Coffeen Southwest Detention Pond Dam
Low HazardNot Available ConditionEmergency Action Plan: No
Location
| State | Illinois |
| County | Montgomery |
| Nearest City | GREENVILLE |
| River/Stream | TRIB MCDAVID BRANCH |
| Coordinates | 39.06701, -89.40348 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 23 ft |
| Dam Height | 23 ft |
| Dam Length | 350 ft |
| Year Completed | 2010 (16 years old) |
Storage & Hydraulics
| NID Storage | 86 acre-ft |
| Max Storage | 86 acre-ft |
| Normal Storage | 42 acre-ft |
| Surface Area | 4 acres |
| Drainage Area | 0 sq mi |
| Max Discharge | 84 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | DYNEGY MIDWEST GENERATION, INC. |
| Owner Type | Public Utility |
| Hazard Classification | Low |
| Condition Assessment | Not Available |
| Last Inspection | 09/17/2025 |
| Emergency Action Plan | No |