Indian Valley Reservoir is a human-made lake in Lake County, California, 27 mi west of Williams, United States, near State Route 20. The 301000 acre.ft capacity reservoir was created by the construction of the Indian Valley Dam across the north fork of Cache Creek in 1975. The 965 ft long and 201 ft high earth-fill dam was built for water storage, irrigation and flood control. Although the reservoir is in Lake County, it was built by neighboring Yolo County, which owns all water rights to the 300600 acre.ft of water. The dam includes a hydroelectric plant. The cost of the dam and reservoir exceeded $9 million and were funded in part by two bond issues.

Recreation area

The reservoir is in the Bureau of Land Management's Walker Ridge Recreation Area. All types of recreation are allowed, including boating, camping, fishing, hunting, hiking, bicycling and horseback riding. There are two primitive boat/hike-in campgrounds, Blue Oaks and Kowalski. The area's flora and fauna include manzanita, oak and pine trees, blacktail deer, black bear, and wild turkey. Rare plants such as the Indian Valley Brodiaea and Adobe lily grow here.