Project Overview Hockanum River Originally constructed in the mid 1950s as a primary treatment facility, the Hockanum River WPCF was ex- Water Pollution Control panded in 1970 to provide for secondary treatment. The WPCF was further expanded in 1990 to reduce the Facility Upgrade seasonal discharge of ammonia to the Hockanum River. A smaller upgrade was completed in 2004 to replace the chlorine gas disinfection system with a much safer ultra violet disinfection process. The Hockanum River Manchester Water & Sewer Department WPCF currently treats on average 6.5 million gallons per day (mgd) of sewage, with a peak flow in excess of 125 Spring Street 15 mgd. Manchester, CT 06045-0191 Planning for Future Needs www.townofmanchester.org The Hockanum River WPCF is facing several issues that need to be addressed to meet the needs of the com- munity including: Contractor – Nitrogen Removal The Department of Energy and Environmental Protection (DEEP) established strict annual nitro- gen removal limits for all wastewater facilities in the state in order to improve the quality of Long Island Sound. To achieve these limits, the Hocka- 454 Boston Post Road num River WPCF must upgrade its treatment ca- Waterford, CT 06385 pabilities. www.carlincontracting.com – Phosphorus Removal The DEEP has also been working with the Environ- mental Protection Agency (EPA) to establish local water quality limits for phosphorus discharges from WPCFs to fresh water receiving streams such as the Hockanum. The DEEP informed Manchester that as part of the next renewal of the Town’s wastewater Project Engineer discharge permit, strict phosphorus limits would be included. The Town decided to proactively upgrade the Hockanum River WPCF’s treatment capabilities TM to include phosphorus removal to be able to meet these limits when the permit is renewed. – Aging Equipment and Systems Portions of the existing facility have been in contin- 169 Main Street, 700 Plaza Middlesex uous service for over 40 years and some for nearly Middletown, CT 06457 60 years. Much of the existing equipment is ag- ing and approaching or exceeding their expected www.wright-pierce.com service life. Replacement or modifications to these MANCHESTER, CONNECTICUT systems are required to maintain reliable operation of the facility. The Hockanum River Water Pollution Control Facility Upgrade Benefits of Removing Nitrogen Effluent from the Hockanum River WPCF is discharged “eutrophication” which can impair aquatic life and to the Hockanum River which flows to the Connecti- recreational use of Connecticut’s fresh water resources. cut River and ultimately Long Island Sound, where the Because of this, the DEEP will impose effluent phos- Nitrogen and phosphorus removal to dissolved oxygen standard of 6.0 mg/l is violated each phorus limits on 43 municipal WPCFs throughout the improve water quality flowing to the summer in the bottom waters from New Haven west state, including the Hockanum River WPCF. To comply Connecticut River and Long Island Sound to Greenwich. Nitrogen is the primary pollutant caus- with these limits, the Hockanum River WPCF will be ing the low dissolved oxygen condition, or hypoxia. equipped with one of the first tertiary treatment systems Sustainable design to reduce Nitrogen fuels the growth of algae, which eventually in Connecticut designed to reduce effluent phosphorus negative environmental impacts decays, consuming oxygen in the process. Reduced to the low levels necessary to meet the upcoming per- Energy improvements to reduce mit limits oxygen levels can lead to severe ecological and eco- consumption and operational costs nomic impacts. Because Long Island Sound has an estimated value to the local economy of 5.5 billion Energy Saving dollars per year, it is important to reduce the nitrogen Water Pollution Control Facilities are typically one of natural resources are protected, the Town’s Water to levels in order to protect the marine environment. the highest energy users of any municipally operated and Sewer Department worked closely with the local facilities. As part of the upgrade, the Hockanum River Inland Wetlands and Water Resources Commission To comply with the General Permit for Nitrogen WPCF will be implementing a variety of energy relat- and Conservation Commission as well as the DEEP Discharges, the Hockanum River WPCF will be con- ed improvements which are expected to provide sig- and Army Corps of Engineers to ensure that construc- verted to operate in a state-of-the-art nitrogen removal nificant electrical cost savings. Specific improvements tion and operation of the upgraded facility will pro- process as part of the facility upgrade. Once complet- include new variable frequency drives, new energy tect, preserve and enhance the surrounding natural ed, the upgraded facility will remove approximately efficient aeration blowers and a new computerized habitats. The Town of Manchester has also granted a 1,100 lb/d of nitrogen from the raw wastewater. control system to utilize only the power necessary to conservation easement for nearly 5.2 acres adjacent maintain adequate treatment as conditions at the WPCF to the WPCF site. This easement will protect the nat- Benefits of Removing Phosphorus vary throughout the day. Where feasible, new building ural, scenic, aesthetic, and special character of the Nutrient enrichment (nitrogen and phosphorus) has heating systems will utilize water-source heat pumps to property and conserve the property as a natural habi- been identified as one of the most pressing water qual- scavange heat from the treated wastewater to minimize tat for birds, wildlife, plants and similar ecosystems. ity issues facing the nation by the EPA. Similar to the heating requirements. effect of excess nitrogen in Long Island Sound, excess Project Funding phosphorus in local fresh water rivers and streams Protecting our Rivers and Wetlands The project is being funded through the State’s Clean can contribute to low dissolved oxygen conditions The Hockanum River WPCF is located near the con- Water Fund (CWF). Manchester will receive a grant and other water quality concerns. Excess phosphorus fluence of the Hop Brook and Hockanum River. The of approximately 10.65 million dollars to complete from wastewater discharges and runoff from urban and WPCF is also located adjacent to wetlands and near the the project. The remaining costs of approximately agricultural lands can lead to algal blooms or Laurel Marsh and Verplank trails. To ensure that these 40.7 million dollars will be financed through a low interest CWF loan. .