Southwest Genesee Street Detention Dam

Longfellow Creek· King, Washington· Built 1974· Earth·
High Hazard Flood Risk Reduction Public Utility

Key Takeaway

Southwest Genesee Street Detention Dam is classified as high hazard in Washington. It was completed in 1974 and is 52 years old. Its primary use is flood risk reduction. High hazard means loss of life is likely if the dam fails — it does not indicate the dam's current condition. Learn more.

Physical Details

Dam Length230 ft
Dam TypeEarth
Max Storage52 acre-ft
Normal Storage19 acre-ft
Surface Area16 acres
Drainage Area3 sq mi
Max Discharge240 cfs
Year Completed1974 (52 years old)
NID IDWA00380

Safety Information

High Hazard

Loss of human life is likely if the dam fails.

Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?

Emergency Action Plan: Yes
Last Inspection: September 5, 2023
State Regulated: Yes
Regulatory Agency: Washington Dept of Ecology

Ownership

Seattle Public Utilities

Public Utility

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Southwest Genesee Street Detention Dam?

Southwest Genesee Street Detention Dam is classified as High Hazard. Loss of human life is likely if the dam fails. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Southwest Genesee Street Detention Dam?

Southwest Genesee Street Detention Dam is owned by Seattle Public Utilities (Public Utility). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Southwest Genesee Street Detention Dam built?

Southwest Genesee Street Detention Dam was completed in 1974, making it 52 years old. Many U.S. dams were built between the 1930s and 1970s during a period of major infrastructure investment.

What is the primary purpose of Southwest Genesee Street Detention Dam?

Southwest Genesee Street Detention Dam serves the following purposes: Flood Risk Reduction. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

When was Southwest Genesee Street Detention Dam last inspected?

Southwest Genesee Street Detention Dam was last inspected on September 5, 2023. Inspection dates indicate when a formal review occurred, not the results of that inspection.

Data from the National Inventory of Dams (NID) maintained by the US Army Corps of Engineers. Dam conditions may have changed since the last update. This site is not affiliated with USACE. Do not use for emergency planning — contact your local dam safety program.