Hawthorn Parkway Dam is an earth dam located in Lake County, Illinois, built in 2001. It carries a High hazard potential classification.
Dam profile
NID height · 9 ft9 ft tall and 200 ft long. 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 Hawthorn Parkway Dam
The primary purpose of Hawthorn Parkway Dam is flood risk reduction. The dam is designed to control downstream flooding by temporarily storing excess water during storms and releasing it at a controlled rate. The dam is owned by Village of Vernon Hills (local government). It impounds the Seavey Drainage Ditch near Vernon Hills.
The dam stands 9 feet tall and stretches 200 feet across, and has a maximum storage capacity of 910 acre-feet. Completed in 2001, the structure is relatively new.
This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. An emergency action plan is in place for this dam. The most recent inspection on record was 11/20/2025.
Living Downstream
If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The Illinois dam safety program can provide more specific information about emergency planning for this structure.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | Illinois |
| County | Lake |
| Nearest City | Vernon Hills |
| River/Stream | Seavey Drainage Ditch |
| Coordinates | 42.24171, -87.96225 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 9 ft |
| Dam Height | 9 ft |
| Dam Length | 200 ft |
| Year Completed | 2001 (25 years old) |
Storage & Hydraulics
| NID Storage | 910 acre-ft |
| Max Storage | 910 acre-ft |
| Normal Storage | 475 acre-ft |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | Village of Vernon Hills |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Not assessed |
| Last Inspection | 11/20/2025 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | IL55031 |
| Federal ID | IL55031 |
| More Info | State Dam Safety Program |