PREP Reports & Publications


The City of Portsmouth (City) is located in Rockingham County at the mouth of the Piscataqua River in the seacoast area of New Hampshire. The City of Portsmouth’s sewerage system consists of approximately 115 miles of sewers (excluding the Pease International Tradeport), 19 pumping stations, and a 4.8 million gallon per day (mgd) primary wastewater treatment facility (WWTF) located on Peirce Island. The City has an inter-municipal agreement with the Town of New Castle, an island to the northeast of Portsmouth, to treat their wastewater at the City’s Peirce Island WWTF. Additionally, the City has entered into a long-term Municipal Services Agreement (MSA) with the Pease Development Authority (PDA) to maintain and operate the wastewater collection and treatment facilities at the Pease International Tradeport (Pease), the former Pease Air Force Base, and has other agreements with Rye, New Hampshire on behalf of Adams Mobil Home Park and with a private entity located in Greenland, New Hampshire. The Pease facilities include approximately 15 miles of sewers, one pumping station, and a secondary WWTF. The purpose of this project was to extend the city sewer to the Pleasant Point area which is adjacent to the Back Channel area of the Piscataqua River. Seventeen homes in the area were using septic systems to treat wastewater. Several of these septic systems were failing and several more were near failing and contributing to water quality problems. The project included the installation of a low pressure sewer in the Pleasant Point area connecting to an existing gravity sewer on New Castle Avenue. Homeowners are responsible for tying into the sewer services at the edge of their property line. This project helps implement the NHEP Action Plan WQ-7 related to the elimination of failing septic systems. In addition, this project was identified as an MS4 Permittee Action Item in the Total Maximum Daily Load (TMDL) Study for Bacteria in Little Harbor, New Hampshire. This project was funded in part by a grant from the New Hampshire Estuaries Project, a State Revolving Fund loan, Sewer system revenues and private participation.


Piscataqua Region Estuaries Partnership

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New Hampshire Estuaries Project

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