Pearly Pond is a key part of the Franklin Pierce University landscape – one the town, the university and the pond’s association have a vested interest in keeping healthy.
Through the help of several grants from the New Hampshire Department of Environmental Service, there have been several measures put into place to help reduce high phosphorous levels in the pond, something that’s been a concern for years. On Oct. 19, Dr. Catherine Owen Koning, a professor of environmental science at Franklin Pierce University, and project manager for the grant projects, will offer a talk on the steps that have been taken to ensure the health of the waterbody, in a two-part talk offered by the Rindge Conservation Commission.
“So many people enjoy water recreation, and so much wildlife depends upon it,” Koning said. “It’s important to the students, the residents, and the wildlife. We know there’s a problem, and we’re trying to address it.”
Pearly Pond is considered to be high in nutrients – particularly chlorophyll-a and phosphorous – which is problematic because high amounts of nutrients can lead to high algae growth. As the algae decays, it uses up oxygen in the water, leaving less available for the fish and tadpoles and other waterlife. Several species of fish can be found in the pond, including the banded sunfish, which is an endangered species.
The invasive plant, milfoil, has also been identified in the pond.
In 2014, with assistance from a DES grant, Franklin Pierce University, the Pearly Pond Association and the Pearly Pond Management Advisory Committee commissioned a study of the pond to determine the main sources of the high phosphorous levels, and set out an action plan to begin to remedy it.
Koning said the biggest sources were determined to be run-off from parking, from the lake’s geese population, and from the campus wastewater production which was once captured in a nearby wetland and is still entering the waterway.
With assistance from a new grant – about $60,000 from DES – the groups are now putting into place some of the measures identified in the 2014 study.
“Once we figured out the sources, we began to look at the options to figure out what we could do,” Koning said.
A filter was installed at the wetland impacted by the campus’s wastewater production, to help reduce the amount of phosphorous entering the pond. And currently being constructed is a “rain garden” on Kimball Road – a depression that has natural filters such as sand and gravel beneath the surface, with plantings on top. Rainwater will collect in the rain garden, and filter into the pond, creating a watersource for the lake.
Koning said the groups have also hired the services of a border collie trainer from Antrim to help scare away the flocks of geese which have been growing unmanageable, with up to 100 geese using the lake during the migratory season, as well as a large population during the year. Geese still use the lake, but at much more manageable numbers, Koning said.
There have also been smaller projects, such as litter clean-ups around the lake, and educating people surrounding the lake on septic care.
And while some of these measures are still in process or in early days, Koning said the dedicated attention to the problem has resulted in a slow reduction of the phosphorous in the lake.
Koning said the next step will be doing a more in-depth review into runoff into the pond, and identifying the most problematic areas.
Koning will speak on the efforts to reverse the declining health on Pearly Pond in a two-part talk at the Rindge Recreation Center on Oct. 19 from 10 a.m. to 11:30 p.m. Hilary Snook, a senior scientist at the Environmental Protection Agency’s New England Regional Laboratory will talk about cyanobacteria, a form of toxic blue-green algae found in local lakes. The talk is open to the public and free.
Ashley Saari can be reached at 924-7172 ext. 244 or asaari@ledgertranscript.com.