EIGHTMILE LAKE OUTLET DAM - WA00228-3248
Incident ID WA00228-3248
Dam Name EIGHTMILE LAKE OUTLET DAM
Downstream Hazard Potential H
State WA
Incident Date 01/01/2019
Incident Type Non-failure
Incident Driver Deterioration Or Poor Condition
Incident Mechanism 1 Spillway Pipe Failure
Incident Mechanism 2 Insufficient Spillway Capacity
Incident Mechanism 3 Reservoir Overfilling
Incident Description No failure but EAP implemented for deteriorating 90 year old dam as precaution for high spring runoff.  Wildfire burned much of watershed the previous fall and low-level outlet was not working. Located in wilderness area with no winter access or remote monitoring.
Named Hydrologic Event
EAP Enacted (Y/N) due to Incident Yes
Fatalities (Number) 0
Number of People Evacuated 0
Number of Habitable Structures Evacuated 0
Number of Habitable Structures Flooded 0
Other Infrastructure Impacts None
Economic Damages (in $) None
Volume released at failure (ac-ft)
Response Public alert and meetings. Local and State EM staff engaged. Twice weekly recons by small aircraft/helicopters. Installed remote monitoring, re-shaped and armoroed crest, reapired low level outlet.
Additional Remarks or Updates temporary measures in place. Dam owner applying for rehabilitation of the dam. Located on USFS property.
Incident Time
Incident Duration 10 Months
Incident Report Produced No
Information Sources WA DOE
Owner Type U
Dam Type ERRE
Primary Purpose(s) IR
EAP Y
Year Completed 1933
Year Modified 0
Dam Height 22 ft
Max Storage (ac-ft) 1610 ac-ft
Surface Area (acres) 65 acres
River Name EIGHTMILE CREEK
Latitude 47.5205
Longitude -120.858
Regulatory Agency(ies) WASHINGTON, DEPT OF ECOLOGY
NID Number WA00228
Attachments
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