|
Incident ID |
SD00691-3410 |
|
Dam Name |
LAKE HANSON |
|
Downstream Hazard Potential |
L |
|
State |
SD |
|
Incident Date |
09/12/2019 |
|
Incident Type |
Failure |
|
Incident Driver |
Hydrologic/flooding |
|
Incident Mechanism 1 |
Spillway Erosion/head Cutting |
|
Incident Mechanism 2 |
|
|
Incident Mechanism 3 |
|
|
Incident Description |
Wide spread rainfall on saturated ground ranging from 5 to 10 inches between September 11-12, 2019 caused operation of the earthen secondary spillway which eroded back to the reservoir. |
|
Named Hydrologic Event |
|
|
EAP Enacted (Y/N) due to Incident |
No |
|
Fatalities (Number) |
0 |
|
Number of People Evacuated |
unknown |
|
Number of Habitable Structures Evacuated |
unknown |
|
Number of Habitable Structures Flooded |
unknown |
|
Other Infrastructure Impacts |
Roads |
|
Economic Damages (in $) |
|
|
Volume released at failure (ac-ft) |
|
|
Response |
State dam safety staff did a site visit on Sept. 17, 2019 to document. |
|
Additional Remarks or Updates |
Same issue occurred in 2007. Repair to secondary from 2007 event was of limited scope. |
|
Incident Time |
|
|
Incident Duration |
|
|
Incident Report Produced |
|
|
Information Sources |
SD Dam Safety |
|
Owner Type |
S |
|
Dam Type |
RE |
|
Primary Purpose(s) |
R |
|
EAP |
NR |
|
Year Completed |
1932 |
|
Year Modified |
1996 |
|
Dam Height |
24 ft |
|
Max Storage (ac-ft) |
340 ac-ft |
|
Surface Area (acres) |
0 acres |
|
River Name |
TR-JAMES |
|
Latitude |
43.625 |
|
Longitude |
-97.805 |
|
Regulatory Agency(ies) |
DENR |
|
NID Number |
SD00691 |
|
Attachments |
|
