Grindstone-Lost-Muddy Watershed Dam B-20 Reservoir Report
Last Updated: December 5, 2025
Grindstone-Lost-Muddy Watershed Dam B-20, located in Pattonsburg, Missouri, is a local government-owned earth dam designed by the USDA NRCS for grade stabilization along the TR-West Fork Lost Creek.
°F
°F
mph
Wind
%
Humidity
Summary
Completed in 1973, this dam stands at a height of 22 feet and has a length of 480 feet, providing a normal storage capacity of 43 acre-feet and a maximum storage of 105 acre-feet.
With a low hazard potential and a moderate risk assessment, this dam serves its primary purpose of grade stabilization effectively. The spillway, with a width of 40 feet, is uncontrolled, allowing for a maximum discharge of 248 cubic feet per second. Despite not being state-regulated or inspected, Grindstone-Lost-Muddy Watershed Dam B-20 remains in a not rated condition according to the available data.
For water resource and climate enthusiasts, this dam serves as a crucial infrastructure in the area, contributing to flood control and water management efforts. With its earth core and stone foundation, it highlights the importance of sustainable design practices in maintaining water resources for the community.
Year Completed |
1973 |
Dam Length |
480 |
Dam Height |
22 |
River Or Stream |
TR-WEST FORK LOST CREEK |
Primary Dam Type |
Earth |
Surface Area |
3 |
Hydraulic Height |
22 |
Drainage Area |
19.2 |
Nid Storage |
105 |
Structural Height |
22 |
Outlet Gates |
None |
Hazard Potential |
Low |
Foundations |
Soil |
Nid Height |
22 |
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.
Grindstone-Lost-Muddy Watershed Dam B-20