Libby Dam
Dam in Lincoln County, Montana · Kootenai River · forms Lake Koocanusa
Height
422 ft
129 m (NID height)
Length
2,890 ft
881 m
Completed
1973
Lake Koocanusa today
2,443.96 ft
7 days ▼ 0.11 ft
Normal storage
5,809,000 acre-ft
Normal for the date
Reservoir level measured Oct 23, 2026, 11:00 AM MDT. Full level page →
Facts
- Purposes
- Hydroelectric; Recreation; Flood Risk Reduction
- Dam type
- Gravity
- Structural height
- 422 ft
- Owner
- USACE - Seattle District (Federal)
- Maximum storage
- 6,027,000 acre-ft
- Surface area
- 46,500 acres
- Hydraulic height
- 362 ft
- Drainage area
- 8,985 sq mi
- Spillway
- Controlled, 48 ft wide
- Army Corps district
- Seattle District
- Also known as
- Lake Koocanusa
- NID ID
- MT00652
Facts from the U.S. Army Corps of Engineers National Inventory of Dams, record updated Sep 29, 2026. Search NID ID MT00652 at nid.sec.usace.army.mil. Project website.