Bound Brook is a borough in Somerset County, New Jersey, United States, located along the Raritan River. At the 2010 United States Census, the borough's population was 10,402, reflecting an increase of 247 (+2.4%) from the 10,155 counted in the 2000 Census, which had in turn increased by 668 (+7.0%) from the 9,487 counted in the 1990 Census.
Bound Brook was originally incorporated as a town by an act of the New Jersey Legislature on March 24, 1869, within portions of Bridgewater Township. On February 11, 1891, it was reincorporated as a borough, based on the results of a referendum held on the previous day.
The area was first settled in 1681 and a community was established near the Bound Brook stream of the same name, which flows into the Raritan River via the Green Brook on the eastern side of the borough. The brook, which was mentioned as a boundary in a Native American deed, provides the source of the borough's name.
A wooden bridge over the Raritan River was erected as early as 1761 and named Queen's Bridge in 1767. Later, it became a covered bridge. During the American Revolutionary War, the bridge was used repeatedly by both sides including during the Battle of Bound Brook in 1777. In 1875, the wooden bridge was replaced by a steel pipe truss bridge. More than 100 years later, that bridge was itself replaced by a steel girder bridge in 1984, still using the old pillars. The bridge was renovated and repaved in 2007.
The Battle of Bound Brook, one of the battles in the New York and New Jersey campaign during the American Revolutionary War, occurred on April 13, 1777, and resulted in a defeat for the Continental Army, who were routed by about 4,000 troops under British command.
According to the United States Census Bureau, the borough had a total area of 1.695 square miles (4.389 km2), including 1.659 square miles (4.297 km2) of land and 0.036 square miles (0.092 km2) of water (2.10%).
The borough borders the municipalities of Bridgewater Township and South Bound Brook in Somerset County; and Middlesex Borough in Middlesex County.
Since the southern portion of the borough (including the downtown area) is a low-lying natural flood plain of the Raritan River, Bound Brook has suffered occasional severe flooding after heavy rain.