|
Incident ID |
CA00649-2160 |
|
Dam Name |
TWAIN HARTE |
|
Downstream Hazard Potential |
S |
|
State |
CA |
|
Incident Date |
08/03/2014 |
|
Incident Type |
Non-failure |
|
Incident Driver |
Unknown |
|
Incident Mechanism 1 |
Under Investigation |
|
Incident Mechanism 2 |
|
|
Incident Mechanism 3 |
|
|
Incident Description |
The dam was built on solid granite. Very hard solid rock. On 8/3 the massive right abutment rock, exfoliated. This created a new seepage path which resulted in 50 gpm additional seepage. Previous to this there was only wet spots and no active seepage. |
|
Named Hydrologic Event |
|
|
EAP Enacted (Y/N) due to Incident |
|
|
Fatalities (Number) |
|
|
Number of People Evacuated |
|
|
Number of Habitable Structures Evacuated |
|
|
Number of Habitable Structures Flooded |
0 |
|
Other Infrastructure Impacts |
|
|
Economic Damages (in $) |
|
|
Volume released at failure (ac-ft) |
|
|
Response |
|
|
Additional Remarks or Updates |
We immediately drew down the reservoir to make a detailed inspection and as a precautionary measure. The situation is now stable and no dam safety threat. We will complete detailed analysis of the dam and abutment to figure out next steps. I think we will conclude the dam wasn¿t in danger, but we will see. |
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Incident Time |
|
|
Incident Duration |
|
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Incident Report Produced |
|
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Information Sources |
|
|
Owner Type |
P |
|
Dam Type |
MV |
|
Primary Purpose(s) |
RS |
|
EAP |
NR |
|
Year Completed |
1928 |
|
Year Modified |
0 |
|
Dam Height |
36 ft |
|
Max Storage (ac-ft) |
143 ac-ft |
|
Surface Area (acres) |
12 acres |
|
River Name |
TR SULLIVAN CR |
|
Latitude |
38.0291 |
|
Longitude |
-120.244 |
|
Regulatory Agency(ies) |
Division of Safety of Dams |
|
NID Number |
CA00649 |
|
Attachments |
Y |
