Herring River Restoration Project
The Herring River is the largest estuary on outer Cape Cod. It stretches four miles from its headwater kettle ponds in north Wellfleet to its mouth at Wellfleet Harbor. The river's floodplain encompasses more than 1,100 acres of degraded wetlands occupying a complicated network of five valleys. Each of these valleys is drained by a creek that contributes water to the Herring River before it flows into Wellfleet Harbor and Cape Cod Bay. Today, finding the river and its floodplain is difficult. The Chequessett Neck Road dike, built in 1908, along with smaller dikes and culverts upstream have impeded natural tidal flows. Ditches dug in the early 20th century to channelize the river effectively drained the normally saturated soil. The once expansive and thriving salt marshes have been transformed into almost impenetrable stands of non-native, invasive plants, shrubby thickets, and forests. The old salt marsh peat, deprived of the tides, has decomposed and compressed, effectively sinking the surface of the floodplain. Today, in some places, the elevation of the Herring River floodplain is three feet lower than it was before the Chequessett Neck Road dike was built. When peat rots, it also releases sulfuric acid which can leach into the river and kill fish and other aquatic life. At times, water in the Herring River is as acidic as vinegar. In addition to high acidity, low summertime dissolved oxygen - also caused by the lack of tidal flushing - makes survival tough for aquatic life.
In 2005, Cape Cod National Seashore and the Town of Wellfleet formed the Herring River Technical Committee to evaluate the feasibility of restoring tidal flows to the Herring River. The Technical Committee's work culminated in a Conceptual Restoration Plan that demonstrated restoration is feasible. Inspired by the work and findings of the Technical Committee, Cape Cod National Seashore, the Town of Wellfleet, and the Town of Truro joined with Massachusetts Coastal Zone Management, U.S. Fish and Wildlife Service, the National Oceanographic and Atmospheric Administration, and the Natural Resource Conservation Service to restore tide to the Herring River. Together, these entities have formed the Herring River Restoration Committee to develop an Environmental Impact Statement (EIS) and an Environmental Impact Report (EIR) for restoration of the Herring River.
Tim Smith, Cape Cod National Seashore, 99 Marconi Site Road, Wellfleet MA 02667, or e-mail CACO_Herring_River@nps.gov