SALEM, N.H. — A 10-year watershed management plan promises to explain the causes of poor water quality at Captains Pond and design solutions.
The town will present a draft plan to the community during a meeting from 5 to 6 p.m., Tuesday, Aug. 18, at the Town Hall. Although town engineers, with help from consultant Weston & Sampson, drew up a preliminary report in 2021, the updated draft relates to the entire watershed including portions of Atkinson and Haverhill.
“Captains Pond has suffered from chronic water quality issues for many years,” Salem Engineer Director John Klipfel said in a 2024 memo regarding funding the review. “The project will also include efforts to implement some management measures identified in the preliminary watershed-based plan.”
Measures include tree trenches; a green piece of infrastructure that manages stormwater through an underground pipe beneath a row of trees.
The plan is being funded through a $100,000 loan from the federal Clean Water State Revolving Fund, which provides low cost financing for projects that improve water quality, according to a presentation by the consultant.
A watershed is the area of land where runoff, sometimes containing harmful pollutants, flows into a local water body. Planners have been looking for strategies to reduce contaminants, either through physical structural controls or changes in practices.
The pond’s shoreline has been the setting of multiple summer camps and is also surrounded by nearby roads.
Members of all three communities and any interested parties are invited to attend. Planners intend to incorporate feedback into the final plan.
In 2022, cyanobacteria blooms forced officials to close the pond to swimmers and boaters. There are no active cyanobacteria advisories at the pond as of Wednesday afternoon, according to a state map.
Cyanobacteria are microscopic organisms naturally found in lakes, rivers and oceans. However, in the presence of excessive nutrients in the water, like nitrogen and phosphorus, they can grow to unsafe levels.
The blooms can lead to oxygen degradation and are in some cases toxic. Exposure can result in hay fever-like symptoms, skin rashes and respiratory, and gastrointestinal distress, according to the Center for Disease Control(CDC).
Cyanobacteria was cited in a 2019 state report on the pond. Scientists also use other metrics to compare water quality, including phosphorus, a nutrient fed upon by the bacteria.
“Pond phosphorus levels were the highest measured since monitoring began and have fluctuated within a higher range since 2017,” the state said in a 2024 water quality report. “Lab data note moderate levels of organic matter in the sample suggesting a layer of algal or Cyanobacteria growth at that depth.”
Elevated levels of E. Coli have also been reported in the pond at points in the last few years.
For information by the state on active cyanobacteria blooms visit: tinyurl.com/42yrb4u6