This report presents a description of useful environmentally sensitive channel- and bank-protection measures, design guidelines for their application, and a selection system for determining the most appropriate channel- and bank-protection measure. This report will be particularly useful to professionals responsible for design and construction of channel- and bank-protection measures in environmentally sensitive areas. Environmentally sensitive channel- and bank-protection measures—such as bioengineering, root wads, large woody debris, riparian vegetation, bendway weirs, and energy dissipaters—are being called for more frequently to protect transportation facilities from erosion, scour, and lateral migration. However, relatively little guidance has been developed to help practitioners apply environmentally sensitive channel- and bank-protection measures with confidence that their designs are adequate. Traditional channel- and bank-protection techniques rely on countermeasures such as riprap, gabions, cable-tied blocks, or grout-filled bags, which may not offer sufficient instream functions, such as habitat diversity, fish passage, water quality, and energy dissipation. The use of more environmentally sensitive measures for the protection of channels and stream banks has been hampered by the lack of selection criteria and design guidelines. Under NCHRP Project 24-19, Salix Applied Earthcare developed selection criteria, design guidelines, and a compilation of techniques used for environmentally sensitive channel- and bank-protection measures. After conducting an extensive literature review and evaluation of commonly used environmentally sensitive techniques, the research team identified 44 environmentally sensitive channel- and bank-protection techniques for study. The channel- and bank-protection techniques were grouped into four major categories, namely (1) River Training Techniques, (2) Bank Armor and Protection, (3) Riparian Buffer and River Corridor Treatments, and (4) Slope Stabilization. Technique descriptions and guidelines for their applications were developed. Finally, a rule-based technique selection system was also developed. The selection system is presented as an interactive software program entitled “Greenbank,” which can be found on the accompanying CD-ROM (CRP-CD-58). (Author/publisher) This report may be accessed by Internet users at http://gulliver.trb.org/publications/nchrp/nchrp_rpt_544.pdf
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