The Lamprey River flows easterly for 42 miles and empties into Great Bay in Newmarket, about eight miles west of Portsmouth. A small recreational fleet is based near the mouth of the river.

During the 1880s, Newmarket required 5,000 tons of coal annually to heat large manufacturing plants, several commercial establishments, and residential areas. Other commodities shipped to the town, including salt, iron, and cement, amounted to between 7,000 - 8,000 tons annually. Completed in 1883 to accommodate commercial shipping, the project consists of a 2.5-mile-long channel, five feet deep, extending from Great Bay to the vicinity of the Route 108 Bridge in Newmarket. The first two miles of the channel, from Great Bay to the Lower Narrows, is 100 feet wide, and the channel’s last 0.5 mile, from the Lower Narrows to the vicinity of the Route 108 Bridge in Newmarket, is 40 feet wide.

No shipping has been reported on the Lamprey River for many years.