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Town of Somersworth
State: NH
County: Strafford


Water District Drinking Water Source

Cocheco River Watershed

Blackwater Brook crosses into Somersworth from Rochester, near a parking lot on Whitehouse Road. It runs through a three quarter mile stretch of forest, and then passes several homes on Old Rochester Dover Road. The brook crosses this road, and passes several more houses on Blackwater Road. It then passes through a culvert under the road, and crosses into Dover on its way to join the Cocheco River.

Twombly Brook flows out of a small forested wetland on Somersworth’s southern border with Rollinsford, east of Green Street. It runs along the edge of a large lawn and then crosses into Rollinsford.

Salmon Falls River Watershed

Willand Pond lies at the southern tip of Somersworth, in a densely developed area along High Street. It sits on Somersworth’s border with Dover, and is mostly surrounded by buildings, roads, and parking lots. The north shore of the pond is forested, and here a small stream flows north, through dense residential development along Blackwater Road. The stream runs through a small emergent wetland, east of Somersworth center, and then joins Tates Brook near a school on West High Street. This brook passes under the street and crosses a large farm field, where it spreads out in an area of beaver activity. It then flows past a few homes and through a culvert on Rocky Hill Road. Tates Brook forms a small pond on the edge of a large farm, as it backs up behind a bridge on the New Hampshire Northcoast Railroad tracks, and then joins the Salmon Falls River.

Lily Pond is located in northern Somersworth, surrounded by homes on Coles Pond Prow and Lily Pond Road. A small stream flows out of the north end of the pond, and makes its way through a half mile of forest, until it meets the New Hampshire Northcoast Railroad tracks near a small gravel pit. The stream then passes under the tracks and flows through another half mile of forest to meet the Salmon Falls River.

The Salmon Falls River forms Somersworth’s eastern border with Maine. It flows over an old dam and passes through a low density residential area along Salmon Falls Road. The river passes under a bridge on Salmon Falls Road and flows past two large farms and a half mile of forested wetland, before it reaches an area of dense development across from Berwick, Maine. Here the New Hampshire Northcoast Railroad tracks run along the rivers edge, as it passes over two dams at the General Electric Company hydro power facility on Main Street. The river continues to encounter dense development as it pools behind a third dam on Buffumsville Road, and then passes the Somersworth Wastewater Treatment Plant. The Salmon Falls River winds around a small forested hill and then crosses into Rollinsford.

To see the locations of these resources in Google Earth follow this link.

If you do not have Google Earth software you may download it by following this link.

Water District: Somersworth Water District
District Website: (603) 692-2268
Water Source: Salmon Falls River
# Accts Serv: 3000
Other Towns: none
Sewer District: Somersworth
District Website: (603) 692-4266?
Receiving Waters: Salmon Falls River
# Accts Serv: 11736 pop.
Other Towns: none
Sewer District: Somersworth
District Website: (603) 692-4266?
Receiving Waters: Salmon Falls River
# Accts Serv: 11736 pop.
Other Towns: none
(Click the Title of the article to learn more.)
Somersworth Master Plan
Publications, Websites, and Tools
Master Plan for the Town of Somersworth, NH.

Somersworth Master Plan Appendices
Publications, Websites, and Tools
Appendices to the Master Plan for the Town of Somersworth, NH.

Seal:town seal, click to enlarge
Population:11783 (U.S. Census Est. 2006)
Area:9.8 square miles


Somersworth is a small city along the Salmon Falls River, with an expanding urban center and several sprawling commercial and residential areas. With an estimated population of 11,783 residents in 2006, Somersworth is significantly smaller than the neighboring cities of Dover and Rochester. However, due to its small area, Somersworth’s estimated population density of 1,201 people per square mile is higher than that of its neighbors. Despite this, the town does include many pockets of natural resources, such as Willand Pond, Lily Pond, several acres of wetlands, and open space.

The city is facing the issue of fast-paced growth, manifested by loss of open space, an increase in the amount of impervious surfaces, and pressure on infrastructure. According to censes estimates, Somersworth’s population is projected to grow by only 4% by 2015. In that case it is likely that commercial development will be the driving force behind landscape change. There are two main manufacturing companies providing employment in Somersworth, but the services sector has been the main generator of jobs the last several years. Big box retailers have made their imprint on the community over the last 10 years.

As of 2007, 13% of the towns land was in current use tax status. This includes 194 acres of farmland and 570 acres of forest. However, this designation does not provide permanent protection and development incentives may decrease these numbers in the future. The town owns a number of small parcels of conservation land including Willand Pond, Parsons Park, and area adjacent to Lily Pond. The Salmon Falls River is accessible by boat above the dam in downtown Somersworth.

to learn more see The Master Plan


Somersworth was settled before 1700 as a part of Dover. It was set off and incorporated in 1754 and included Rollinsford until 1849.

Situated where the Salmon Falls River drops 100 feet over a mile, Somersworth developed into a mill town early on, beginning with gristmills and sawmills.

In 1822 a gristmill with its water rights at the Great Falls was purchased and the Great Falls Manufacturing Company was established. The company would eventually have 7 textile mills for spinning thread and weaving cotton and woolen fabrics, along the riverbank below the Great Falls. A gate house at the dam directed water as needed, regulating the flow either into the river or a company canal, which itself had gates sending it under the mill. Water power turned the wheels and belts that operated mill machinery. The railroad arrived in the early 1840s, before which goods were carted to Dover. Throughout the 19th century, other expansive brick mill buildings were erected beside the river, including a bleaching mill which was the longest running textile operation in Somersworth until it closed in 1997, and the Consolidated Light and Power Company.

Mill workers came from surrounding farms, including those in Berwick, Maine directly across the bridge, as well as new immigrants from Europe. Brick tenement row houses were rented by the company to employee families, including children before passage of child labor laws. Workers found entertainment at a number of local spots including an amusement park beside Willand Pond. In the early 1870s, the Portsmouth, Great Falls & Conway Railroad began excursions to the White Mountains. The Electric Street Railway came in 1890, allowing trolley rides to York Beach, Maine.

But the textile industry went into decline in the early 1900’s as water power was replaced with newer forms of energy, and manufacturing moved closer to cotton plantations in the south. The Great Depression sent many regional textile firms into bankruptcy, when some local facilities were adapted for shoemaking. Fire destroyed many buildings in 1939. Passenger Rail service ended in 1953.

The Great Falls Manufacturing Company's big mill was renovated for other uses in the 1980s, although the bleachery building suffered a devastating fire in November 2003, which required assistance from 23 fire departments from New Hampshire and Maine.

The Wells National Estuarine Research Reserve at Laudholm Farm, Wells, Maine Copyright 2006 All rights reserved. Collaboration with NOAA CSC, Charleston SC