PORTSMOUTH – The City of Portsmouth has submitted its draft Wastewater Master Plan (WMP) to the U.S. Environmental Protection Agency (EPA) and the NH Department of Environmental Services (NHDES) as required by a consent decree with the federal agency, City Manager John Bohenko announced Monday.

            Bohenko said copies of the three-volume draft Master Plan are available at the Library and the City Clerk’s Office at City Hall. The bulk of the voluminous document is posted on the “Wastewater Master Plan Project” , with the remainder expected Wednesday.

            “Over the past 10 years, the City has invested over $25 million in upgrades to our sewage and stormwater system. This draft Master Plan is the result of three years of planning and work,” he said. “The draft outlines the City’s continuing effort and commitment to improving sewage/stormwater treatment on scientific research and the most recent technological advances. It is the City’s goal to deliver environmental benefits while fulfilling our fiduciary duty to Portsmouth taxpayers.”

            The preferred alternative is to expand the Pease Wastewater Treatment Plan in phases and convert the Peirce Island plant to a “wet weather” facility to deal with excess stormwater. Phasing will allow the City to develop additional information to ensure the facility is the correct size and to take advantage of emerging technology. The plan includes the option of upgrading the Peirce Island plant if regulatory issues make the Pease expansion infeasible or overly costly.

              Following feedback from EPA and DES, the City will submit a final version for review by those agencies by September 1. It would not become final until the City Council accepts it.

             The document also expresses concern about NHDES assumptions about the relationship between nutrient levels and the health of the Great Bay estuary, saying they are unsupported by reliable scientific data and could have a multimillion-dollar impact on Portsmouth ratepayers without achieving the goal of preserving the vital water resource. The City believes that before this level of resources is expended, ratepayers are entitled to a reasonable assurance that the investment is necessary and will produce environmental and social benefits.

            Portsmouth recently joined Dover, Durham, Exeter, Newmarket and Rochester in requesting that NHDES initiate a formal rulemaking proceeding that includes an open and independent peer review of its approach in developing Nutrient Water Quality Standards for the Great Bay Estuary, saying new information indicates significant flaws. The EPA’s own Scientific Advisory Board recently criticized a similar approach on the national level. The communities contend that if DES assumptions are indeed incorrect, municipalities around Great Bay could be forced to spend hundreds of millions of dollars on wastewater treatment upgrades without having a significant impact because, as EPA and DES agree, roughly  70% of the estuary’s nitrogen load comes from other sources such as lawn and agricultural runoff, and septic systems.

            DES has acknowledged that less than 10% of Portsmouth’s Peirce Island Wastewater Treatment Plant effluent reaches the Great Bay, but the State and EPA want the City to invest almost $100 million in wastewater treatment improvements that could add $1,200 annually to the average Portsmouth water/sewer bill.

            “The State essentially wants us to make a multimillion-dollar investment retrofitting the Peirce Island plant or expanding the one at the Pease Tradeport, which will dramatically increase our carbon footprint by requiring more energy and chemicals, and impose a heavy financial burden on our ratepayers without adequate assurance that the approach has a sound scientific basis,” Bohenko said. “We have a duty to our citizens to take the necessary time to ensure that when we move forward, it is a science-based solution that truly protects and preserves their health and wellbeing as well as the water quality of the Great Bay. Even by phasing in the upgrades, this will be an extremely expensive undertaking.”

            The Peirce Island Plant, built in 1964 and upgraded in 1991 and 2002, treats 4.8 million gallons of sewage and stormwater daily. Due to changing regulatory standards, the EPA in 2007 declined to reissue a waiver allowing primary treatment and ordered the City to add secondary treatment, which involves using biological agents to remove dissolved organic matter before the wastewater leaves the plant. Secondary treatment requires a larger facility and more equipment at a cost as high as $100 million, with operating costs increasing by an additional $1.5 million annually.