Maple Lake Dam is an earth dam located in Cook County, Illinois, built in 1918. It carries a Significant hazard potential classification.
Dam profile
NID height · 25 ft25 ft tall and 110 ft long, taller than 50% of U.S. dams with a recorded height. Height is drawn to scale against a two-story house, about 25 ft; the profile is a generic embankment section and the water level is illustrative.
About Maple Lake Dam
The primary purpose of Maple Lake Dam is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Forest Preserve District of Cook County (local government). It impounds the Trib Des Plaines River near Lemont.
The dam stands 25 feet tall and stretches 110 feet across, creates a reservoir covering 60 acres, has a maximum storage capacity of 765 acre-feet, and collects water from a drainage area of 0 square miles. Completed in 1918, the structure is over a century old.
This dam has a significant hazard potential classification, meaning that a failure could cause significant economic damage — flooding roads, bridges, or property downstream — but is not expected to result in loss of life. The most recent inspection on record was 12/23/2025.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | Illinois |
| County | Cook |
| Nearest City | Lemont |
| River/Stream | Trib Des Plaines River |
| Coordinates | 41.71546, -87.89388 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 25 ft |
| Dam Height | 25 ft |
| Dam Length | 110 ft |
| Year Completed | 1918 (108 years old) |
Storage & Hydraulics
| NID Storage | 765 acre-ft |
| Max Storage | 765 acre-ft |
| Normal Storage | 412 acre-ft |
| Surface Area | 60 acres |
| Drainage Area | 0 sq mi |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Recreation |
| Owner | Forest Preserve District of Cook County |
| Owner Type | Local Government |
| Hazard Classification | Significant |
| Condition Assessment | Not assessed |
| Last Inspection | 12/23/2025 |
| Emergency Action Plan | No |
Identifiers
| NID ID | IL00878 |
| Federal ID | IL00878 |
| More Info | State Dam Safety Program |