The City of Attleboro Russell F. Tennant Water Treatment Facility is located at 1296 West Street, Attleboro. The facility came online in June of 1995 to service the City in meeting the increasingly stringent regulations of the Massachusetts State Department of Environmental Protection and the Federal EPA.

Water from nearby Orr's Pond is screened and drawn into a pretreatment basin where it is mixed with a coagulant, polyaluminum chloride (PAC). The water with PAC then flows into a series of flocculation basins where fine particles (floc) are formed from suspended and dissolved material brought out of solution. The floc swirls in the flocculation basins and grows in size as smaller particles of floc gather together and form larger particles.

After flocculation, the water flows into several sedimentation basins where, over time, the now heavier floc particles settle to the bottom and are removed as a sludge. The clearer supernatant is directed to the Control Building where it passes through a mixed-media filtration system of activated carbon and sand.

Several water treatment chemicals are then added to the newly filtered water for conditioning and disinfection. To ensure that the chemicals are thoroughly mixed in the water, the water passes slowly through a large contact chamber. From there it flows into a storage clearwell before being pumped into the distribution system. The water at this point is now ready for consumer use.

As a whole, residents and industry in Attleboro withdraw between 3 and 6 million gallons of water each day, depending on the season. The annual water withdrawal amounts from all municipal sources are regulated by the Massachusetts Water Management Act.