• Atlantic Ocean beach at Cape Cod National Seashore

    Cape Cod

    National Seashore Massachusetts

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  • Access at seashore locations

    The stairs at Nauset Light Beach in Eastham are closed due to storm damage. Herring Cove North Lot in Provincetown sustained damage resulting in closure of multiple parking spaces. The Nauset Marsh Trail bridge was destroyed in a 2012 storm. More »

Water Quality

Water quality data collection

Two Student Conservation Association interns collect water quality data at Spectacle Pond in Wellfleet.

Photo by Naomi Blinick

Natural resources in National Park Service units are facing unprecedented challenges. Water quality of aquatic ecosystems within Cape Cod National Seashore are threatened by the combined effects of climate change, adjacent development, mercury deposition, acid rain, oil spills, and visitation by the public. An increasing proportion of the 5 million annual visitors to the park use the salt and fresh-water resources for swimming, fishing, boating and other recreational activities, and there are many private homes with individual septic systems that contribute nutrients to the adjacent waters.

In freshwater kettle ponds, increased nutrient inputs can lead to algal blooms, low oxygen in the water, and changes in thermal layer formation. In brackish and salt waters, nutrient enrichment leads to a cascade of events, including algal blooms, low oxygen conditions, loss of seagrass meadows, and fewer invertebrates and fish. Changes in climate, as well as mercury and other particles deposited from the atmosphere through wind and rain, contribute to declining water quality across the region. Monitoring water quality of aquatic resources aids in developing management strategies for protection and mitigation by identifying the source and level of impacts to a given ecosystem.

Did You Know?

Wellfleet kettle ponds

There are twenty permanently flooded freshwater kettle ponds within the Cape Cod National Seashore. They range in size from 2.5 to 100 acres and from 6 to 65 feet in depth.