Olson Lake Dam
Illinois — Winnebago County — WILLOW CREEK
Location
| State | Illinois |
| County | Winnebago |
| River | WILLOW CREEK |
| Coordinates | 42.35347, -88.96268 |
Physical Characteristics
| NID Height | 24 ft |
| Dam Height | 24 ft |
| Dam Length | 1,130 ft |
| NID Storage | 630 acre-ft |
| Max Storage | 630 acre-ft |
| Surface Area | 12 acres |
Safety Classification
| Hazard Potential | Low |
| Condition Assessment | Not Available |
| EAP Status | No |
| Last Inspection | July 23, 2025 |
| Inspection Frequency | 5 |
Dam Information
| Year Completed | 1991 |
| Primary Purpose | Recreation |
| Dam Type | Earth |
| Owner Type | State |
| Owner | ILLINOIS DEPARTMENT OF NATURAL RESOURCES |
| Other Name | Rock Cut State Park Dam 2 |
Location Map
About This Dam Record
Dam safety data is maintained by the Army Corps of Engineers National Inventory of Dams (NID). High-hazard dams are those where failure could cause loss of life or major property damage downstream.