Mill Picayune Watershed Site M-21-5 Reservoir Report
Last Updated: December 13, 2025
The Mill Picayune Watershed Site M-21-5 is a vital earth dam located in Shelby, Iowa, designed by the USDA NRCS and completed in 1980.
°F
°F
mph
Wind
%
Humidity
Summary
This watershed site plays a crucial role in fire protection, stock, and small fish pond purposes, as well as flood risk reduction. With a dam height of 45 feet and a storage capacity of 354 acre-feet, the site covers a surface area of 12.9 acres and has a drainage area of 1.13 square miles.
Managed by the Iowa DNR, this watershed site is state-regulated and undergoes regular inspections to ensure its structural integrity. The dam has a spillway type of "Uncontrolled" with a spillway width of 3 feet, posing a significant hazard potential but currently assessed as satisfactory in condition. While the risk assessment indicates a moderate level of risk, the watershed site serves as a critical resource for water management in the region, safeguarding against potential disasters and supporting the local ecosystem.
Overall, the Mill Picayune Watershed Site M-21-5 stands as a testament to effective water resource management in Iowa, contributing to water conservation, flood control, and ecosystem preservation. With its strategic location and design, this site serves as a beacon of resilience and protection for the community, highlighting the importance of sustainable practices in safeguarding our water resources amidst changing climate conditions.
Year Completed |
1980 |
Dam Length |
678 |
Dam Height |
45 |
River Or Stream |
TR-MILL CREEK |
Primary Dam Type |
Earth |
Surface Area |
12.9 |
Drainage Area |
1.13 |
Nid Storage |
354 |
Hazard Potential |
Significant |
Foundations |
Soil |
Nid Height |
45 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
Boyer River At Logan
|
417cfs |
Soldier River At Pisgah
|
112cfs |
Little Sioux River Near Turin
|
1040cfs |
Monona-Harrison Ditch Near Turin
|
158cfs |
Maple River At Mapleton
|
323cfs |
West Nishnabotna River At Hancock
|
154cfs |
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.
Mill Picayune Watershed Site M-21-5