By Steve Stuebner

Boise River Flood Control District #10 has completed three bank repairs over the course of the 2024-25 Winter Maintenance season.

Flood #10 officials had acquired a Flood Management Grant from the Idaho Water Resource Board for $51,975 to cover the cost of making several streambank repairs and gravel removal at a sharp corner in the Boise River near Middleton.

During the week of March 10, Flood #10 worked on a portion of the bank-stabilization  project they had planned to complete during the winter maintenance season. Permits got approved by the Idaho Department of Water Resources and U.S. Army Corps of Engineers (ACOE) on March 6^th.

Flood #10 contractors transported equipment and supplies to the project site in order to begin work on March 10. Sediment barriers had to be set up in the river ahead of the bank repairs, per permit guidelines. The repairs were completed in a two-day window, just before the Bureau of Reclamation and ACOE began flood-control releases on the Boise River on March 13.

So the construction window between obtaining permits and doing the repair was extremely tight. “There was no time to waste,” said Mark Zirschky, Flood #10 District Manager.

Flood #10 contractor Randy St. Clair Construction performed the work, and Flood #10 board member Mitch Bicandi, who leases the Mulchay farm property where the bank-repair took place, provided the heavy equipment as an in-kind match.

Now, the upstream portion of the bank repair deflects the current away from the bank into the middle of the stream channel. “The river is doing what we want it to do,” he said.

For the bank-stabilization project, Zirschky acquired lava rock from an associate in Kuna at no charge. Flood #10’s contractors hauled the rock to the project site. During construction, willow bundles were placed every 5 feet along the bank project for additional bank stabilization.

More work is planned at the Mulchay property location along the Boise River to finish the work authorized under the existing Flood Management Grant from the Idaho Water Resource Board. Several aspects of the project will need more time to get approved by the ACOE, he said.

Several additional bank barbs and gravel-removal will be needed to prevent the river flow from cutting into the streambank, Zirschky said.

“We’re trying to straighten out this corner in the Boise River a bit to reduce sedimentation and water quality issues and so things are more sustainable over time,” he said. “If you look at some aerial photos, we’re trying to restore the river channel to where it used to be.”

Two other bank repairs occurred during the winter of 2024-25 that were taken care of by private landowners, Zirschky said.

Now that the Boise River is rising for spring flood-control operations, the window for winter maintenance work has closed. Flood #10’s permit only allows in-stream work to be done during low flows. By Monday, March 24, the Boise River was running 3,740 cfs at the Glenwood Bridge in Boise.

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