Irvine Lake, reservoir in Silverado, California, United States

Irvine Lake is a man-made reservoir in California situated at the base of Cleveland National Forest, covering roughly 700 acres with steep rocky cliffs and quiet coves. The lake collects water from Santiago Creek and surrounding mountains, and is managed by the Irvine Ranch Water District to supply water for nearby towns, homes, and farming.

Santiago Dam was built between 1929 and 1931 by the Irvine Company and the Serrano Irrigation District, forming what was first called Santiago Reservoir. The fishery opened to the public in 1941. After the 2016 closure over a financial dispute, OC Parks, the Serrano Water District and the Irvine Company agreed in August 2019 to reopen the lake for shore fishing.

The reservoir was originally named Santiago Reservoir after Santiago Creek, the stream it impounds; the Irvine Lake name came later. Its fishery opened to the public in 1941, stocked with largemouth bass, catfish, trout and crappie, and anglers have fished its shore ever since. The land around the water is owned by the Irvine Company, which leases the fishing, boating and camping concessions to SWD Recreation Inc.

Access is via Santiago Canyon Road from Orange toward Silverado, with Cleveland National Forest along the northeast shore. The lake reopened in August 2019 for shore fishing and other activities under a one-year agreement between OC Parks, the Serrano Water District and the Irvine Company. The surrounding land belongs to the Irvine Company, which leases the fishing, boating and camping concessions to SWD Recreation Inc.

The lake's fishery opened to the public in 1941, after the dam was finished in 1931 and fish such as catfish and largemouth bass were stocked. The Irvine Company owns the surrounding land and leases the fishing, boating and camping concessions to SWD Recreation Inc.