- left Salmon Falls River Mouth elevation 0 | Source Cochecho River | |
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- right Cochecho River, Great Bay - location Portsmouth Harbor, New Hampshire/Maine border, United States Bridges Memorial Bridge, Sarah Mildred Long Bridge, Piscataqua River Bridge, Little Bay Bridge | ||
Gundalow sailing on the piscataqua river
The Piscataqua River /pɪsˈkætəˌkwɔː, -kwə/) is a 12-mile-long (19 km) tidal river forming the boundary of the U.S. states of New Hampshire and Maine from its origin at the confluence of the Salmon Falls River and Cocheco River. The drainage basin of the river is approximately 1,495 square miles (3,870 km2), including the subwatersheds of the Great Works River and the five rivers flowing into Great Bay: the Bellamy, Oyster, Lamprey, Squamscott, and Winnicut.
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Map of Piscataqua River, United States
The river runs southeastward, with New Hampshire to the south and west and Maine to the north and east, and empties into the Gulf of Maine east of Portsmouth, New Hampshire. The last 6 miles (10 km) before the sea form Portsmouth Harbor, one of the finest harbors in the northeastern United States, despite a tidal current of around 4 knots (7.4 km/h; 4.6 mph). The cities/towns of Portsmouth, New Castle, Newington, Kittery and Eliot have developed around the harbor.
History
Named by the area's original Abenaki inhabitants, Piscataqua is believed to be a combination of peske (branch) with tegwe (a river with a strong current, possibly tidal). The first known European to explore the river was Martin Pring in 1603. Captain John Smith placed a spelling similar to "Piscataqua" for the region on his map of 1614. The river was the site of the first sawmill in the colonies in 1623, the same year the contemporary spelling "Piscataqua" was first recorded.
After the Allies' European victory in the Second World War, a German submarine flying a white flag sailed up the river, where New Hampshire state police received its captain and crew as POWs.
The Portsmouth Naval Shipyard is located on Seavey's Island in Kittery, Maine, near the Piscataqua's mouth. The dispute between New Hampshire and Maine over ownership of Seavey's Island was settled by the U.S. Supreme Court in 2001, locating the state border at the center of the river's navigable channel.