Back River (Powwow River tributary)

General data
- Name: Back River (Powwow River tributary)
- Water system: Merrimack River
- Water type: River
- Progression: Powwow River -> Merrimack River -> Gulf of Maine -> Atlantic Ocean -> Planet Earth
- Climates: Temperate
- Continents: North America
- Countries: United States of America
Description
The Back River is a 6.5-mile-long (10.5 km) river located in New Hampshire and Massachusetts in the United States. It is a tributary to the Powwow River, part of the Merrimack River watershed. Approximately 3.0 miles (4.8 km) of the river are in New Hampshire, with the remaining 3.5 miles (5.6 km) in Massachusetts.