Illinois Central Reservoir Dam
Illinois Central Reservoir Dam is an earth dam located in Jefferson County, Illinois, built in 1926. It carries a Significant hazard potential classification.
About Illinois Central Reservoir Dam
The primary purpose of Illinois Central Reservoir Dam is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Illinois Central Gulf Railroad (private). It impounds the Fourmile Creek near Mill Shoats.
The dam stands 15 feet tall and stretches 775 feet across, and has a maximum storage capacity of 874 acre-feet. Completed in 1926, 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. The most recent inspection on record was 06/02/2025.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | Illinois |
| County | Jefferson |
| Nearest City | Mill Shoats |
| River/Stream | Fourmile Creek |
| Coordinates | 38.30951, -88.73206 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 15 ft |
| Dam Height | 15 ft |
| Dam Length | 775 ft |
| Year Completed | 1926 (100 years old) |
Storage & Hydraulics
| NID Storage | 874 acre-ft |
| Max Storage | 874 acre-ft |
| Normal Storage | 421 acre-ft |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Recreation |
| Owner | ILLINOIS CENTRAL GULF RAILROAD |
| Owner Type | Private |
| Hazard Classification | Significant |
| Condition Assessment | Not Available |
| Last Inspection | 06/02/2025 |
| Emergency Action Plan | No |
Identifiers
| NID ID | IL00176 |
| Federal ID | IL00176 |
| More Info | State Dam Safety Program |