Castle Ridge Lake Dam
Castle Ridge Lake Dam is an earth dam located in Madison County, Illinois, built in 2002. It carries a High hazard potential classification.
About Castle Ridge Lake Dam
The primary purpose of Castle Ridge Lake Dam is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Castle Ridge Estates Home Owners Assoc. (private). It impounds the Trib Mill Creek near Lebanon.
The dam stands 42 feet tall and stretches 875 feet across, creates a reservoir covering 14 acres, has a maximum storage capacity of 209 acre-feet, and collects water from a drainage area of 0 square miles. Completed in 2002, the structure is relatively new.
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. The most recent inspection on record was 09/12/2025.
At 42 feet, this dam is taller than 89% 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 Illinois 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 | Illinois |
| County | Madison |
| Nearest City | Lebanon |
| River/Stream | Trib Mill Creek |
| Coordinates | 38.66919, -89.87931 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 42 ft |
| Dam Height | 42 ft |
| Dam Length | 875 ft |
| Year Completed | 2002 (24 years old) |
Storage & Hydraulics
| NID Storage | 209 acre-ft |
| Max Storage | 209 acre-ft |
| Normal Storage | 143 acre-ft |
| Surface Area | 14 acres |
| Drainage Area | 0 sq mi |
| Max Discharge | 962 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Recreation |
| Owner | CASTLE RIDGE ESTATES HOME OWNERS ASSOC. |
| Owner Type | Private |
| Hazard Classification | High |
| Condition Assessment | Not Available |
| Last Inspection | 09/12/2025 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | IL50476 |
| Federal ID | IL50476 |
| More Info | State Dam Safety Program |