Vegetative Measures for Streambank Stabilization:

Streambank erosion is a common problem throughout the United States. A stream naturally loses bank material and redeposits it elsewhere. However, sediment carried by the stream can decrease water quality especially for the aquatic population by covering substrate and increasing turbidity. Once begun, streambank erosion can be a chronic problem, causing continual loss of adjacent fields and pastures.

Traditional methods for controlling streambank erosion include those that retard flow and promote deposition and those that, through some form of cover, protect the streambank from additional erosion and scouring.

This brochure focuses on VEGETATIVE MEASURES for streambank stabilization. Whether planted live material, material secured along the bank, or both, vegetative material protects the bank in several ways:

• living root systems hold soil in place, increasing overall bank stability,
  increased roughness directs flow velocity away from the streambank and acts as a buffer against abrasive transported materials,
  vegetation causes sediment deposition, reducing the stream sediment load and re-establishing the streambank.

Four projects are highlighted, one in Illinois and three in Missouri. All streams exhibited common problems of severe streambank erosion, lack of sufficient riparian forest, and excessive stream bedload. Treatments included tree revetments and/or dormant woody plantings. Depending on the severity of the erosion and the location on the streambank, plantings included dormant cuttings (½ to 1 inch diameter), stakes (1 to 3 inches diameter), and posts (3 to 6 inches diameter). Length depended on the substrate. Plantings were set deep enough to maintain contact with the water table but were not completely submerged in water year round. Cost for both treatments was about $3.00 per linear foot.