Conley Dam Reservoir Report
Last Updated: December 14, 2025
Conley Dam, located in Cherokee, Iowa, is a privately owned earth dam completed in 2002 by the NRCS.
°F
°F
mph
Wind
%
Humidity
Summary
With a height of 29 feet and a length of 260 feet, the dam serves multiple purposes including fire protection, stock watering, and small fish pond management. It has a storage capacity of 55 acre-feet and covers a surface area of 3.1 acres, drawing water from Coonley Creek for its reservoir.
Despite being classified as having a low hazard potential, Conley Dam is subject to state regulation, inspection, and enforcement by the Iowa Department of Natural Resources. The dam features an uncontrolled spillway with a width of 4 feet, and its risk assessment is rated as moderate (3). While the dam's condition has not been officially assessed, it is important to note that emergency action plans and risk management measures have not been documented or updated, raising concerns for potential safety issues in the event of a dam failure. For water resource and climate enthusiasts, Conley Dam offers a fascinating case study in dam management and risk assessment in the heart of the Midwest.
Year Completed |
2002 |
Dam Length |
260 |
Dam Height |
29 |
River Or Stream |
TR- COONLEY CREEK |
Primary Dam Type |
Earth |
Surface Area |
3.1 |
Drainage Area |
0.56 |
Nid Storage |
55 |
Hazard Potential |
Low |
Foundations |
Soil |
Nid Height |
29 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
Little Sioux River At Linn Grove
|
257cfs |
Little Sioux River At Correctionville
|
327cfs |
Floyd River At Alton
|
36cfs |
Ocheyedan River Near Spencer
|
59cfs |
North Raccoon River Near Sac City
|
312cfs |
Maple River At Mapleton
|
323cfs |
Dam Data Reference
Condition Assessment
SatisfactoryNo existing or potential dam safety deficiencies are recognized. Acceptable performance is expected under all loading conditions (static, hydrologic, seismic) in accordance with the minimum applicable state or federal regulatory criteria or tolerable risk guidelines.
Fair
No existing dam safety deficiencies are recognized for normal operating conditions. Rare or extreme hydrologic and/or seismic events may result in a dam safety deficiency. Risk may be in the range to take further action. Note: Rare or extreme event is defined by the regulatory agency based on their minimum
Poor A dam safety deficiency is recognized for normal operating conditions which may realistically occur. Remedial action is necessary. POOR may also be used when uncertainties exist as to critical analysis parameters which identify a potential dam safety deficiency. Investigations and studies are necessary.
Unsatisfactory
A dam safety deficiency is recognized that requires immediate or emergency remedial action for problem resolution.
Not Rated
The dam has not been inspected, is not under state or federal jurisdiction, or has been inspected but, for whatever reason, has not been rated.
Not Available
Dams for which the condition assessment is restricted to approved government users.
Hazard Potential Classification
HighDams assigned the high hazard potential classification are those where failure or mis-operation will probably cause loss of human life.
Significant
Dams assigned the significant hazard potential classification are those dams where failure or mis-operation results in no probable loss of human life but can cause economic loss, environment damage, disruption of lifeline facilities, or impact other concerns. Significant hazard potential classification dams are often located in predominantly rural or agricultural areas but could be in areas with population and significant infrastructure.
Low
Dams assigned the low hazard potential classification are those where failure or mis-operation results in no probable loss of human life and low economic and/or environmental losses. Losses are principally limited to the owner's property.
Undetermined
Dams for which a downstream hazard potential has not been designated or is not provided.
Not Available
Dams for which the downstream hazard potential is restricted to approved government users.
Conley Dam