Diamond Valley Lake is a large man-made reservoir located near Hemet, California. At 4,500 acres with 26 miles of shoreline, it is one of the largest and deepest reservoirs in Southern California. The lake was created in 1999 primarily as a drinking water supply.

Paddling is restricted on Diamond Valley Lake. Only kayaks and canoes at least 10 feet long with seating inside the boat are permitted. Sit-on-top kayaks are not allowed. No body contact with the water is permitted, as it is a drinking water source.

Access is via the Diamond Valley Marina on the east side of the lake. Parking and launch fees apply. The marina has 3 courtesy docks and up to 11 launch lanes, depending on water levels. Reservations are recommended due to limited parking.

The lake offers scenic views of the surrounding Domenigoni and Rawson mountains. With depths up to 260 feet, the water stays cool year-round. The lake is known for its fishing, with largemouth and smallmouth bass, rainbow trout, catfish, and other species present.

Facilities are limited. The marina store offers basic snacks and drinks. There are no fish cleaning stations or camping facilities available. Pets are not allowed.

Diamond Valley Lake is open Wednesday through Sunday, with hours varying seasonally. All boats must undergo inspection for invasive species before launching. The maximum boat speed is 25 mph. Given the restrictions, paddlers should carefully review all regulations before visiting this drinking water reservoir.