Northwest Oregon District conducts habitat improvement project at Mill Creek

Story by Sarah Bennett, Public Affairs Officer. Photos by BLM and Jonas Parker, Hydrologist. 

Why did the cat cross the river? Or perhaps the question should be: Why did the Bureau of Land Management (BLM) build a cat bridge?

Last summer, employees from the BLM Northwest Oregon District, led by Fisheries Biologist Tony Spitzak and Hydrologist Douglass Fitting, began a habitat restoration project near Alsea, Oregon. Using logs that were left over from a nearby timber sale, they built a large woody debris structure in Mill Creek. The haphazard-looking pile of logs mimics fallen trees that would naturally divert or obstruct forest streams. 

Years of poor land management practices have degraded many streams across the country. Without a reliable source of new debris—old, fallen trees—to provide variation and structure, streams are prone to flooding and erosion. Faster water scours streambanks down to bedrock. Exposed, vertical banks can collapse and smother salmon nests.

Left on their own, streams can recover naturally, but it can take decades or even centuries for them to recover. The large woody debris structure that was built as part of the recent habitat improvement project at Mill Creek helps slow down high water, creating eddies, riffles, and pools. The stream deposits sand and gravel as its speed and strength change, creating varied habitat for fish, and with the added benefit of helping our feline friends find a freeway through the forest.

To monitor the effectiveness of their work, Spitzak and BLM Hydrologist Jonas Parker set up a wildlife camera nearby.

“We wanted to see how the new structure was working,” Parker said. “We can see if logs move during high winter flows. And once the water levels drop a bit, we’ll be able to see a bedrock stream channel transformed to gravel!”

The Northwest Oregon District worked with its partners including the Siuslaw Forest Service's stewardship fund and the Mid Coast Watershed Council on this habitat improvement project at Mill Creek.