Puddingstone Dam is a high earth and rockfill dam in the San Gabriel Valley, within San Dimas in eastern Los Angeles County, California. The dam was built in 1928 by the Los Angeles County Department of Public Works, which continues to operate it. Geography Puddingstone Dam serves mainly for flood control. It impounds Walnut Creek, a tributary of the San Gabriel River, to form Puddingstone Reservoir, which can hold more than of water. The reservoir stores floodwater from both the Walnut Creek Wash, and also the San Dimas Wash, to which it is connected by a short artificial channel below San Dimas Dam. See also List of dams and reservoirs in California References Los Angeles County Department of Public Works dams Rock-filled dams San Gabriel Valley San Dimas, California Dams completed in 1928 1928 establishments in California