Guidance for Design Hydrology for Stream Restoration and Channel Stability (2017) / Chapter Skim
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Pages 28-41
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28 C h a p t e r 4 This chapter provides step-by-step guidance for each tab in the CSR Tool workbook. Chapter 5 provides two examples of running the program (one sand-bed and one gravel-bed stream)
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User Guidance for the CSr tool 29 "total" load sediment transport equations, while gravel/cobble-bed streams use bedload sediment transport relationships. There is no distinct threshold between these two channel types but rather a continuous spectrum and a mixture of many grain size groups (Montgomery and Buffington 1997)
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30 Guidelines for Design hydrology for Stream restoration and Channel Stability Transport Relationship Press the "Select" button under "Transport Relationship" to define the sediment transport equation that will be used to carry out the CSR analysis for the project (Figure 4-2)
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User Guidance for the CSr tool 31 used for the Copeland method of stable channel design in the Hydrologic Engineering Center's River Analysis System (HEC-RAS)
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32 Guidelines for Design hydrology for Stream restoration and Channel Stability Parker (1990) equation is a well-respected bedload equation for streams that is recommended when the grain size distribution consists of primarily gravel/cobble particles and less than 3% to 5% sand.
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User Guidance for the CSr tool 33 4.2 Quick Reference Guide Tab The "Quick Reference Guide" tab (Figure 4-4) can be viewed at any time to obtain a visual representation of the main concepts behind the CSR Tool analysis as presented in the CSR Tool Reference Manual (Appendix D of the final report for NCHRP 24-40)
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34 Guidelines for Design hydrology for Stream restoration and Channel Stability Step 2. Enter Flow Record This tab is designed to import flow records directly from the USGS database but is also capable of processing flow records from other sources.
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User Guidance for the CSr tool 35 4.4 Hydrology FDC Tab This tab was created to take a pre-derived FDC and consolidate it into a specified number of bins to be converted into a PDF of flows to be used in the CSR analysis. The following steps guide you in running this tab.
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36 Guidelines for Design hydrology for Stream restoration and Channel Stability in the "# of Bins" row. The program defaults to 25 bins (recommended)
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User Guidance for the CSr tool 37 Step 2. Inputs for Grain Size In Column C of the tab, enter the percentage of bed material that is finer than the grain size class in Column B
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38 Guidelines for Design hydrology for Stream restoration and Channel Stability Floodplain Enter the floodplain angle and roughness characteristics of the supply reach in Cells C17 and C18. This program models flows that break onto the floodplain as opposed to the Copeland method of HEC-RAS.
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User Guidance for the CSr tool 39 4.7 Design Reach Tab The main purpose of this tab is to define the desired design reach characteristics and set up the CSR analysis to produce stable channel design solutions. The following steps provide guidance on running this tab.
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40 Guidelines for Design hydrology for Stream restoration and Channel Stability is overbank. This value can be iterated to find the right value for the design.
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User Guidance for the CSr tool 41 4.9 Detailed Results Tab The "Detailed Results" tab will display more specific results for each slope and width combination from the "Results" page. The far left of the tab displays the discharges per bin used in the analysis and the associated effectiveness for each from the supply reach.
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