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Libby Dam

17877 Highway 37

Libby, Montana 59923-7828

Libby Dam Office (406) 293-7751 

Kootenai River Levels Recording (406) 293-3421

For Visitor Information contact the Visitor Center (406) 293-5577



Libby Dam

Libby Dam Project is a multi-purpose water resource development.  Its purposes are flood reduction, hydropower, recreation, and environmental stewardship. We recognize that our day to day activities in operating a facility such as Libby Dam have a direct impact on the environment. Our goal is to operate Libby Dam to minimize negative impacts on the environment through pollution prevention and mitigation, and we are committed to continual improvement.  Our commitment is to comply with environmental legislation, rules, and regulations. We encourage environmental stewardship at every level throughout the organization.

Flow Update

April 22, 2015

Current Koocanusa Reservoir elevation:  2,419.4 feet
Current Koocanusa Reservoir inflow: ~8,500 cubic feet per second
Current Libby Dam outflow: 13,300 cfs
Current Kootenai River elevation at Bonners Ferry: 1,749.9 feet

Outflow from Libby Dam will decrease from 13,300 cfs to 8,000 cfs over six hours beginning at 9 p.m. MDT today.  The current plan is to pass inflow and hold the reservoir level until refill is declared.  This flow decrease is due to lower-than-forecasted flows on the Kootenai River.

The April water supply forecast for the April through August inflow volume to Libby Dam was 5.808 million-acre-feet, which is 99 percent of the 1981-2010 average.  This forecast sets the reservoir storage space requirement to 1.324 million-acre-feet prior to refill, which corresponds to a maximum reservoir elevation of 2,428.6 feet.

The Northwest River Forecast Center creates daily forecasts for short term projections throughout the Kootenai and Columbia River Basins.  These forecasts may be updated multiple times in a day and as conditions change.  Links to those forecasts can be found below.

Short term forecasts for Libby Dam elevations and inflows:

Short term forecasts for Libby Dam outflow:

Additionally, projected inflows and reservoir operations at Libby Dam through next summer can be found here:

These modeling results are updated at least monthly and include information on elevations, inflow, and outflow:

Page 1 shows Lake Koocanusa elevation probabilities through next summer
Page 2 shows Libby Dam inflow probabilities through next summer
Page 3 shows Libby Dam outflow probabilities through the summer

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