the Mad River Well Field. This vital groundwater source supplies the City’s 70-year-old Ottawa Water Treatment Plant, which generates 96 million gallons per day (MGD) of potable drinking water for more than 430,000 people across the region. Tetra Tech’s scope includes process design, pilot testing, hydraulic modeling, and construction support, deploying high-efficiency Granular Activated Carbon (GAC) and Ion Exchange (IX) resin architectures to satisfy strict US EPA regulations while minimizing long-term lifecycle operating costs.

Media & Source Attributions: Tracked via Tetra Tech Official Investor Relations.