We would need to have above average rainfall to replenish Cachuma Reservoir. The long-term average rainfall is approximately 25-30 inches. For Gibraltar, it takes approximately 10 inches of rain to saturate the ground to the point that runoff could begin to flow into the reservoir. Ideally, this amount of rain would occur of a series of storm events to avoid flooding concerns. See more information about countywide Rainfall and Reservoirs.