Restoring Great Bay Estuary: Massive Oyster Reef Construction in the Lamprey River, Great Bay Largest Project of its Size in Region

The Nature Conservancy's New Hampshire Chapter, together with the University of New Hampshire and other partners are stepping up efforts to restore a key waterway in a very big way.

Newmarket, NH | June 20, 2011

The Nature Conservancy’s New Hampshire Chapter (TNC), together with the University of New Hampshire (UNH) and other partners are stepping up efforts to restore a key waterway in a very big way. From June 21st through June 24th, TNC and UNH scientists will be working with a local marine contractor, Riverside & Pickering of Eliot Maine, to construct 2.5 acres of oyster reef at the mouth of the Lamprey River in Great Bay.  The barge crew will be placing 225 tons of clean, recycled surf clam shell on the river channel bottom in carefully arranged plots that form a living reef.  The thin layer of shell acts as the foundation for oyster spawn to set on naturally, and it provides a base for thousands of disease-resistant juvenile oysters raised at a UNH hatchery by Dr. Ray Grizzle.  This is the largest ever project of its kind north of Cape Cod.

“Vast reefs of live oysters once covered the bottom of the Great Bay Estuary, filtering out excess nutrients, providing habitat to a diversity of fish, and offering recreational harvest to generations of locals,” said Daryl Burtnett, TNC Director. “But due to pollution, disease and over-harvest, we have lost 90% of our reefs. Using surf-clam shell from offshore draggers, locally recycled oyster shells, hatchery set oysters and volunteer-raised juveniles, we are rebuilding the oyster reefs of Great Bay acre by acre.“

In all, 100,000 square feet of shell reef will be rebuilt in an area once teeming with oysters but now covered only with silted bottom and scattered shells.  Once the annual spawn is over and the hatchery work is complete in the fall, about 500,000 new oysters are expected to reside on these new reefs.  And the reefs are in areas closed to harvest so they can act as spawner sanctuaries for the rest of the estuary.

“Oysters may be Great Bay’s best hope for sustainable recovery of our estuary.” said Dr. Ray Konisky, Director of Marine Science for TNC.  “These resilient animals are amazing at water filtration, and right now we have a major problem with excess nutrients.  Towns are grappling with meeting the necessity to remove more nutrients from their wastewater. We want to complement those efforts by re-establishing healthy oyster reefs.  So we’re rebuilding oyster reefs as a way to help nature bring the estuary back into balance.”

TNC and UNH have formed a partnership to restore oyster reefs.  Construction techniques with surf clam shell were started with a pilot study in 2009, expanded to a more than an acre in 2010 in the Oyster River (Durham), and doubled again in 2011 with the work at the Lamprey River site.

In addition to reef construction, community volunteers are a big part of the oyster restoration success.  Now in its sixth season, the NH Oyster Conservationist Program engages about 25 homeowners around the Bay who raise juvenile oysters on their docks for the restoration reefs.  In addition, the UNH Docents provide labor for some of the shell handling duties.  And the Coastal Conservation Association (CCA) operates a NH and ME oyster shell recycling program for restaurants that recovers about five tons of shell per year for hatchery operations.  Community support is an integral part of the restoration program.

Funding for oyster restoration comes from a variety of federal, state, and private sources.   Lead funders include the Piscataqua Region Estuaries Partnership, NOAA Restoration Center, Natural Resources Conservation Service, State of NH Conservation License Plate Program, The Davis Conservation Foundation, and many private donors.

For more information about reef construction and the Oyster Conservationist Program, visit  For information about the restaurant shell recycling program, go to  For marine contracting services, call Lori at Riverside & Pickering 603 502-0578.


The Nature Conservancy is a leading conservation organization working around the world to protect ecologically important lands and waters for nature and people.  To date, the Conservancy and its more than one million members have been responsible for the protection of more than 18 million acres in the United States and have helped preserve more than 117 million acres in Latin America, the Caribbean, Asia and the Pacific. The Nature Conservancy in New Hampshire has helped protect more than 270,000 acres of critical natural lands.  Visit The Nature Conservancy on the Web at

The Nature Conservancy is a global conservation organization dedicated to conserving the lands and waters on which all life depends. Guided by science, we create innovative, on-the-ground solutions to our world's toughest challenges so that nature and people can thrive together. We are tackling climate change, conserving lands, waters and oceans at unprecedented scale, and helping make cities more sustainable. Working in more than 65 countries, we use a collaborative approach that engages local communities, governments, the private sector, and other partners. To learn more, visit or follow @nature_press on Twitter.

Contact information

Dr. Ray Konisky
Director of Marine Science & Conservation
The Nature Conservancy in New Hampshire's Great Bay Office
112 Bay Road
Newmarket, NH 03857
603.659.2678, x 13

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