Also in the 1950s, the construction of the James J. Lenihan Dam formed Lexington Reservoir, which flooded much of a small valley above Los Gatos, including the former townsites of Lexington and Alma. The dam and reservoir were completed in 1952, forcing the rerouting of Highway 17. When the reservoir's water level is low, the concrete bed of the old highway through those towns can be seen, along with foundations from some buildings. In spite of these events, much of the creek maintains its natural course and beauty.