South Lake Dam
South Lake Dam is an earth dam located in McHenry County, Illinois, built in 1965. It carries a Low hazard potential classification.
About South Lake Dam
The primary purpose of South Lake Dam is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Turnberry Country Club (private). It impounds the Trib South Branch Kishwaukee River near Huntley-offstream.
The dam stands 16 feet tall and stretches 500 feet across, and has a maximum storage capacity of 119 acre-feet. Completed in 1965, the structure is well into its service life at over 50 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 10/29/2025.
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Location
| State | Illinois |
| County | McHenry |
| Nearest City | Huntley-offstream |
| River/Stream | Trib South Branch Kishwaukee River |
| Coordinates | 42.21386, -88.38278 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 16 ft |
| Dam Height | 16 ft |
| Dam Length | 500 ft |
| Year Completed | 1965 (61 years old) |
Storage & Hydraulics
| NID Storage | 119 acre-ft |
| Max Storage | 119 acre-ft |
| Normal Storage | 98 acre-ft |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Recreation |
| Owner | TURNBERRY COUNTRY CLUB |
| Owner Type | Private |
| Hazard Classification | Low |
| Condition Assessment | Not Available |
| Last Inspection | 10/29/2025 |
| Emergency Action Plan | No |
Identifiers
| NID ID | IL00589 |
| Federal ID | IL00589 |
| More Info | State Dam Safety Program |