Black Tern Marsh Dam
Low HazardNot Available ConditionEmergency Action Plan: No
Location
| State | Illinois |
| County | McHenry |
| Nearest City | MCHENRY |
| River/Stream | TRIB FOX RIVER |
| Coordinates | 42.30533, -88.24556 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 7 ft |
| Dam Height | 7 ft |
| Dam Length | 1,500 ft |
| Year Completed | 1992 (34 years old) |
Storage & Hydraulics
| NID Storage | 250 acre-ft |
| Max Storage | 250 acre-ft |
| Normal Storage | 133 acre-ft |
| Max Discharge | 21 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Recreation |
| Owner | ILLINOIS DEPARTMENT OF NATURAL RESOURCES |
| Owner Type | State |
| Hazard Classification | Low |
| Condition Assessment | Not Available |
| Last Inspection | 10/31/2023 |
| Emergency Action Plan | No |