The Powwow River is a 22.8 miles (36.7 km) river

River

A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...

 located in New Hampshire

New Hampshire

New Hampshire is a state in the New England region of the northeastern United States of America. The state was named after the southern English county of Hampshire. It is bordered by Massachusetts to the south, Vermont to the west, Maine and the Atlantic Ocean to the east, and the Canadian...

 and Massachusetts

Massachusetts

The Commonwealth of Massachusetts is a state in the New England region of the northeastern United States of America. It is bordered by Rhode Island and Connecticut to the south, New York to the west, and Vermont and New Hampshire to the north; at its east lies the Atlantic Ocean. As of the 2010...

 in the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

. It is a tributary

Tributary

A tributary or affluent is a stream or river that flows into a main stem river or a lake. A tributary does not flow directly into a sea or ocean...

 of the Merrimack River

Merrimack River

The Merrimack River is a river in the northeastern United States. It rises at the confluence of the Pemigewasset and Winnipesaukee rivers in Franklin, New Hampshire, flows southward into Massachusetts, and then flows northeast until it empties into the Atlantic Ocean at Newburyport...

, part of the Gulf of Maine

Gulf of Maine

The Gulf of Maine is a large gulf of the Atlantic Ocean on the east coast of North America.It is delineated by Cape Cod at the eastern tip of Massachusetts in the southwest and Cape Sable at the southern tip of Nova Scotia in the northeast. It includes the entire coastlines of the U.S...

 watershed

Drainage basin

A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...

.

River course

According to USGS topographic maps, the Powwow River rises in the center of Danville, New Hampshire

Danville, New Hampshire

Danville is a town in Rockingham County, New Hampshire, United States. The population was 4,387 at the 2010 census. Danville is part of the Timberlane Regional School District, with students attending Danville Elementary School, Timberlane Regional Middle School, and Timberlane Regional High...

, and flows southeasterly through Long Pond into Kingston

Kingston, New Hampshire

Kingston is a town in Rockingham County, New Hampshire, United States. The population at the 2010 census was 6,025.- History :Kingston was the fifth town to be established in New Hampshire. Originally, it was a part of Hampton, New Hampshire...

, where it enters Great Pond

Great Pond (New Hampshire)

Great Pond is a water body located in Rockingham County in southeastern New Hampshire in the United States. The lake lies near the center of the town of Kingston. Kingston State Park, a small preserve with a swimming beach, occupies the northeastern end of the lake, near the town center. The...

, a 268 acres (108.5 ha) water body in the center of the town. Leaving Great Pond, the river enters an extensive network of wetlands and receives a major tributary from the southwest, the outlet of Country Pond

Country Pond

Country Pond is a water body located in Rockingham County in southern New Hampshire, United States, in the towns of Kingston and Newton. Water from Country Pond flows via the Powwow River to the Merrimack River in Amesbury, Massachusetts....

, situated in Kingston and Newton

Newton, New Hampshire

Newton is a town in Rockingham County, New Hampshire, United States. The population was 4,603 at the 2010 census.- History :The sixth town to be granted from the Masonian land purchase of 1746, Newton was originally part of Salisbury, Massachusetts; later, part of Amesbury, Massachusetts; then...

. Continuing east, the Powwow River enters Powwow Pond

Powwow Pond

Powwow Pond is a water body in Rockingham County in southeastern New Hampshire, United States. The outlet of the pond is located in the town of East Kingston, but most of the lake lies in the town of Kingston. The Powwow River, the outlet of the pond, flows to the Merrimack River in Amesbury,...

 and passes into the southwest corner of East Kingston

East Kingston, New Hampshire

East Kingston is a town in Rockingham County, New Hampshire, United States. The population was 2,357 at the 2010 census.-History:East Kingston was once a part of Kingston called Kingston East Parish, but was granted a separate charter in 1738 by Massachusetts Colonial Governor Jonathan Belcher,...

, flowing over Trickling Falls Dam at Route 107

New Hampshire Route 107

New Hampshire Route 107 is a long north–south state highway in New Hampshire. It connects Laconia in the Lakes Region with Seabrook on the Atlantic coast....

. The river turns southeast and enters South Hampton

South Hampton, New Hampshire

South Hampton is a town in Rockingham County, New Hampshire, United States. The population was 814 at the 2010 census. South Hampton is home to Cowden State Forest and Powwow River State Forest.- History :...

, where it flows into Tuxbury Pond

Tuxbury Pond

Tuxbury Pond is a lake which straddles the Massachusetts-New Hampshire border, abutting the towns of Amesbury, Massachusetts and South Hampton, New Hampshire. It is located along the Powwow River. It has two islands in the middle, and a large summer camp resort lies along the Massachusetts shore....

 and crosses into Amesbury, Massachusetts

Amesbury, Massachusetts

Amesbury is a city in Essex County, Massachusetts, United States. Though it officially became a city in 1996, its formal name remains "The Town of Amesbury." In 1890, 9798 people lived in Amesbury; in 1900, 9473; in 1910, 9894; in 1920, 10,036; and in 1940, 10,862. The population was 16,283 at...

. Below the outlet of the pond, the river winds easterly along the state line before entering Massachusetts for good at Lake Gardner. The river then flows through the center of Amesbury, where it drops over falls and rapids before reaching the Merrimack River.

Falls at Amesbury

The river drops approximately 90 feet (27.4 m) through the center of Amesbury, providing ample water power for the early industrial development of the town. The falls in the center of Amesbury present interesting views, with a variety of machinery, dams, and houses surrounding the falls. The river flows under a historic building in the center of the town. During flooding, the Powwow River has made national news due to the potential destruction of historic buildings in Amesbury.

Atlantic white cedar swamp

Between Country Pond and Powwow Pond, the river is home to the most extensive complex of Atlantic white cedar swamp forest wetlands in New Hampshire. Atlantic white cedar swamps are a globally rare type of natural community. Of the 500000 acres (202,343 ha) of wetlands in New Hampshire, only about 550 acres (222.6 ha) are Atlantic white cedar swamps.

In 2004, The Nature Conservancy

The Nature Conservancy

The Nature Conservancy is a US charitable environmental organization that works to preserve the plants, animals, and natural communities that represent the diversity of life on Earth by protecting the lands and waters they need to survive....

purchased 50 acres (20.2 ha), including more than 3000 feet (914.4 m) of frontage on the Powwow River and nearly all of a large Atlantic white cedar basin swamp. In 2006, The Nature Conservancy acquired four more tracts, totaling 41.8 acres (16.9 ha) and providing 1300 feet (396.2 m) of river frontage, adding further protection to the swamp. The partners eventually hope to conserve a contiguous block of more than 900 acres (364.2 ha), safeguarding the river and its special habitats and providing opportunities for public boating, hunting, fishing and wildlife observation.

The area of the river between Country Pond and Powwow Pond is also an excellent example of a streamside fen ecosystem and is situated over one of southeastern New Hampshire’s largest and most productive aquifers.