|
Incident ID |
WY01389-3506 |
|
Dam Name |
FONTENELLE |
|
Downstream Hazard Potential |
H |
|
State |
WY |
|
Incident Date |
09/04/1965 |
|
Incident Type |
Non-failure |
|
Incident Driver |
Seepage/internal Erosion |
|
Incident Mechanism 1 |
Piping |
|
Incident Mechanism 2 |
|
|
Incident Mechanism 3 |
|
|
Incident Description |
Fontenelle Dam nearly failed on first filling in 1965. The embankment materials were placed directly over open joints in the right abutment. After a large spring runoff event, seepage from the reservoir worked its way through these joints and into the right abutment of the embankment dam. Massive sloughing occurred and within 12 hours 10,000 cubic yards of material were eroded away. |
|
Named Hydrologic Event |
|
|
EAP Enacted (Y/N) due to Incident |
|
|
Fatalities (Number) |
|
|
Number of People Evacuated |
|
|
Number of Habitable Structures Evacuated |
Unknown |
|
Number of Habitable Structures Flooded |
0 |
|
Other Infrastructure Impacts |
Other |
|
Economic Damages (in $) |
|
|
Volume released at failure (ac-ft) |
|
|
Response |
The engineers opened the large outlet works full open lowering the reservoir 4 feet per day. This was the only thing that saved the dam from failing |
|
Additional Remarks or Updates |
Flooding downstream with outlet works at full capacity. |
|
Incident Time |
7:00 PM |
|
Incident Duration |
12 Days |
|
Incident Report Produced |
Yes |
|
Information Sources |
ASDSO Decade Dam Series |
|
Owner Type |
F |
|
Dam Type |
RE |
|
Primary Purpose(s) |
FHRS |
|
EAP |
Y |
|
Year Completed |
1963 |
|
Year Modified |
1989 |
|
Dam Height |
139 ft |
|
Max Storage (ac-ft) |
405160 ac-ft |
|
Surface Area (acres) |
8058 acres |
|
River Name |
GREEN RIVER |
|
Latitude |
42.0286 |
|
Longitude |
-107.867 |
|
Regulatory Agency(ies) |
SEO |
|
NID Number |
WY01389 |
|
Attachments |
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