Lake Koocanusa

Name: Lake Koocanusa (Montana) water level
Creator: U.S. Army Corps of Engineers

Montana · USACE gauge

Grey bar: 12-month range 2,369.3–2,448.9 ft; red line: full pool 2,459.0 ft.

Water level · NGVD29

2,443.93FT

Gauge elevation · no % full published

7 days −0.15 ft30 days −0.50 ftvs last year −0.46 ft

Reading for Oct 25, 2026, 20:00 UTC · page refreshed Oct 25, 21:53 UTC
Source: U.S. Army Corps of Engineers (CWMS Data API)

Worth going today?This Afternoon

Looks good

Light wind, dry

Wind3 mph

Rain0%

Temp54°F

Level2,443.9 ft

This AfternoonPartly Sunny · 54°F
ENE 3 mph · rain 0%

TonightMostly Cloudy · 29°F
N 3 mph · rain 0%

Lake is 15.1 ft below its conservation pool; some ramps may be out of the water – check with the Corps project office.

NWS forecast for the gauge location. Good = wind ≤ 10 mph and rain ≤ 30%; storms are flagged. Not safety advice – check local conditions, closures and warnings.

Level history

30 days1 year

Field notes

Lake Koocanusa's latest daily level (Oct 25, 2026) is 2,443.93 (NGVD29) ft.

That is 15.07 ft below the conservation (full) pool elevation of 2,459.00 ft.

Over the past 7 days the lake has been falling (−0.15 ft), and it is −0.50 ft over 30 days.

Compared with a year ago (2,444.39 ft), the lake is 0.46 ft lower.

Readings are the hourly pool elevation the U.S. Army Corps of Engineers publishes for LIBBY DAM (NWDP); changes compare readings at the same hour.

Lake facts

Gauge / station	LIBBY DAM (NWDP)
Elevation datum	ft (NGVD29)
Gauge location	48.4117, -115.3083

Reference levels

Level · source	Elevation	Today vs level
Top of conservation pool USACE “Top of Normal”	2,459.00 ft	−15.07 ft
Top of flood-control pool USACE “Top of Flood”	2,459.00 ft	−15.07 ft
Top of inactive pool (minimum) USACE “Bottom of Normal”	2,287.00 ft	+156.93 ft
Top of dam USACE “Top of Dam”	2,472.00 ft	−28.07 ft

Only levels the agency publishes, or that we compute directly from its own records, are listed. “Today vs level” = latest reading minus the reference level. A level the source does not publish is left out rather than estimated.

Nearby lakes

Hungry Horse Reservoir60 mi E3,540.53 ft−1.23 ft Flathead Lake72 mi SE2,891.62 ft−0.32 ft Lake Sherburne87 mi E4,745.45 ft+0.70 ft Gibson Reservoir130 mi SE4,611.30 ft−1.47 ft Dworshak Reservoir139 mi S · ID1,515.46 ft−1.05 ft

Common questions

How full is Lake Koocanusa right now?

The Corps feed we use gives pool elevation, not percent full. On Oct 25, 2026 the lake was at 2,443.93 ft, 15.07 ft below the top of conservation pool of 2,459.00 ft.

How high can Lake Koocanusa go before flood storage is full?

The U.S. Army Corps of Engineers lists the top of the flood-control pool at 2,459.00 ft.

What is full pool at Lake Koocanusa?

The conservation (full) pool elevation published by the U.S. Army Corps of Engineers is 2,459.00 ft. The lake is currently 15.07 ft below it.

Is Lake Koocanusa rising or falling?

Over the last 7 days it changed −0.15 ft and over 30 days −0.50 ft.

How often is this page updated?

The page is rebuilt automatically every day from USACE's published data. Values can be revised later by the source agency.

Where does the data come from?

The U.S. Army Corps of Engineers' public CWMS Data API (cwms-data.usace.army.mil), which publishes pool elevations and the project's reference levels. Forecasts come from the National Weather Service.

Hourly pool elevation published by the U.S. Army Corps of Engineers; 7-day, 30-day and year-ago changes compare readings at the same hour. USACE data are provisional and subject to revision. This page is not affiliated with or endorsed by the U.S. Army Corps of Engineers. See data sources.