Blackwater River by Rt. 286, Seabrook

About this Location

The Blackwater River is a 3.1-mile-long tidal inlet in northeastern Massachusetts and southeastern New Hampshire.

The river forms in a salt marsh in the northeastern corner of Salisbury, Massachusetts, by the convergence of the Little River and Dead Creek. Heading north, the river quickly enters Seabrook, New Hampshire and continues to flow through salt marsh until it reaches Hampton Harbor, northwest of Seabrook Beach, where it joins the Hampton River.

About Hampton-Seabrook Marsh

See all hotspots at Hampton-Seabrook Marsh

At 5,000 acres, the Hampton-Seabrook Estuary contains the largest amount of salt marsh in the state. These marshes, along with their associated tidal flats, provide critical habitat for breeding and migratory birds, particularly shorebirds and salt marsh sparrows. Between 2006 and 2007, NH Audubon undertook a comprehensive avian assessment of this estuary, with the goal of obtaining information on the distribution of breeding birds and seasonal patterns of use by migrating shorebirds. The results were published in “Avian Use of the Hampton-Seabrook Estuary” and documented the estuary’s importance to these two groups of birds.

Following this study, New Hampshire Audubon also produced a brochure that summarized the findings of this study and presented conservation priorities for the estuary. This brochure has been made available to stakeholder groups in the region, including Conservation Commissions, recreation facilities, and interested individuals.

Moving forward, the conservation of salt marsh birds is a clear priority in light of potential sea level rise induced by climate change. New Hampshire Audubon is working with partners at the University of New Hampshire and the University of Maine to conduct surveys for sparrows and other breeding birds as part of a larger regional project. Data from our 2006-07 project will shortly be incorporated into a scientific paper on the effects of salt marsh ditching.


  • Roadside viewing

  • Restrooms on site

  • Wheelchair accessible trail

  • Entrance fee

Content from Hampton-Seabrook Marsh (New Hampshire Audubon) webpage and Wikipedia

Last updated October 23, 2023