Trenton Lake Upper Dam
Trenton Lake Upper Dam is an earth dam located in Grundy County, Missouri, built in 1963. It carries a High hazard potential classification.
About Trenton Lake Upper Dam
The primary purpose of Trenton Lake Upper Dam is flood risk reduction. The dam is designed to control downstream flooding by temporarily storing excess water during storms and releasing it at a controlled rate. The dam is owned by Trenton Lake Association (private). It impounds the Tr Muddy Creek near Trenton.
The dam stands 34 feet tall and stretches 1,330 feet across, creates a reservoir covering 67 acres, has a maximum storage capacity of 1,256 acre-feet, and collects water from a drainage area of 577 square miles. Completed in 1963, 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. The most recent inspection on record was 08/14/1979. That was 46 years ago — unusually long for a high-hazard dam, which typically requires more frequent inspections.
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 | Grundy |
| Nearest City | Trenton |
| River/Stream | Tr Muddy Creek |
| Coordinates | 40.07945, -93.57937 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 34 ft |
| Dam Height | 34 ft |
| Dam Length | 1,330 ft |
| Year Completed | 1963 (63 years old) |
Storage & Hydraulics
| NID Storage | 1,256 acre-ft |
| Max Storage | 1,256 acre-ft |
| Normal Storage | 690 acre-ft |
| Surface Area | 67 acres |
| Drainage Area | 577 sq mi |
| Max Discharge | 109 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | TRENTON LAKE ASSOCIATION |
| Owner Type | Private |
| Hazard Classification | High |
| Condition Assessment | Not Rated |
| Last Inspection | 08/14/1979 |
| Emergency Action Plan | Not Required |
Identifiers
| NID ID | MO10365 |
| Federal ID | MO10365 |
| More Info | State Dam Safety Program |