By Montana Grant

Posted: May 24, 2018

North west Energy is currently “flushing” the Madison River. Now that Hegben Lake Dam is fully repaired and functional again, NW Energy is releasing water to flush the fine sediments from the gravels in the river.

The Madison River Flow Program is licensed to make sure that the flows maintain a healthy fishery throughout the Madison River. These gradual releases began on May 20th and are designed to coincide with other natural runoff releases from snowmelt and the West Fork of the Madison runoff.

Any change in flows is significant and must mimic natural seasonal flows. The release is planned to protect the outlet of Quake Lake from erosion. The goal is to release water at slightly below 3500 cfs at the Kirby Gauge, near the West Fork of the Madison River.

Fishing this flushed river will mean off color water and strong currents. Fishermen need to adjust to the conditions. The release is designed to flush sediments off gravel beds that are needed for trout spawning. The diversity of Madison River fish spawn at several times of the year, not just the Spring and Fall.

The snowpack this year has been exceptional and allows for this release. Even after the release, there will be enough water to fill Hegben Reservoir. For now, boaters on Hegben Lake need to be aware of shallow humps and shores.

Releases are currently 1,700 cfs from the dam and could increase to 2,500 cfs. By May 26th. More water will also deter Whirling Disease issues in the watershed.

Any questions about this Big Flush should be directed to NW Energy representative Amy Welsh at 406-444-8115.

Northwester Energy operates Hegben Lake and Madison River Dams under a license issued by the FERC.

Quality water flows and temperatures are essential for a quality trout fishery. Clean and abundant gravels support ideal spawning sites and promotes insect populations.

Expect excellent fishing after the Flush is complete and throughout the summer.

Don’t get Mad, get fishing!

Montana Grant

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