Wastewater EngineeringAdvanced Wastewater Treatment Facility

Riverhead Sewer District

H2M was retained to design the measures necessary to upgrade the existing Riverhead sewage treatment plant to achieve total nitrogen reduction. H2M designed and oversaw the construction of the $8.75 million project. The project was completed on schedule and below the established overall budget.

The Town received a grant for approximately $7 million from New York State under the Clean Air/Clean Waters Environmental Bond Act of 1996. The SBR process consists of two reactor tanks. Each reactor is 67 feet square with a total depth of 23 feet. Each reactor is equipped with a mechanical mixer located in the center of the tank, five retrievable air diffuser assemblies spaced along the perimeter of the tank, a waste activated sludge pump, and an effluent decanter.

Fine bubble aeration was selected in order to reduce horsepower requirements. Ultraviolet disinfection was constructed to take the place of the chlorine gas system to eliminate the discharge of chlorine compounds to the estuary. A sludge holding and thickening system was designed to handle the waste activated sludge from the SBR process and the waste sludge from the Scavenger Waste Treatment Facility, which is also owned and operated by the Town of Riverhead as a separate district.

Advanced Wastewater Treatment Facility

Nitrogen Removal Facility