 | 11/15/1992 | Rockfall | Steel | Penstock rupture by a rockfall | Steel flowline ruptured by boulder.
| No significant environmental damage. Loss of generation for two days. |
| 02/09/1993 | | | Penstock intake leak | Leak at penstock intake | No significant environmental damage |
| 03/05/1993 | Needle Valve Failure | | Needle valve housing failure | Failure of a penstock needle valve housing caused flooding of the powerhouse. | Temporary loss of generation, minor embankment erosion, and minor oil pollution. |
| 03/08/1993 | | | Penstock separation at the joints | Penstock separation | None |
| 05/10/1993 | Landslide | | Penstock rupture due to a landslide | Landslide ruptured section of penstock | Project offline from October 1993 to November 1997 |
| 05/13/1993 | | | Penstock expansion joint failure | Failure of penstock expansion joint. | Loss of generation. |
| 05/17/1993 | Canal Embankment Slide | Canal | Canal embankment failure | Slump of canal embankment at penstock intake structure. | Loss of generation. |
| 05/19/1993 | Slope Failure | | Slope Failure | Moderate slope failure of natural bank on east side of penstock bed - 1,200 feet downstream of dam. | None. |
| 08/02/1993 | | | Penstock Leak | Leak in Unit No. 2 penstock caused sinkhole in ground area over leak. | Loss of generation in one of the project's three units. |
| 11/08/1993 | Water Stop Failure | | Water Stop Leak | Failure of water stops in the intake structure construction joints. | Rapid rise in piezometric levels in the embankment downstream of the intake, with plumes of muddy discharge from embankment drains. |
