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42 C h a p t e r 5 This chapter presents two examples of using the CSR Tool. One example is a sand-bed river using U.S. customary units and the other is a gravel/cobble-bed river using metric units. Chapter 4 focused on explaining the inputs and functions required by the user to run the CSR Tool. This chapter will provide visuals and explanations on each tab for the output of the tool. 5.1 Sand Bed This example is for a reach on Big Raccoon Creek, Indiana (Figure 5-1). The data used for this example are from Soar and Thorne (2001; Appendix B: U.S. sand-bed river data). 5.1.1 Startup Tab The CSR Tool initial screen is shown in Figure 5-2. The project information summary is optionally entered in the top right of the tab. The stream type is selected as âSand Bedâ because the D50 for this stream is 0.5 mm, which is within the range given in Table 4-2 for the Brownlie (1981) sand-bed transport equation. This range is also provided in the selection guidance window as shown in Figure 5-3. The selection for each field will display for reference below the âSelectâ buttons. The selection of a sand-bed stream type will automatically choose the Brownlie (1981) equa- tion for the transport relationship since this is the only sand-bed transport equation available for the CSR Tool. You can also select the equation manually as shown in Figure 5-4. This example reach has USGS gage data of significant length (26 years) available to represent the hydrology of the channel for calculations, so the âFlow Recordâ option was selected for âHydrology Infoâ (Figure 5-5). Lastly, the preferred units are selected as âU.S. Customaryâ for this example. This selection will update and format the tabs to accept inputs and produce outputs in this unit of choice (Figure 5-6). After the preceding four selections are made and the âStart New Projectâ button is pressed, the next required tabs necessary to run the program are displayed in the workbook as shown on the bottom of Figure 5-7. 5.1.2 Hydrology Tab To follow the steps provided in Section 4.3, the flow record information is first entered, if desired, then just the discharges of the flow record are entered in cubic feet per second. Subse- quently, the âSort Flow Recordâ button is pressed to produce results. CSR Tool Examples
Figure 5-1. Map of Big Raccoon Creek watershed in Indiana (Indiana Department of Environmental Management 2013). Figure 5-2. âStartupâ tab of the CSR Tool.
Figure 5-3. Selecting âStream Typeâ on âStartupâ tab. Figure 5-4. Selecting âTransport Relationshipâ on âStartupâ tab.
Figure 5-5. Selecting âHydrology Infoâ on âStartupâ tab. Figure 5-6. Selecting âPreferred Unitsâ on âStartupâ tab.
46 Guidelines for Design hydrology for Stream restoration and Channel Stability Hydrology Results This example uses the default 25 bins to sort the data, which are displayed in Column D under âBin #â (Figure 5-8). An arithmetic binning process is used in the program to produce equal intervals of discharges represented in each bin. The range for each bin and the associated average discharge is displayed in Columns E through G. Column H shows the frequency or total number of flows from the record that fall into the range for the associated bin. Column I displays the probability density for the flows in each bin. The frequency versus each discharge bin is graphed on the right side of the tab. 5.1.3 Supply Reach Tab The inputs required for the supply reach are entered in the cells that contain red asterisks (see Figure 4-8 for location of asterisks and Figure 5-9 for entered input). The channel dimensions including the bottom width, bank height, bank angle, and floodplain angle are used to create a simplified trapezoidal channel that represents the actual cross section of the channel (see âQuick Reference Guideâ tab). The roughness inputs are Manningâs n values. Only the bank roughness is required for the channel because the roughness of the bed is calculated within the sediment transport calculations. When the inputs have been entered and the âRun Supply Reachâ button pressed, the results for the supply reach will be displayed to the right. Figure 5-7. âStartupâ tab with âStart New Projectâ defined.
CSr tool examples 47 Figure 5-8. âHydrologyâ tab, Big Raccoon Creek example results. Hydrology Columns F and G of Figure 5-9 show a summary of the hydrology results transferred from the âHydrologyâ tab. The discharge is the average for the associated bin range along with the prob- ability of those flows occurring. Hydraulics Columns H through N in Figure 5-9 display the hydraulic characteristics calculated by the program for the associated bin discharge and the simplified trapezoidal channel defined by the inputs. If the depth shown in Column H is less than the bank height specified in the inputs, then Column I will display a âFalseâ and, if it is over the bank height, then âTrueâ will be displayed, showing the program modeled those flows as overbank. Column J is the channel hydraulic radius; Column K is the cross-sectional flow area; and Column L is the associated cross-section averaged flow velocity. Column M is the calculated Manningâs n for the bed of the channel. The Brownlie (1983) roughness equations estimate the roughness by taking into account the form roughness produced by sand-bed forms in the channel associated with the regimes (Upper or Lower) that are displayed in Column N. Sediment Transport Columns O through Q in Figure 5-9 display the sediment transport results for each bin. Col- umn O shows the concentration or estimated sediment yield in parts per million (ppm), which is the direct output from the Brownlie (1981) equation. Column P converts the sediment yield to tons per day. Columns O and P represent the potential sediment yield by the average flow of the associated bin in Column F. Column Q multiplies Column P by Column G, the prob- ability of flows. The result is the âeffectivenessâ or the estimated sediment transported per day by each bin discharge on average in a given year based on the probability of daily flows in the
48 Guidelines for Design hydrology for Stream restoration and Channel Stability flow record. The total effectiveness or total sediment transported per day on average in a given year is the sum of the individual effectiveness for each bin which is displayed at the bottom of Column Q. Underneath these results, the effectiveness is graphed in the bottom left of the tab for each discharge. Supply Reach Geometry In the bottom right, a visual representation of the simplified trapezoidal channel defined by the input dimensions is shown and labeled. The supply reach geometry is on an arbitrary scale, but all dimensions are proportional to each other. This feature is for the userâs reference to get a visual of the geometry used in the calculations. Figure 5-9. âSupply Reachâ tab, Big Raccoon Creek example results.
CSr tool examples 49 5.1.4 Design Reach Tab The required inputs, denoted by red asterisks, are entered for the design reach (Figure 5-10). For this example, the channel dimensions and grain size are assumed to be the same as those of the supply reach. The planform characteristics are optional but are included in this example to show the functionality of this option. The valley slope is required to perform the planform cal- culations. The maximum meander belt width is an optional input that represents the maximum width the valley has to support the channel design laterally. This value should take into account lateral constraints such as a confined valley or infrastructure, etc. If the estimated belt width exceeds this amount, then it will be highlighted in red on the âResultsâ tab. Another optional input is the belt width buffer. This is the total extra room on both sides of the river that can be used as a safety factor of the estimated belt width and/or room for the river to move (see âQuick Reference Guideâ tab for a visual). This amount is added to the calculated belt width. Lastly, the program constraints are defined. This will be the range of widths the program will loop to attempt Figure 5-10. âDesign Reachâ tab, Big Raccoon Creek example inputs.
50 Guidelines for Design hydrology for Stream restoration and Channel Stability to find associated slopes that will produce CSR = 1. The default minimum of 3 ft is used to pro- duce a full family of solutions. The maximum width is set over the supply reach bottom width (usually 1.5 to 2 times) to produce results with widths greater than the supply reach. Pressing the âRun CSR Toolâ button will run the program to find slope and width combinations that balance the sediment capacity of the supply and design reach and produce CSR = 1. This will create a âResultsâ tab and a âDetailed Resultsâ tab. 5.1.5 Results Tab The âResultsâ tab will automatically be selected after the tool is run. This tab will have a sum- mary of the major results for the analysis. The family of stable channel design solutions found by the program with CSR = 1 is graphed at the top left of the tab (Figure 5-11). This is analogous to the output of Copelandâs stable channel design tool in HEC-RAS. Stable Geometries To the right of the plot, the individual stable width and slope combinations are listed in Col- umns N through P of Figure 5-11. Column Q shows the associated CSR for each solution. The solutions are selected because they are within 0.025 of CSR = 1, which will pass the incoming sediment load from the supply reach with minimal degradation or aggradation. In this example, the dimensions and channel characteristics were matched for the supply and design reach to verify the accuracy of the program output. If these characteristics are matched, then the bottom width and slope of the supply reach should be a solution in the family of stable channel design solutions since the same channel could pass the same sediment yield. This can be seen for this example in Figure 5-11. The bottom width for the supply reach is 103.67 ft and the slope is 0.00054. This solution lies between Rows 19 and 20 for the solutions in Columns N through P. Figure 5-11. âResultsâ tab, Big Raccoon Creek example.
CSr tool examples 51 Planform Characteristics The outputs for planform calculations are displayed in Columns R through W in Figure 5-11. Column R is the width versus bankfull depth based on the bank height specified on the design reach tab. The input of the valley slope for the stream allows the program to calculate the sinuos- ity (Column S), the braiding risk (Column T), and the belt width (Column U) for each solution. The estimate for the wavelength based on the 95% confidence interval presented by Soar and Thorne (2001) is displayed in Columns V and W. See âPlanform Characteristicsâ in the CSR Tool Reference Manual (Appendix D of the final report for NCHRP 24-40) and the âQuick Reference Guideâ tab for more information on the planform concepts. Design Reach Geometry A visual of the simplified trapezoidal channel used in the calculations is displayed for the design reach. All dimensions are proportional and labeled except the bottom width. For the design reach, the bottom width varies for each stable solution, so the width is set at an arbitrary length. 5.1.6 Detailed Results Tab In addition to the âResultsâ tab, a âDetailed Resultsâ tab is also created when the CSR analysis is run (Figure 5-12). This tab exhibits more detailed outputs of the analysis per discharge bin Figure 5-12. âDetailed Resultsâ tab, Big Raccoon Creek example.
52 Guidelines for Design hydrology for Stream restoration and Channel Stability for each stable channel solution. Columns B and C of the tab give a summary of the average discharge of each bin used for the supply and design reach calculations and the supply reach effectiveness for each bin. To the right of this summary are the detailed results for each stable channel design solution. The width, slope, and CSR are displayed at the top of each result box. The results report the depth, regime, Manningâs n of the channel bed, and the effectiveness cal- culated for each discharge bin. The lower width solutions are often implausible if the minimum width was chosen for the program constraints, but it allows the program to show the entire family of solutions. These results can show very unrealistic solutions for some bins. The Manningâs n of the bed is labeled as â>0.1â if the roughness goes over this value in an unrealistic situation where the depth is very high for the smallest widths. Below each solution, there are separate boxes that give a summary of the sediment transport percentiles for each solution [see Sediment Percentiles in the CSR Tool Reference Manual (Appen- dix D of the final report for NCHRP 24-40)]. The effective discharge (Qeff) or the discharge bin that moves the most sediment is presented. Also, the discharges corresponding to the percentiles Qs50, Qs75, and Qs90 are linearly interpolated from the effectiveness curve for each solution; these discharges represent the discharges that move 50%, 75%, and 90% of the total sediment yield, respectively. 5.2 Gravel/Cobble Bed This example is for a reach on the Main Fork Red River, Idaho (Figure 5-13). The data used for this example are from surveys done by the U.S. Forest Service for the Rocky Mountain Research Station in Idaho (King et al. 2004). 5.2.1 Startup Tab Figure 5-14 shows the Startup tab that appears when the CSR Tool is first opened. The project information summary is optionally entered in the top right of the tab. Figure 5-13. Main Fork Red River looking down stream from upper end of study reach (King et al. 2004).
CSr tool examples 53 Figure 5-14. âStartupâ tab of the CSR Tool. The stream type is selected as âGravel/Cobbleâ because the D50 for this stream is 20.59 mm, which falls within the âCoarse Gravelâ category in Table 4-1. Also, this is well above the range for the Brownlie (1981) equation, but within the ranges used for Parker (1990) and Wilcock- Crowe (2003) equations (Table 4-2). These ranges are also summarized in the selection guidance window as shown in Figure 5-15. The selection for each field will display the answer chosen below the âSelectâ button. Unlike the âSand Bedâ stream type, there is more than one âTransport Relationshipâ option for the âGravel/Cobbleâ stream type. For this example, the Wilcock-Crowe (2003) equation was selected for the analysis because the amount of sand for the distribution is 10%, which is well outside the range used for the Parker (1990) equation. Since the Parker (1990) equation will not consider sand fractions, this equation was deemed the less accurate choice for the âTransport Relationship.â In addition, the grain size distribution falls mostly within the bounds used to create the Wilcock-Crowe (2003) equation (Table 4-2). The D90 for this example is 55.39 mm and the non-sand distribution range used to produce the Wilcock-Crowe (2003) equation is 2 to 64 mm. These ranges are also summarized in the selection guidance windows for the userâs reference (Figures 5-15 and 5-16). This example reach has discharge data of significant length (35 years) from a U.S. Forest Service gaging station to represent the hydrology of the channel for calculations, so the âFlow Recordâ option was selected for âHydrology Infoâ (Figure 5-17).
54 Guidelines for Design hydrology for Stream restoration and Channel Stability Figure 5-15. Selecting âStream Typeâ on âStartupâ tab. Figure 5-16. Selecting âTransport Relationshipâ on âStartupâ tab. Lastly, âMetricâ is selected as the preferred units for this example (Figure 5-18). This selec- tion will update and format the tabs to accept inputs and produce outputs in this unit of choice. After the preceding four selections are made and the âStart New Projectâ button is pressed, the next required tabs necessary to run the program are displayed in the workbook as shown at the bottom of Figure 5-19.
CSr tool examples 55 Figure 5-17. Selecting âHydrology Infoâ on âStartupâ tab. Figure 5-18. Selecting âPreferred Unitsâ on âStartupâ tab. 5.2.2 Hydrology Tab To follow the steps provided in Section 4.3, the flow record information is first entered, if desired; then just the discharges of the flow record are entered in cubic feet per second (Fig- ure 5-20). Subsequently, the âSort Flow Recordâ button is pressed to produce results. Hydrology Results This example uses the default 25 bins to sort the data displayed in Column D of Figure 5-20 under âBin #.â The resulting total number of bins is 23, because the program found zero- frequency bins and then lowered the bin number from 25 until there were no zero-frequency bins. An arithmetic binning process is used in the program to produce equal intervals of dis- charges represented in each bin. The range for each bin and the associated average discharge is displayed in Columns E through G. Column H shows the frequency or total number of flows from the record that fall into the range for the associated bin. Column I displays the probability density for the flows in each bin. The frequency versus each discharge bin is graphed on the right side of the tab.
Figure 5-19. âStartupâ tab with âStart New Projectâ defined. Figure 5-20. âHydrologyâ tab, Red River example results.
CSr tool examples 57 5.2.3 Grain Size Distribution Tab The âGrain Size Distributionâ tab (Figure 5-21) is displayed and required for this example because it is a âGravel/Cobbleâ bed stream type. The âGrain Size Sample Infoâ is entered at the top left of the tab, if desired. Then, the percentage of bed material that is finer than the grain size class in Column B is entered into Column C of âInputs for Grain Sizeâ for each required field (denoted by red asterisks). Since the Wilcock-Crowe (2003) equation was selected for the analysis, every grain size class has a required input because the sand fraction is considered. When the inputs have been entered and the âRun Grain Sizeâ button pressed, the distribution is analyzed to produce the necessary parameters to run the program. Outputs are displayed under âDistribution Summary (mm),â and the â% Finerâ versus grain size class is plotted in the graph in the lower right corner. Distribution Summary The results of the analysis are presented in âDistribution Summary (mm)â of the âGrain Size Distributionâ tab (Figure 5-21). Rows 5 and 6 show the geometric mean grain diameter (Dg) and Figure 5-21. âGrain Size Distributionâ tab, Red River example results.
58 Guidelines for Design hydrology for Stream restoration and Channel Stability the geometric standard deviation (sg); Row 7 shows the sand fraction, which in this example is 0.1 or 10%. Rows 8 through 13 show common grain size percentiles representing the particle diameter for which 16%, 30%, 50%, 70%, 84%, and 90% of all sediment in the distribution is smaller. Equation Boundaries Reference The ranges presented by Parker (1990) and Wilcock and Crowe (2003) to develop the equations, as shown in Table 4-2 of this document, are summarized again for reference under âEquation Boundaries Reference.â This can be used to help check if the transport equation selected for the analysis is the most desired choice. 5.2.4 Supply Reach Tab The inputs required for the supply reach are entered in the cells that contain red asterisks (inputs for the example are in red in Figure 5-22). The channel dimensions including the bottom width, bank height, bank angle, and floodplain angle are used to create a simplified trapezoidal channel that represents the actual cross section of the channel (see the âQuick Reference Guideâ tab). The roughness inputs are Manningâs n values. Only the bank roughness is required for the channel because the roughness of the bed is calculated within the sediment transport calculations. When the inputs have been entered and the âRun Supply Reachâ button pressed, the results for the supply reach will be displayed to the right (Figure 5-22). For this example, a trapezoid was fit to the actual cross-sectional data of the channel in order to estimate the dimensions entered for the supply reach as shown in Figure 5-23. From the data points, the bottom width is estimated as 7.6 m, the bank height as 0.84 m, bank angle 2:1 (note the figure axes are not proportional), and the floodplain angle as 20:1. The bed slope used for the calculations was estimated from the longitudinal bed profile of the stream as seen in Figure 5-24. Hydrology Columns F and G in Figure 5-22 show a summary of the hydrology results transferred from the âHydrologyâ tab. The discharge is the average for the associated bin range along with the prob- ability of those flows occurring. Hydraulics Columns H through N display the hydraulic characteristics calculated by the program for the associated bin discharge and the simplified trapezoidal channel defined by the inputs. If the depth shown in Column H is less than the bank height specified in the inputs, then Column I will display a âFalse,â and if it is over then âTrueâ will be displayed showing the program modeled those flows as overbank. Column J is the channel hydraulic radius, Column K is the cross-sectional flow area, and Column L is the associated cross-section averaged flow velocity. Column M is the calculated Manningâs n for the bed of the channel. The roughness of the bed is calculated using Limerinos (1970) equation for gravel/cobble-bed stream types. Column N displays the dimension- less shear stress of the bed or the Shieldsâ stress based on the surface geometric grain size. Sediment Transport Columns O through Q in Figure 5-22 display the sediment transport results for each bin. Column O shows the estimated sediment discharge in kilograms per second from the bedload transport equation. Column P converts this value to a sediment yield in tons per day, which represents the potential sediment yield produced by the average flow of the associated bin in Column F. Column Q multiplies Column P by Column G, the probability of flows. The result is
CSr tool examples 59 Figure 5-22. âSupply Reachâ tab, Red River example results. Figure 5-23. Fitted trapezoid cross section for supply reach of Red River from actual survey (King et al. 2004).
60 Guidelines for Design hydrology for Stream restoration and Channel Stability the âeffectivenessâ or the estimated sediment transported per day by each bin discharge on aver- age in a given year based on the probability of daily flows in the flow record. The total effective- ness or total sediment transported per day on average in a given year is the sum of the individual effectiveness for each bin which is displayed at the bottom of Column Q. Underneath these results, the effectiveness is graphed in the bottom left of the tab for each discharge. Supply Reach Geometry In the bottom right of Figure 5-22, a visual representation of the simplified trapezoidal chan- nel defined by the input dimensions is shown and labeled. The supply reach geometry is on an arbitrary scale, but all dimensions are proportional to each other. This feature is for the userâs reference to get a visual of the geometry used in the calculations. 5.2.5 Design Reach Tab Figure 5-25 shows the entered inputs required for the design reach (in red). For this example, the channel dimensions and grain size are assumed to be the same as the supply reach. The plan- form characteristics are optional but are included in this example to show the functionality of this option. The valley slope is required to perform the planform calculations. The maximum meander belt width is an optional input that represents the maximum width the valley has to sup- port the channel design laterally. This value should take into account lateral constraints such as a confined valley, or infrastructure, etc. If the estimated belt width exceeds this amount, then it will be highlighted in red on the âResultsâ tab. Another optional input is the belt width buffer. This is the total extra room on both sides of the river that can be used as a safety factor of the estimated belt width and/or room for the river to move (see âQuick Reference Guideâ tab for a visual). This amount is added to the calculated belt width. Lastly, the program constraints are defined. This will be the range of widths the program will loop to attempt to find associated slopes that will produce CSR = 1. The default minimum of 1 m is used to produce a full family of solutions. The maximum width is set over the supply reach bottom width (usually 1.5 to 2 times) to produce results with widths greater than the supply reach. Pressing the âRun CSR Toolâ button will run the program Figure 5-24. Red River longitudinal bed profile with fitted trend line to find bed slope (King et al. 2004).
CSr tool examples 61 to find slope and width combinations that balance the sediment capacity of the supply and design reach and produce CSR = 1. This will create a âResultsâ tab and a âDetailed Resultsâ tab. 5.2.6 Results Tab The âResultsâ tab (Figure 5-26) will automatically be selected after the tool is run. This tab will have a summary of the major results for the analysis. The family of stable channel design solu- tions found by the program with CSR = 1 is graphed at the top left of the tab. This is analogous to the output of Copelandâs stable channel design tool in HEC-RAS. Stable Geometries To the right of the plot in Figure 5-26, the individual stable width and slope combinations are listed in Columns N through P. Column Q shows the associated CSR for each solution. The solutions are selected because they are within 0.025 of CSR = 1, which will pass the incoming sediment load from the supply reach with minimal degradation or aggradation. In this example, Figure 5-25. âDesign Reachâ tab, Red River example inputs.
62 Guidelines for Design hydrology for Stream restoration and Channel Stability the dimensions and channel characteristics were matched for the supply and design reach to verify the accuracy of the program output. If these characteristics are matched, then the bottom width and slope of the supply reach should be a solution in the family of stable channel design solutions because the same channel could pass the same sediment yield. This can be seen for this example in Figure 5-26. The bottom width for the supply reach is 7.6 m and the slope is 0.006. This solution lies between Rows 11 and 12 for the solutions in Columns N through P. Planform Characteristics The outputs for planform calculations are displayed in Columns R through W in Figure 5-26. Column R is the width versus bankfull depth based on the bank height specified on the âDesign Reachâ tab. The input of the valley slope for the stream allows the program to cal- culate the sinuosity (Column S), the braiding risk (Column T), and the belt width (Column U) for each solution. The calculated belt widths in Rows 13 through 18 are in red because the estimated belt width plus buffer is larger than the maximum meander belt width that was specified in the âDesign Reachâ inputs. The estimate for the wavelength based on the 95% confidence interval presented by Soar and Thorne (2001) is displayed in Columns V and W. See âPlanform Characteristicsâ in the CSR Tool Reference Manual (Appendix D of the final report on NCHRP 24-40) and the âQuick Reference Guideâ tab for more information on the planform concepts. Design Reach Geometry Similar to the supply reach, a visual of the simplified trapezoidal channel used in the calcula- tions is displayed for the design reach. For the design reach, the bottom width varies for each stable solution, so the width is set at an arbitrary length. Figure 5-26. âResultsâ tab, Red River example.
CSr tool examples 63 5.2.7 Detailed Results Tab In addition to the âResultsâ tab, a âDetailed Resultsâ tab (Figure 5-27) is created when the CSR analysis is run. This tab exhibits more detailed outputs of the analysis per discharge bin for each stable channel solution. Columns B and C of the tab give a summary of the average discharge of each bin used for the supply and design reach calculations and the supply reach effectiveness for each bin. To the right of this summary are the detailed results for each stable channel design solution. The width, slope, and CSR are displayed at the top of each result box. The results report the depth, dimensionless shear stress (t*), Manningâs n of the channel bed, and the effectiveness calculated for each discharge bin. Below each solution, there are separate boxes that give a summary of the sediment transport percentiles for each solution [see âSediment Percentilesâ in the CSR Tool Reference Manual (Appendix D of the final report on NCHRP 24-40)]. The effective discharge (Qeff) or the dis- charge bin that moves the most sediment is presented. Also, the discharges corresponding to the percentiles Qs50, Qs75, and Qs90 are linearly interpolated from the effectiveness curve for each solution. These discharges represent the discharges that move 50%, 75%, and 90% of the total sediment yield, respectively. Figure 5-27. âDetailed Resultsâ tab, Red River example.