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AN INTRODUCTION TO STREAMBANK EROSION
 Streambank erosion is the wearing away of the soil from streambeds and banks, which occurs as a result of friction caused by flowing water. As the loose soil gets picked up and travels downstream, it gets deposited in areas normally free of sediment. The effects of sedimentation can be devastating to the surrounding land and habitat. Excess sediment in the stream is a form of nonpoint source pollution (pollution that comes from a diffuse source rather than a single point) and can suffocate fish, smother spawning beds, kill aquatic insects, impair filtration and degrade water quality. In addition, sediment may block sunlight necessary for aquatic vegetation and may contain pollutants such as pesticides, fertilizers, and metals. As one can see, the effects of erosion reach further than the loss of valuable land. Erosion threatens the surrounding habitat as well.
The primary source of streambank erosion is from soil with insufficient cover. Altering the landscape with construction, mining, forestry, grazing, and various agricultural practices can reduce vegetative cover. High flows that exceed the stream's resistance to erosion cut into the banks of the stream, increasing their steepness and dumping excess sediment into the water. Thus, a changing landscape that results in higher stream flow rates and more frequent flash floods will put the stream at risk for erosion.
THE BENEFITS OF STREAMBANK RESTORATION
WITH BIOENGINEERING TECHNIQUES
 The primary method of streambank restoration discussed in this guide involves soil bioengineering techniques. Soil bioengineering makes use of biodegradable materials and the planting of native species along streambanks to provide a natural, attractive streambank. The use of vegetation for streambank restoration has both hydrologic and habitat benefits. The "buffer zone" of vegetation surrounding the stream protects streambanks by stabilizing the soil with deep root structures, thus reducing the effects of erosion during periods of peak flow. Streambank vegetation serves to reduce runoff volume and velocity, catch precipitation, and hold moisture in the roots and soil. It also slows the release of water during the dry season. In addition to reducing the runoff that carries sediment, the plants themselves help to catch and hold some of the sediment.
Using vegetative techniques to restore streambanks has other benefits as well. It helps to improve habitat for the aquatic and semi-aquatic life supported by the stream, serve as a pollutant buffer, and act as a physical buffer against cattle and other animals that may trample or erode the streambank. In addition, bioengineering techniques provide an enduring, attractive alternative to classical engineering methods that may be economically unfeasible, technically ineffective, or otherwise unsuitable. The techniques are cost effective and environmentally friendly while providing the needed protection to the streambank.
One key to the success of our restoration projects has been following the rights steps to ensure that the materials and plants that we use are installed properly. To experience our type of streambank restoration work, and still allow you to stay dry and free of mud,
please continue on to our step-by-step virtual restoration! Click on the first photo to start the show.
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