Newmarket Continues on Path to a Cleaner Estuary

Like many other communities in the Seacoast, Newmarket is faced with an aging and outdated sewage treatment plant. As the health of the Great Bay estuary continues to decline, the town is committed to being part of the solution.

Fortunately, Newmarket – along with Exeter – has decided the best way to move forward is to work with EPA and recently became the first community in the estuary to accept stringent nitrogen limits. By voting to accept its permit, the town has taken a significant first step towards addressing the issue of nitrogen pollution – the primary cause of the decline in eelgrass biomass.

The town is to be commended for taking this action. The current facility exceeds its total suspended solids and biochemical oxygen demand monthly average limits during the winter months. The plant has not had a major upgrade since 1985 making it more costly to maintain. A new and updated facility will result in improved water quality in the Lamprey River and Great Bay.

In order to educate residents on why a new plant is needed, the town’s Conservation Commission held a public forum on the “Health of the Great Bay Estuary.” As Waterkeeper, I had the privilege of facilitating the discussion on the town’s plans for a new treatment plant and why the upgrade must be done now.  There were several presentations on the impacts of pollution on the estuary which have caused dramatic habitat changes including a decrease in fish populations. The fact that not all nitrogen is created equal was also discussed.

Sewage treatment plants are a major source of dissolved inorganic nitrogen (DIN) – the most reactive form of nitrogen. While sewage treatment plants are responsible for thirty-two percent of the total nitrogen load to the estuary, they contribute fifty-two percent of the dissolved inorganic nitrogen. According to the Piscataqua Region Estuaries Partnership (PREP) State of Our Estuaries 2013 report, there has been a 68% average increase for DIN between 1974 and 2011. You can read PREP’s entire 2013 report here.

The Forum’s message was clear – if we want to clean up the estuary we need to address point and non-point sources of pollution as well as improving the habitat to allow key species like eelgrass and oysters to thrive. I urge Newmarket votes to approve the warrant article for a new treatment plant on March 12.

For more information about the Great Bay-Piscataqua Waterkeeper and my work to protect the Great Bay estuary, visit: You can also follow me on Facebook and Twitter.

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