Stabilizing stream banks
When you see a stream bank with bare spots and trees falling in, it’s a sign that the bank need to be stabilized.
Paul Rodrigue is a supervisory engineer with the Natural Resources Conservation Service. He says bank erosion often happens when something in that stream channel is amiss.
"Typically it’s because something has happened either upstream in the watershed to put more water into the stream, or possibly downstream at what we call the outlet, and so the stream is trying to create a new stream size. Typically when we talk about streambank erosion, we’re treating a symptom of another problem," says Rodrigue. "But, for that particular landowner, they have to protect their land and resource."
One course of action includes adding rock over geotextile where the bank slope comes down and meets the streambed. How far the rock and geotextile goes up the bank will vary depending on the situation. However, Rodrigue discourages using rock, or rip-rap from the streambed all the way to the top of the bank. There also needs to be native vegetation so the roots can hold the soil.
He says the best is switchgrass, which grows anywhere in the United States.
"It’s a deep-rooted plant, it’s slow to get established," says Rodrigue. "But until you can get some other things going because a tree’s going to take a long time to develop a new root system, that switchgrass will put down a root system within three-years, and also provides a buffer for water."
Rodrigue recommends backing up any farming or animal grazing activity 100-feet from the bank until you get ahold of the situation. He says letting the vegetation grow in that area provides a buffer along the stream bank, which is imperative for its long-term stability.