Parnell Creek Subwatershed Site M-6 Reservoir Report
Last Updated: December 14, 2025
Located in Woodbury, Iowa, the Parnell Creek Subwatershed Site M-6 is a local government-owned dam that serves multiple purposes, including fire protection, stock, and small fish pond management, as well as flood risk reduction.
°F
°F
mph
Wind
%
Humidity
Summary
Constructed in 1968 by the USDA NRCS, this earth dam stands at a height of 30 feet and has a length of 424 feet, providing storage for up to 105 acre-feet of water and covering a surface area of 5.4 acres. The dam is regulated by the Iowa DNR and is subject to state permitting, inspection, and enforcement to ensure its safe operation.
Despite its low hazard potential and moderate risk assessment, the condition of the Parnell Creek Subwatershed Site M-6 has not been officially rated. The dam's spillway is currently uncontrolled, and there are no outlet gates or associated structures present. While the dam has not undergone recent inspection or maintenance, it remains an essential asset for water resource management and emergency preparedness in the area. With its location on the TR-Parnell Creek river, this dam plays a crucial role in protecting downstream communities and ecosystems from potential flooding events.
Overall, the Parnell Creek Subwatershed Site M-6 represents a vital piece of infrastructure in the region, providing essential water management services and contributing to the overall resilience of the local environment. As water resource and climate enthusiasts, it is important to monitor and support the ongoing maintenance and management of this dam to ensure its continued effectiveness in mitigating flood risks and supporting water quality in the surrounding area.
Year Completed |
1968 |
Dam Length |
424 |
Dam Height |
30 |
River Or Stream |
TR-PARNELL CREEK |
Primary Dam Type |
Earth |
Surface Area |
5.4 |
Drainage Area |
4.36 |
Nid Storage |
105 |
Hazard Potential |
Low |
Foundations |
Soil |
Nid Height |
30 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
Maple River At Mapleton
|
323cfs |
West Fork Ditch At Hornick
|
80cfs |
Little Sioux River At Correctionville
|
327cfs |
Little Sioux River Near Turin
|
1040cfs |
Monona-Harrison Ditch Near Turin
|
158cfs |
Missouri River At Decatur
|
14900cfs |
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.
Parnell Creek Subwatershed Site M-6