Grindstone-lost-muddy Watershed Dam B- 21
Grindstone-lost-muddy Watershed Dam B- 21 is an earth dam located in DeKalb County, Missouri, built in 1973. It carries a High hazard potential classification.
About Grindstone-lost-muddy Watershed Dam B- 21
The primary purpose of Grindstone-lost-muddy Watershed Dam B- 21 is grade stabilization. Grade stabilization dams prevent erosion by reducing the slope and velocity of water flowing through a channel. They're commonly used to stop gullies from deepening and to protect downstream land and infrastructure. The dam is owned by Grnsn-ls-md Wrsd Sbdistr (local government). It impounds the Tr-west Fork Creek near Pattonsburg.
The dam stands 34 feet tall and stretches 700 feet across, creates a reservoir covering 2 acres, has a maximum storage capacity of 316 acre-feet, and collects water from a drainage area of 25 square miles. Completed in 1973, the structure is well into its service life at over 50 years old.
This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. An emergency action plan is in place for this dam.
At 34 feet, this dam is taller than 80% of dams nationwide.
Living Downstream
If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The Missouri dam safety program can provide more specific information about emergency planning for this structure.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | Missouri |
| County | DeKalb |
| Nearest City | Pattonsburg |
| River/Stream | Tr-west Fork Creek |
| Coordinates | 39.84256, -94.37435 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 34 ft |
| Dam Height | 34 ft |
| Dam Length | 700 ft |
| Year Completed | 1973 (53 years old) |
Storage & Hydraulics
| NID Storage | 316 acre-ft |
| Max Storage | 316 acre-ft |
| Normal Storage | 166 acre-ft |
| Surface Area | 2 acres |
| Drainage Area | 25 sq mi |
| Max Discharge | 236 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Grade Stabilization |
| Owner | GRNSN-LS-MD WRSD SBDISTR |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Not Rated |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | MO10310 |
| Federal ID | MO10310 |
| More Info | State Dam Safety Program |