Mississippi River Lock And Dam 25
Mississippi River Lock And Dam 25 is a concrete dam located in Lincoln County, Missouri, built in 1939. It carries a Significant hazard potential classification.
About Mississippi River Lock And Dam 25
The primary purpose of Mississippi River Lock And Dam 25 is navigation. The dam maintains water levels sufficient for boat and barge traffic, supporting commercial or recreational navigation on the waterway. The dam is owned by Usace - St. Louis District (federal). It impounds the Mississippi River near Winfield.
The dam stands 75 feet tall and stretches 26,400 feet across, creates a reservoir covering 13,000 acres, has a maximum storage capacity of 176,000 acre-feet, and collects water from a drainage area of 142,000 square miles. Completed in 1939, the structure is well-established, with more than 75 years of service.
This dam has a significant hazard potential classification, meaning that a failure could cause significant economic damage — flooding roads, bridges, or property downstream — but is not expected to result in loss of life. An emergency action plan is in place for this dam. The most recent inspection on record was 08/21/2025.
At 75 feet, this dam is taller than 97% of all dams in the United States.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | Missouri |
| County | Lincoln |
| Nearest City | Winfield |
| River/Stream | Mississippi River |
| Coordinates | 39.00433, -90.68794 |
Physical Characteristics
| Dam Type | Concrete |
| NID Height | 75 ft |
| Dam Height | 25 ft |
| Dam Length | 26,400 ft |
| Year Completed | 1939 (87 years old) |
Storage & Hydraulics
| NID Storage | 176,000 acre-ft |
| Max Storage | 176,000 acre-ft |
| Normal Storage | 176,000 acre-ft |
| Surface Area | 13,000 acres |
| Drainage Area | 142,000 sq mi |
| Spillway Type | None |
Ownership & Safety
| Purpose | Navigation |
| Owner | USACE - St. Louis District |
| Owner Type | Federal |
| Hazard Classification | Significant |
| Condition Assessment | Not Available |
| Last Inspection | 08/21/2025 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | MO10301 |
| Federal ID | MO10301 |
| More Info | State Dam Safety Program |