MOCCASIN LOWER - CA00122-3257
| Incident ID | CA00122-3257 |
| Dam Name | MOCCASIN LOWER |
| Downstream Hazard Potential | H |
| State | CA |
| Incident Date | 03/22/2018 |
| Incident Type | Non-failure |
| Incident Driver | Other |
| Incident Mechanism 1 | Insufficient Spillway Capacity |
| Incident Mechanism 2 | Reservoir Overfilling |
| Incident Mechanism 3 | Spillway Erosion/head Cutting |
| Incident Description | Blockage of Moccasin Creek Bypass Tunnel caused sudden rise of the reservoir above core wall to nearly the dam crest because of insufficient spillway capacity. More in Remarks. |
| Named Hydrologic Event | |
| EAP Enacted (Y/N) due to Incident | Yes |
| Fatalities (Number) | 0 |
| Number of People Evacuated | 20 |
| Number of Habitable Structures Evacuated | 1 |
| Number of Habitable Structures Flooded | 1 |
| Other Infrastructure Impacts | Water/sewer lines |
| Economic Damages (in $) | $25 million to $50 million |
| Volume released at failure (ac-ft) | |
| Response | Immediate response by dam owner, Division of Safety of Dams, and first responders. |
| Additional Remarks or Updates | Fish Hachery immediately downstream was evacuated - likely less than 20 people |
| Incident Time | |
| Incident Duration | 2 days |
| Incident Report Produced | Yes |
| Information Sources | CA DSOD |
| Owner Type | L |
| Dam Type | RE |
| Primary Purpose(s) | HOS |
| EAP | Y |
| Year Completed | 1930 |
| Year Modified | 0 |
| Dam Height | 60 ft |
| Max Storage (ac-ft) | 554 ac-ft |
| Surface Area (acres) | 29 acres |
| River Name | MOCCASIN CREEK |
| Latitude | 37.8123 |
| Longitude | -120.306 |
| Regulatory Agency(ies) | DWR, SAFETY OF DAMS |
| NID Number | CA00122 |
| Attachments |
