The Chicopee River is an 18.0-mile-long (29.0 km) tributary of the Connecticut River in the Pioneer Valley, Massachusetts, known for fast-moving water and its extraordinarily large basin: the Connecticut River's largest tributary basin. The Chicopee River originates in a Palmer, Massachusetts village called Three Rivers as a confluence of the Ware, Quaboag and Swift rivers. It passes through Wilbraham, Ludlow, and the Indian Orchard neighborhood of Springfield.

The Connecticut River is the longest river in the New England region of the United States, flowing roughly southward for 406 miles (653 km) through four states. It rises 300 yards south of the U.S. border with Quebec, Canada, and discharges at Long Island Sound. Its watershed encompasses 11,260 square miles (29,200 km2), covering parts of five U.S. states and one Canadian province, via 148 tributaries, 38 of which are major rivers. It produces 70% of Long Island Sound's fresh water, discharging at 18,400 cubic feet (520 m3) per second.