Ross
Skagit River·
Whatcom, Washington·
Built 1949·
Concrete·
540 ft tall
Physical Details
| Dam Height | 540 ft (taller than 97.8% in WA) |
| Dam Length | 1,300 ft |
| Dam Type | Concrete |
| Max Storage | 1.5M acre-ft |
| Normal Storage | 1.4M acre-ft |
| Surface Area | 11,680 acres |
| Drainage Area | 978 sq mi |
| Max Discharge | 85,000 cfs |
| Year Completed | 1949 (77 years old) |
| NID ID | WA00169 |
Safety Information
High Hazard
Loss of human life is likely if the dam fails
Emergency Action Plan: Yes
Last Inspection: August 15, 2022
State Regulated: No
Ownership
City of Seattle
Local Government
Nearby Dams
Frequently Asked Questions
What is the hazard classification of Ross?
Ross is classified as High Hazard. Loss of human life is likely if the dam fails.
Who owns Ross?
Ross is owned by City of Seattle (Local Government).
When was Ross last inspected?
Ross was last inspected on August 15, 2022.
When was Ross built?
Ross was completed in 1949, making it 77 years old.
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.