South Fork Blackwater River Dam A- 1 Reservoir Report
Last Updated: December 6, 2025
South Fork Blackwater River Dam A-1, also known as Johnson # A-1 Dam, is a private earth dam located in Kingsville, Missouri.
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Summary
Built in 1964 by the USDA NRCS, this dam serves as a vital flood risk reduction structure along the East Branch of the Blackwater River. Standing at a height of 31 feet and stretching 960 feet in length, the dam has a storage capacity of 656 acre-feet and a maximum discharge rate of 2070 cubic feet per second.
Despite its high hazard potential, South Fork Blackwater River Dam A-1 is currently rated as "Not Rated" in terms of condition assessment. With a moderate risk level of 3, the dam has not undergone regular inspections since June 1980. The dam lacks outlet gates and is equipped with an uncontrolled spillway 180 feet wide. While it does not fall under state jurisdiction, this structure plays a crucial role in protecting the surrounding area from flooding events.
For water resource and climate enthusiasts, the South Fork Blackwater River Dam A-1 presents an intriguing case study in flood risk reduction and dam management. With its unique design features and historical significance, this private earth dam in Missouri continues to be a focal point for ongoing monitoring and potential risk mitigation strategies. As efforts to address the dam's condition and safety intensify, the South Fork Blackwater River Dam A-1 serves as a reminder of the importance of maintaining and safeguarding critical infrastructure in the face of changing environmental conditions.
Year Completed |
1964 |
Dam Length |
960 |
Dam Height |
29 |
River Or Stream |
E.BR.S.FK. BLACKWATER |
Primary Dam Type |
Earth |
Surface Area |
1 |
Hydraulic Height |
29 |
Drainage Area |
19.2 |
Nid Storage |
656 |
Structural Height |
31 |
Outlet Gates |
None |
Hazard Potential |
High |
Foundations |
Soil |
Nid Height |
31 |
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.
South Fork Blackwater River Dam A- 1
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