| Dam Name | Pacoima |
| Incident Date | 2/9/1971 |
| Country | United States |
| State/Province | California |
| Dam Height (m) | 111.3 |
| Uncontrolled Release of the Reservoir | No |
| Dam Type | Arch |
| Detailed Dam Type | |
| Incident Type | Seismic |
| Incident Description | On February 9, 1971, the dam was severely shaken by an earthquake of magnitude 6.5, one of the most destructive events recorded in that area of California. The concrete arch structure survived undamaged, except for slight tilting and chord shortening. The shaking, however, resulted in partial opening of the joint between the arch and the left thrust block, and caused cracking in the thrust block and downward movement of the rock mass in the upper portion of the left abutment ridge. |
| High Level Failure Mode | Cracking/Structural Failure |
| Lessons Learned | Click Here |
| Initiating Event | Seismic |
| Initiating Event Description | On February 9, 1971, the dam was severely shaken by an earthquake of magnitude 6.5, one of the most destructive events recorded in that area of California. |
| Structures/Components | |
| Failure Mode Description | A Magnitude 6.5 earthquake caused cracking to some structures of the dam. |
| Emergency Action Plan Implemented | Unknown |
| Consequences | Consequence Data Unavailable |
| Geographic Coordinates - Decimal Degrees | 34.3350, -118.3950 |
| Normal Reservoir Storage (m3): | |
| Crest Elevation (m) |