01/24/2025
Let’s talk about low-tech process-based restoration (LTPBR).
Streams are dynamic. Small things can make big differences- a fallen tree, a boulder, a beaver dam. In-stream structures create diversity in habitat, create pools, riffles, increase macroinvertebrate diversity- all things trout love.
Beavers play a big part in this, they are keystone species, furry ecosystem engineers. Where beavers are present we have healthy streams, connected to their flood plains, with abundant vegetation, habitat diversity and shaded, cool water. Take beavers out of the equation, streams can degrade, become incised and drain the surrounding soil. The fur trade, habitat loss and competing land uses led to beaver numbers dropping to around 10% of what we saw in the 1800s. Today, reintroduction efforts are underway in many states, including Utah.
We can mimic the work beavers do on a stream by building Beaver Dam Analogues (BDAs). These simple structures made of wood, branches, mud and rocks imitate the work beavers would be doing on that stream.
Last summer TU helped manage projects that saw just shy of 500 BDAs built in trout streams. These create riffles, pools and runs, help prevent erosion and sediment loading, and raise the water table to encourage plant growth along the banks. Perfect for beaver, mule deer and birds.
Slides 1 + 2, 3 + 4 are before and after BDA installation, slide 5 shows a reconnected side channel, slide 6 shows beaver had got to work building on a BDA that was built a few months prior.
We work with state and federal agencies, landowners, volunteers and non-profit partners like to get this work done. Send us photos of beaver dams that have made a difference in your watershed.
