Yellow Head Marsh Dam
Yellow Head Marsh Dam is an earth dam located in McHenry County, Illinois, built in 1990. It carries a Low hazard potential classification.
About Yellow Head Marsh Dam
Yellow Head Marsh Dam is a dam in McHenry, Illinois. The dam is owned by Illinois Department Of Natural Resources (state). It impounds the Trib Fox River near Ferndale.
The dam stands 7 feet tall and stretches 1,000 feet across, and has a maximum storage capacity of 579 acre-feet. Completed in 1990, the structure is 36 years old.
This dam has a low hazard potential classification, meaning that failure would cause minimal damage, limited primarily to the dam owner's property, with no expected loss of life. The most recent inspection on record was 08/11/2025.
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Location
| State | Illinois |
| County | McHenry |
| Nearest City | Ferndale |
| River/Stream | Trib Fox River |
| Coordinates | 42.31078, -88.23272 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 7 ft |
| Dam Height | 7 ft |
| Dam Length | 1,000 ft |
| Year Completed | 1990 (36 years old) |
Storage & Hydraulics
| NID Storage | 579 acre-ft |
| Max Storage | 579 acre-ft |
| Max Discharge | 400 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Other |
| Owner | ILLINOIS DEPARTMENT OF NATURAL RESOURCES |
| Owner Type | State |
| Hazard Classification | Low |
| Condition Assessment | Not Available |
| Last Inspection | 08/11/2025 |
| Emergency Action Plan | No |
Identifiers
| NID ID | IL50261 |
| Federal ID | IL50261 |
| More Info | State Dam Safety Program |