Thorton Quarry Gap Dam
Illinois — Cook County — THORNTON QUARRY
Location
| State | Illinois |
| County | Cook |
| River | THORNTON QUARRY |
| Coordinates | 41.57987, -87.61897 |
Physical Characteristics
| NID Height | 116 ft |
| Dam Height | 116 ft |
| Dam Length | 220 ft |
| NID Storage | 9,900 acre-ft |
| Max Storage | 9,900 acre-ft |
| Surface Area | — |
Safety Classification
| Hazard Potential | High |
| Condition Assessment | Not Available |
| EAP Status | Yes |
| Last Inspection | May 13, 2025 |
| Inspection Frequency | 1 |
Dam Information
| Year Completed | 2013 |
| Primary Purpose | Flood Risk Reduction |
| Dam Type | Concrete |
| Owner Type | Private |
| Owner | METROPOLITAN WATER RECLAMATION DISTRICT |
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.