Johnston Dam is an earth dam built on the Trib TO Des Moines River and is located in Keosauqua, Iowa. It was built in 2005 for the purpose of grade stabilization.
The dam is privately owned by Mike Johnston.
Johnston Dam is privately owned by Mike Johnston.
|Dam length||220 feet|
|Dam height||29 feet|
|Max discharge||137 cubic feet per second|
|Max storage||29 acre feet|
|Normal storage||18 acre feet|
|Surface area||2 acres|
|Drainage area||0 square miles|
Length of the dam is defined as the length along the top of the dam. This also includes the spillway, powerplant, navigation lock, fish pass, etc., where these form part of the length of the dam. If detached from the dam, these structures should not be included.
Height of the dam is defined as the vertical distance between the lowest point on the crest of the dam and the lowest point in the original streambed.
Number of cubic feet per second the spillway is capable of discharging when the reservoir is at its maximum designed water surface elevation.
Maximum storage is defined as the total storage space in a reservoir below the maximum attainable water surface elevation, including any surcharge storage.
Normal storage is defined as the total storage space in a reservoir below the normal retention level, including dead and inactive storage and excluding any flood control or surcharge storage. For normally dry flood control dams, the normal storage will be a zero value.
Surface area, in acres, of the impoundment at its normal retention level.
Drainage area of the dam, in square miles, which is defined as the area that drains to a particular point (in this case, the dam) on a river or stream.
Dams assigned the low hazard potential classification are those where failure or misoperation results in no probable loss of human life and low economic and/or environ-mental losses. Losses are principally limited to the ownerâs property.
An emergency action plan is defined as a plan of action to be taken to reduce the potential for property damage and loss of life in an area affected by a dam failure or large flood.
|Distance to nearest town (miles)||3|
|NID ID (National ID)||IA04059|