In 1981, during low water conditions in San Luis Reservoir, a long segment of the upstream face of the dam partially collapsed, causing of material to fall into the reservoir. Since the reservoir was at a low level the dam was in no immediate danger of failure, however it could not be safely refilled until the damage was repaired. By August 1982, the area had been stabilized with of additional fill (known as a "buttressing berm"), at a cost of $6.1 million. In July 1984 another crack appeared in the dam, but it soon stabilized. No such incidents have occurred since this one.