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Bank Stabilization Design Guidelines Bank Stabilization Design Guidelines Report No. SRH-2015-25 Albuquerque Area Office Science and Technology Policy and Administration (Manuals and Standards) Yuma Area Office 1.1.1 1.1.2 U.S. Department of the Interior Bureau of Reclamation Technical Service Center Denver, Colorado June 2015 Mission Statements The U.S. Department of the Interior protects America’s natural resources and heritage, honors our cultures and tribal communities, and supplies the energy to power our future. The mission of the Bureau of Reclamation is to manage, develop, and protect water and related resources in an environmentally and economically sound manner in the interest of the American public. Cover Photograph: Stream vanes on the Calapooia River, Washington. Courtesy of Scott Wright, Natural Resources Conservation Service. BUREAU OF RECLAMATION Technical Service Center, Denver, Colorado Sedimentation and River Hydraulics Group, 86-68240 Report No.: SRH-2015-25 Bank Stabilization Design Guidelines Report Prepared by: Drew C. Baird Ph.D, P.E., D.WRE, Hydraulic Engineer Sedimentation and River Hydraulics Group, Technical Service Center Lisa Fotherby Ph.D., P.E. Hydraulic Engineer Sedimentation and River Hydraulics Group, Technical Service Center Cassie C. Klumpp, M.S., P.E. Retired Hydraulic Engineer Sedimentation and River Hydraulics Group, Technical Service Center S. Michael Sculock, Ph.D., Research Scientist Department of Civil and Environmental Engineering Engineering Research Center Colorado State University. Report Peer-Reviewed by: Blair Greimann Ph.D., P.E., Technical Specialist Sedimentation and River Hydraulics Group, Technical Service Center (Reviewed chapters 1-11 and 13-14) Nathan Holste, M.S., P.E., Hydraulic Engineer Sedimentation and River Hydraulics Group, Technical Service Center (Reviewed chapter 12) 1.1.5 1.1.6 U.S. Department of the Interior Bureau of Reclamation Technical Service Center Denver, Colorado June 2015 BUREAU OF RECLAMATION Technical Service Center, Denver, Colorado Sedimentation and River Hydraulics Group, 86-68240 Report No.: SRH-2013-25 Bank Stabilization Design Guidelines Reclamation Authors: _____________ Drew C. Baird, Ph.D., P.E., D.WRE, Hydraulic Engineer Date Sedimentation and River Hydraulics Group, Technical Service Center _____________ Lisa Fotherby, Ph.D., P.E. Hydraulic Engineer Date Sedimentation and River Hydraulics Group, Technical Service Center Report Peer-Reviewed Certification: _____________ Blair Greimann, Ph.D., P.E., Technical Specialist Date Sedimentation and River Hydraulics Group, Technical Service Center (Reviewed chapters 1-11, 13 and 14) _____________ Nathan Holste, M.S., P.E., Hydraulic Engineer Date Sedimentation and River Hydraulics Group, Technical Service Center (Reviewed chapter 12) Disclaimer This document was prepared under the sponsorship of the Bureau of Reclamation in the interest of information exchange. The United States Government assumes no liability for its contents or use thereof. The contents of this report represent the views of the authors and are provided as guidelines. This report does not constitute a standard, specification, or regulation. The United States Government does not endorse products or manufacturers. Product names are included to show type and availability, and do not constitute endorsement for their specific use. Acknowledgements This document was prepared using funding from the Albuquerque Area Office, Reclamation’s Science and Technology Program, Technical Service Center Manuals and Standards, and the Yuma Area Office. Meg Jonas of the U.S. Army Corps of Engineers, and Jon Fripp of the Natural Resources Conservation Service, provided their input and review of the topics covered and practical aspects of guideline contents. Robert Padilla of the Albuquerque Area Office reviewed drafts of this guide and provided valuable comments. Peter Martin of the Technical Service Center formatted the document and organized figures and tables. These contributions are gratefully acknowledged. ii Bank Stabilization Design Guidelines Contents Page 1 Introduction ................................................................................................... 1 1.1 Challenges of Modern River Design..................................................... 1 1.2 Bank Stabilization ................................................................................. 4 1.3 Project Development ............................................................................. 5 1.4 Organization of Design Guidelines ....................................................... 6 PART I – PRELIMINARY INVESTIGATIONS AND METHOD SELECTION ............................................................................................ 9 2 Project Requirements and General Assessment ....................................... 11 2.1 Design Criteria .................................................................................... 11 2.2 Ecological Goals ................................................................................. 12 2.3 Risk Assessment ................................................................................. 13 2.4 Hydrologic Data for Site Analysis ...................................................... 14 2.5 Other Site Data .................................................................................... 17 2.6 Permitting ............................................................................................ 18 3 The Role of Geomorphology in River Projects ......................................... 21 3.1 Geomorphic Assessment ..................................................................... 22 3.2 Procedural Steps.................................................................................. 23 3.3 Geomorphic Considerations to Promote a Stable Channel ................. 24 4 Hydraulic Assessment of Energy, River Form, and Shear Forces ......... 25 4.1 Energy and Width/Depth Ratio ........................................................... 25 4.2 Energy and Complex Channels ........................................................... 26 4.3 Energy and River Form ....................................................................... 27 4.4 Computing Erosive Force and Assessing Material and Methods Suitability ...................................................................................... 34 4.5 Traditional Riprap Revetments ........................................................... 36 4.6 Sediment Analysis and Modeling ....................................................... 39 5 Scour Assessment ........................................................................................ 41 5.1 Forms of Vertical Scour ...................................................................... 41 5.2 Descriptions ........................................................................................ 41 5.3 Countermeasures ................................................................................. 47 5.4 Scour Assessment Method .................................................................. 47 5.5 Scour Computation Topics ................................................................. 51 5.6 Basis of Scour Guidelines ................................................................... 58 6 Selecting a Bank Stabilization Method ...................................................... 61 6.1 A Comprehensive Selection Process .................................................. 61 6.2 Methods............................................................................................... 63 iii Bank Stabilization Design Guidelines 6.3 Preserving the Floodplain ................................................................... 63 6.4 Hardening Banks ................................................................................. 66 6.5 Methods Combination ......................................................................... 67 6.6 Methods Selection ............................................................................... 69 PART II – DESIGN AND CONSTRUCTION ................................................. 79 7 Preserving the Floodplain ........................................................................... 81 7.1 Infrastructure Relocations ................................................................... 81 7.2 Conservation Easements ..................................................................... 82 7.3 Design Procedure ................................................................................ 83 7.4 Discussion and Recommendations ..................................................... 85 8 Re-establishing Floodplain ......................................................................... 87 8.1 Island/Bank Clearing and Destabilization .......................................... 88 8.2 Longitudinal Bank Lowering .............................................................. 96 8.3 Side Channels.................................................................................... 102 8.4 Channel Embayments ....................................................................... 108 9 Design of Vegetated, Deformable Banklines ........................................... 113 9.1 Shape and Deformable Banklines ..................................................... 114 9.2 Vegetation Bank Protection .............................................................. 117 9.3 Live Staking/Pole Planting ............................................................... 126 9.4 Fabric Encapsulated Lifts ................................................................
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