East Fork Grand River Watershed Site B-46 Reservoir Report
Last Updated: December 14, 2025
East Fork Grand River Watershed Site B-46 is a flood risk reduction structure located in Ringgold County, Iowa, along the TR- East Fork Grand River.
°F
°F
mph
Wind
%
Humidity
Summary
Constructed in 2006 by the USDA NRCS, this earth dam stands at 29 feet high and spans 427 feet in length, providing a storage capacity of 70 acre-feet. The dam serves the primary purpose of flood risk reduction and is regulated by the Iowa DNR, with state permitting, inspections, and enforcement in place to ensure its safety and effectiveness.
Despite being rated as having a low hazard potential, the dam at Site B-46 is considered to be in moderate risk, with a risk assessment score of 3 out of 5. The condition of the structure is currently not rated, but with regular state inspections and enforcement measures in place, its safety and functionality are actively monitored. While the dam has not been modified in recent years and lacks an Emergency Action Plan (EAP), its relatively low hazard potential and ongoing state oversight contribute to its overall risk management measures.
For water resource and climate enthusiasts interested in the management and regulation of flood risk reduction structures, East Fork Grand River Watershed Site B-46 offers a case study in state-regulated dam operations. With a focus on safety and functionality, this earth dam serves as a vital piece of infrastructure in mitigating flood risks in the region, showcasing the importance of ongoing monitoring and maintenance to ensure its effectiveness in protecting surrounding communities and water resources.
Year Completed |
2006 |
Dam Length |
427 |
Dam Height |
29 |
River Or Stream |
TR- EAST FORK GRAND RIVER |
Primary Dam Type |
Earth |
Surface Area |
3.8 |
Drainage Area |
0.22 |
Nid Storage |
70 |
Hazard Potential |
Low |
Foundations |
Soil |
Nid Height |
29 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
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.
East Fork Grand River Watershed Site B-46