Hansen Dam was built by the Corps of Engineers between September 1939 and September 1940. The dam is located near the northern edge of
the San Fernando Valley on Tujunga Wash, about one mile below the confluence of the Big Tujunga Wash and the Little Tujunga Wash, and
about four miles southeast of the City of San Fernando. Located behind and around Hansen Dam are a variety of recreational facilities.
Among these include golf courses, ball fields, fishing ponds, trails, and parks. Public Works is also in the process of developing a
wildlife habitat along Big Tujunga Wash behind Hansen Dam. During times of heavy rains, Hansen Dam's recreational facilities are closed to the public.