Stream Restoration

On August 13 - 15, 2009, I had the opportunity to see low-impact fisheries restoration work along Hughes Creek, near the town of North Fork, Idaho.  It’s an intriguing process that, for many, seems initially counterintuitive.  Starting with an open, free-flowing stream, the biologists and their crew create various debris jams along the waterway.  “If we do a good job, we make a real mess,” paraphrases lead fisheries biologist Jo Chirstensen’s explanation of the process.

If you visit a wilderness area, however, it makes far more sense.  In wild forests, trees and branches do fall into the creeks regularly.  Biologists studying these stream ecosystems have discovered that the woody material that naturally falls into these creeks has crucial value to the stream ecosystem, changing the speed and direction of water flow, causing inorganic materials to sort, and adding nutrients to the stream.  If you take a tidy creek and load it up with trees, branches, and boughs, the stream is almost immediately better suited for a variety of native fish.

It’s a fairly straightforward process.  A few trees are felled from a nearby hillside and then dragged to the streamside by a team of draft horses.  The trees are still green, with branches intact, to better impact the water flows.  Pulleys and cables are set so the draft horses can head away from the stream while pulling the cabled logs into precise locations.  Trees are not cut right next to the stream, as healthy waterways need plenty of trees along their shores to reduce the speed of erosion and to create shade, which keeps the water cooler.  Cooler water holds more oxygen, and salmonids (which include trout and salmon) require excellent water quality and high levels of dissolved oxygen.  The constructed debris jams need to be well-anchored to withstand floodwater flows, and they need to be built with three dimensions in mind, as all streams will naturally rise and fall with the seasons and weather systems.

Draft horses are used as the power source for moving the logs into place because they cause minimal impact on the environment and their cost of operation is far less than that of heave machinery.  People enjoy watching the horses and the teamster at work, but it’s far more than an aesthetic pleasure, they truly do the best job for the least expense, both in terms of dollars and environmental impact.

Many thanks to sponsors of the project, Salmon Valley Stewardship, a vibrant organization that promotes a sustainable economy and a healthy environment in the Salmon River Region of Idaho.  The Trout Conservancy of Montana also played a key role in the planning and operation of this project, as they have with other stream restoration projects in the northern Rocky Mountains.

Hughes Creek, Salmon River Watershed, Idaho