Bank Stabilization
Potential permits required: CWA 404, Threatened & Endangered Species, NHPA, Floodplain
OUTSIDE HELP:
Bank stabilization is needed when streambanks are eroding and threatening infrastructure or buildings. The methods discussed on this sheet are generally recommended when there is not space to re-shape the streambank into a terraced natural channel design. Benefits of bank stabilization include:
• Reduces bank erosion
• Protects steep slopes
• Protects infrastructure
Bank stabilization can take many forms, including riprap/stone armoring, boulder toes and log toes. Boulder and log toes refer to the material used to stabilize the ‘toe,’ or bottom edge of the streambank.
All of these methods often require a significant amount of earthwork in the stream channel. The project must be engineered to withstand the anticipated flows of the stream. This includes selecting appropriate rock or log sizes, along with the method of stabilizing them into the stream bank. Environmental consultants and/or landscape architects can help to design riparian plantings behind or in the bank stabilization areas.
Bank Stabilization with Log Toes
Bank Stabilization with Boulder Toes
Before speaking to outside resources, it will help if you have a general idea of the type of bank stabilization you are interested in. This means thinking through if you want exposed logs, boulders, willow plantings or a combination. The consultants should be able to discuss the pros and cons of each option with you in order to make a sound decision. The method chosen could be very different based upon location along the stream, as well as other criteria.
The Living Streambanks Manual provides great information on a number of bank stabilization methods that use plants and natural materials to provide stabilization. Many of the techniques in the manual will require engineering and/or permitting.
Related Objective: Bank Armoring