Keansburg (prounounced 'kEEns-burg') is a Borough in Monmouth County, New Jersey, United States. As of the United States 2000 Census, the borough population was 10,732. Keansburg was formed as a Borough by an Act of the New Jersey Legislature on March 26, 1917, from portions of both Middletown Township and Raritan Township (now Hazlet), based on the results of a referendum held on April 17, 1917. Keansburg is part of the Bayshore Regional Strategic Plan, an effort by nine municipalities in northern Monmouth County to reinvigorate the area's economy by emphasizing the traditional downtowns, dense residential neighborhoods, maritime history, and the natural beauty of the Raritan Bay coastline.