The San Vicente Dam is a concrete gravity dam on San Vicente Creek near Lakeside and 25 km (15.5 mi) northeast of San Diego, California. The dam was built between 1941 and 1943 and created San Vicente Reservoir for the purpose of municipal water storage, flood control and recreation. Although the reservoir is fed by run-off, its main source is the First San Diego Aqueduct. In June 2009, construction to raise the height of the dam by 117 ft (36 m), in order to more than double its reservoir size, commenced. It is the largest dam raise in the United States and largest roller-compacted concrete dam raise in the world. The dam raise project was originally set for the end of 2012, but was completed in early 2014. Efforts to replace the water supply pipelines and prepare the reservoir for the pu