Canonsburg Lake is a lake in Canonsburg, Pennsylvania. It is an artificial lake formed by the waters of Little Chartiers Creek behind a 525 feet (160 m) long and 45 feet (14 m) high concrete dam. The dam was built in 1943 by Alcoa to create a freshwater reservoir for the Canonsburg Forging Plant, which was considered a strategic resource during World War II. In 1957, the Pennsylvania Fish and Boat Commission (PFBC) acquired the 138-acre (56 ha) property from Alcoa, which included the 76-acre (31 ha) surface area of the lake plus the dam and surrounding lands. The PFBC converted the body of water from an industrial reservoir into a recreational lake.