Formed by the convergence of the South and West Branch in New Ipswich, the Souhegan River flows approximately 31 miles through the communities of New Ipswich, Greenville, Wilton, Milford, Amherst, and Merrimack before joining the Merrimack River. The Souhegan River is one of the largest tributaries to the Merrimack River in southern New Hampshire. Throughout history the river has provided transportation, powered early mills, supplied water for irrigation and drinking, and carried away wastes. Today the river continues to provide these services, however, there is a greater appreciation for its natural, recreational, and cultural resources.

Open Space

Despite the rapid pace of development in southern New Hampshire, large areas of undeveloped land exist along the Souhegan River in each community, particularly in the western sections of the corridor. Major parcels of undeveloped land along the river have been protected in the communities Merrimack, Amherst, Milford, Wilton, Greenville, and New Ipswich.

Geology

During the last ice age, glacial Lake Merrimack extended up the Souhegan River to Milford center leaving behind fine sands and silts that underlie the floodplains of the river. Additionally, streams flowing from melting glaciers deposited sediments in layers of similar sized grains. These geologic resources of the corridor provide many of the communities with their only source of public water supplies. The stratified drift aquifers that follow the river corridor provide a source of high quality drinking water used for public supplies by the Towns of Merrimack, Milford, and Wilton. The aquifer also supplies water for a spring water company in Wilton. Other significant geologic resources include scenic areas, particularly the gorge in Greenville, the Horseshoe in Wilton, and Wildcat Falls in Merrimack.

History

Over the years, a wide range of land uses has been found in the Souhegan River corridor. Over three hundred years ago a band of Penacook Indians settled on the banks of the river they named "Souhegan." Rough English translations of Souhegan are "river of the plains" and "river of difficult portages." A 1652 scouting report indicated there were about 50 Penacook families near the mouth of Salmon Brook and the Nashua River and many more along the banks of the Souhegan and Merrimack Rivers. In the 1700s the area became increasingly populated by European settlers. This settlement was accompanied by agrarian development of the land, the establishment of mills, and the incorporation of towns. The development of mills, largely textile, continued through the 1800s and into the early 1900s. In the 1920s, shoe factories began locating in the region further increasing the manufacturing base of the area. The prosperity of mills and factories became threatened by the end of World War II when a shift in the textile industries from northeast locations to more favorable southern climates occurred. Today, few of the communities in the Souhegan River corridor maintain a strong manufacturing role, having undergone a transition to other industries including electronics, defense, and computer firms or become redefined as "bedroom communities."

Wildlife and Plant Resources

Mammals and birds found in the Souhegan River corridor are those commonly found in southern New Hampshire. These include raccoons, skunks, muskrats, beavers, porcupines, white tail deer, woodchucks, squirrels, mice, bats, rabbits, and other indigenous species adapted to living near humans. The more rural areas of the watershed may also provide habitat for larger animals that require extensive habitat areas, or species that require solitude such as moose and black bear. Depending on the season, the river corridor is host to a wide diversity of bird species. Gulls, doves, woodpeckers, chickadees, and jays would be found throughout the year, while other species such as warblers, sparrows, wrens, swallows, robins, and several species of raptors are only seasonal residents. Other species including a variety of ducks, geese, and herons nest in the area or migrate through the corridor.

Typical plant species in the river corridor include those commonly found in southern New Hampshire such as white pine, hemlock, red maple, red oak, sycamore, and numerous species of grasses and shrubs.

Fishing

Native species of fish in the Souhegan River include brook trout, smallmouth bass, sunfish, yellow perch, suckers, and dace. In addition, the New Hampshire Fish and Game Department stock game fish annually in the river. Over 5,000 rainbow, brown, and brook trout are stocked in the Souhegan River annually.

The Souhegan River is an important part of the Merrimack River anadromous fish restoration program and is considered one of the most productive rivers in the watershed. The upper reaches of the Souhegan and its tributaries provide the appropriate habitat -- gravelly, sloping bottoms, water temperatures, oxygen levels, and food sources -- for excellent growth and survival of Atlantic salmon fry. On average, 100,000 Atlantic salmon fry are stocked in the Souhegan River annually. The dams on the river are equipped with downstream passage only at this time since natural reproduction is not expected. The Merrimack River Basin Fish Passage Action Plan for Anadromous Fish, January 1988, calls for the construction of upstream passage at the Merrimack Village dam when a specific number of shad pass through the Amoskeag dam. All other upstream passage is deferred.

Boating

The Souhegan River is recognized regionally and in New England for its whitewater kayaking and canoeing. Both the Appalachian Mountain Club’s River Guide and the New England Whitewater River Guide identify the river as good, intermediate whitewater. The rapids in the Greenville/Wilton stretch are classified as Class II, III, and IV whitewater.

For further information about the N.H. Rivers Management and Protection Program contact:

Steve Couture, Rivers Coordinator
29 Hazen Drive, PO Box 95
Concord, NH 03302-0095
(603) 271-8801