Garrison Creek 98th Avenue Detention D
Garrison Creek 98th Avenue Detention D is an earth dam located in King County, Washington, built in 1996. It carries a High hazard potential classification and has a fair condition assessment.
About Garrison Creek 98th Avenue Detention D
The primary purpose of Garrison Creek 98th Avenue Detention D 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 Kent City Public Works Dept (local government). It impounds the Garrison Creek near Kent.
The dam stands 30 feet tall and stretches 900 feet across, creates a reservoir covering 1 acres, has a maximum storage capacity of 64 acre-feet, and collects water from a drainage area of 1 square miles. Completed in 1996, the structure is 30 years old.
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. Its condition is rated fair — the dam has minor deficiencies that are being addressed or do not pose an immediate safety threat. An emergency action plan is in place for this dam. The most recent inspection on record was 06/21/2023.
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 Washington 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 | Washington |
| County | King |
| Nearest City | Kent |
| River/Stream | Garrison Creek |
| Coordinates | 47.39404, -122.20981 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 30 ft |
| Dam Length | 900 ft |
| Year Completed | 1996 (30 years old) |
Storage & Hydraulics
| NID Storage | 64 acre-ft |
| Max Storage | 64 acre-ft |
| Surface Area | 1 acres |
| Drainage Area | 1 sq mi |
| Max Discharge | 216 cfs |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | Kent City Public Works Dept |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Fair |
| Last Inspection | 06/21/2023 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | WA00650 |
| Federal ID | WA00650 |
| More Info | State Dam Safety Program |