The imacts of dams on stream ecosystems are reviewed in this paper and examined in a case study of San Francisquito Creek, Santa Clara and San Mateo Counties, California. Searsville Dam, located on Jasper Ridge Biological Preserve, impacts the San Francisquito Creek ecosystem and species of concern within the drainage by allowing exotic species to persist and disrupting upstream-downstream flow of organisms, nutrients, and sediment. Five options are evaluated for their potential in restoring ecological integrity lost with the presence of Searsville Dam: no action, dredging the lake, draining and dredging the lake, lowering the dam, and completely removing the dam. Dam lowering is recommended because it would immediately relieve pressures on native species of concern and would spare the costs and risks associated with managing the accumulated sediment in Searsville Lake. Adaptive management of dam lowering is also recommended. Monitoring ecosystem changes with dam lowering and adapting management practices in response will provide valuable data for future dam removals and insure that species of concern are not adversely impacted.