Hawthorne Hills Dam
Hawthorne Hills Dam is an earth dam located in Madison County, Illinois. It carries a High hazard potential classification.
About Hawthorne Hills Dam
The primary purpose of Hawthorne Hills Dam is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Hawthorne Hills Development, Llc (private). It impounds the Trib East Mooney Cr near Edwardsville.
The dam stands 21 feet tall and stretches 1,200 feet across, creates a reservoir covering 4 acres, has a maximum storage capacity of 48 acre-feet, and collects water from a drainage area of 0 square miles.
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. Notably, no emergency action plan is currently on file for this high-hazard dam. The most recent inspection on record was 08/20/2025.
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 | Edwardsville |
| River/Stream | Trib East Mooney Cr |
| Coordinates | 38.78034, -89.93011 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 21 ft |
| Dam Height | 21 ft |
| Dam Length | 1,200 ft |
Storage & Hydraulics
| NID Storage | 48 acre-ft |
| Max Storage | 48 acre-ft |
| Normal Storage | 14 acre-ft |
| Surface Area | 4 acres |
| Drainage Area | 0 sq mi |
| Max Discharge | 514 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Recreation |
| Owner | HAWTHORNE HILLS DEVELOPMENT, LLC |
| Owner Type | Private |
| Hazard Classification | High |
| Condition Assessment | Not Available |
| Last Inspection | 08/20/2025 |
| Emergency Action Plan | No |
Identifiers
| NID ID | IL50702 |
| Federal ID | IL50702 |
| More Info | State Dam Safety Program |