PRB Installed to Reduce Nitrogen Entering the Sagg Pond Watershed

October 5, 2023

By Julia G. King

Conservation News
Water Quality

The Sagg Pond Watershed is suffering from the effects of excessive nitrogen and other nutrients leading to harmful algal blooms. This causes poor water quality and dead zones in the pond making it unsafe for those wanting to recreate in the pond. Marine life is also threatened.

However, good news is on the horizon. The Peconic Land Trust working with our partners at the Cornell Cooperative Extension’s Marine Center have been researching the locations of nitrogen-rich groundwater seepage into the pond and potential remediation methods to remove nitrogen before it reaches the pond.

This Fall we installed the first permeable reactive barrier (PRB) in the watershed. PRBs are a remediation method that breaks down nitrogen and other nutrients before they reach the pond using natural materials such as wood chips. We plan to install at least two more PRBs in the next 12-18 months in key areas around the pond.

PRB column installation at a property on the east side of Sagg Pond. PRB columns were composed of a mixture of locally sourced materials (woodchips and pea gravel) which was deposited 30 ft below ground. The mixture was funneled into a hollow stem auger to create the column.


Schematic from Cornell Cooperative Extension of a PRB at the edge of a farm field adjacent to an impaired waterbody.

PRBs were chosen because they don’t require extensive maintenance and have the potential to remain effective for decades. PRBs have been used extensively in the Midwest to treat agricultural tile drainage runoff. In nearby Hampton Bays, a PRB installed by CCE behind a bulkhead has successfully reduced nitrogen levels in the mixing zone between groundwater and the sea.

This critical research and remediation work is only possible because of the passion and generosity of the Sagg Pond community. We’re so grateful for your support!

To learn more about the Trust’s work in the Sagg Pond Watershed, contact Matt Swain, Vice President.

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