3 Table of Contents. Introduction. Installing and Activating... 8 Getting Updates Basic Working Procedures

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1 User's Guide

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3 3 Table of Contents 1. Introduction Installing and Activating Getting Updates What To Do First Starting a New Project Setting Up Your Model Adding River Reaches Adding Cross-Sections Adding Cross-Section Data Reach Lengths Geometric Data Optional Features Bank Stations and n-values Setting Section Centerline Starting Tailwater Setting Flow Rates Performing Steady Flow Calculations Supercritical Profiles Viewing Results Cross-Section Plots Water Surface Profiles Plan Drawings Tabulated Results Printing Results Working With Bridges Adding Bridge Sections Working With Culverts Adding Culvert Sections Working With Inline Weirs Adding Weir Sections Ineffective Flow Areas Adding a Background Map Custom Labels Project Settings Saving and Retrieving Project Files Modeling Best Practices... 74

4 4 Table of Contents 3. Computational Methods Channels Friction Losses Expansion Contraction Losses Computation Procedure Supercritical Flow Profiles Bridges Culverts Outlet Control Inlet Control Inline Weirs Supercritical Flow Manning's n Values End User License Agreement (EULA) 104 Index 107

5 Introduction

6 6 Introduction 1 Introduction Welcome and congratulations for choosing the industry's most easy-to-use open channel modeling software. This state-of-the-art desktop application features comprehensive open channel modeling utilizing "tried and true", industry-accepted computational methods. All while wrapped behind a rich user interface, built from the ground up with Dot-net, Windows Presentation Foundation. Say goodbye to those outdated forms based programs! If you have landed on this page from an internet search and would like to visit our website, please visit What is? was developed primarily for practicing civil engineers and related professionals involved with urban and rural storm drain modeling and design. More specifically, for calculating and producing steady flow water surface profiles for open channels. was designed specifically to be an easy-to-use alternative to today's bloated public-domain programs, such as HEC-RAS and WSPRO for performing day-to-day hydraulic analysis on open channel systems. Channel studio is not a data wrapper or a pretty user interface on top of HECRAS or any other freeware-type software. This product is all-inclusive, purpose built from the ground-up and needs no other software to run. No importing and exporting! It uses well-known methodologies, including those developed by the U.S. Army Corps of Engineers - Hydrologic Engineering Center (HEC) and the Federal Highway Administration (FHWA). It is assumed throughout this manual that the user has a basic understanding of open channel hydraulics. What you can do with Perform one-dimensional, steady flow, hydraulic analysis on a system of natural or constructed channels. Model channels containing bridge sections including vertical or sloped abutments and piers. Model channels with multi-barreled culverts with circular, rectangular, elliptical and arch shapes. Model channels with inline overflow weirs. Model a variety of open channel sections including trapezoidal and userdefined with varying roughness.

7 Introduction 7 Draw and create realistic river reaches on your model as curves or straight lines. Produce flood plain maps and export to cad files. Produce professional looking, agency-ready tabulated reports, graphs, plans and profiles. Work in U.S. Customary or Metric units. Much more! Technical Highlights Channels Computes water surface profiles using standard energy-based methods. Calculation options include a variety of friction-loss methods including Ave Conveyance, Ave Friction Slope and Geometric Mean. Compute using up to three unique user-defined flow profiles, each with varying Qs. Up to 250 user-defined points can be used to describe User-defined channel sections. N-values can vary across sections via Left and Right Overbank Stations. Computes supercritical flow profiles with hydraulic jumps. Specify any known tailwater elevation, normal depth or critical depth as a starting control point. Automatically constructs and includes ineffective flow areas upstream and downstream of bridge and culvert sections. Allows you to graphically draw ineffective flow areas for any cross-section. Reverse cross-section data from looking upstream to downstream. Copy and paste geometric data from other cross-sections to minimize user input. Interpolate cross-section data between any two sections for easy section insertion. Adjust geometric cross-section data up or down with a single input. Culverts Computes hydraulic grade line (HGL) with flow regimes including supercritical flow and hydraulic jumps. Models inlet and outlet control flow regimes. Computes roadway/embankment overtopping flows. Uses FHWA - HDS-5 methodology. Handles partial, full and surcharged flow regimes automatically. Models circular, rectangular, arch and arch-open bottom sections. Bridges

8 Introduction 8 Computes hydraulic grade line (HGL) through bridge crossings. Specify high and low chord elevations, left and right abutments and multiple vertical piers. Computes roadway overtopping flows. Inline Weirs Computes hydraulic grade line (HGL) over inline weir structures. Weirs can represent emergency spillways or overflow structures. Output Features Colorful, professional reports are easy to read and interpret. Coordinate-based Plan, Section and Profile plots for easy floodplain delineation. Tabulated reports are exportable to.txt or.csv file formats. Finished Plan Views can be exported to.dxf files or a variety of image formats. Print Preview. 1.1 Installing and Activating By now you probably have installed but just in case you haven't, just follow the purchase/download instructions at the product's website The initial download will contain the free trial version which has no time limit but limited functionality. For example, you won't be able to save project files; most of the reports will be watermarked and projects will be limited to 5 cross-sections. uses Microsoft's "Click-once" technology which makes the installation process fast and easy. An icon will be automatically added to your desktop and will launch the program. Trial version users will be greeted with a sample project file to help them get acquainted. How to Activate Culvert Studio Upon launch, the program checks for the registration serial number. If it is not available, an activation screen appears like the following:

9 Introduction 9 Once the serial number is entered it is stored and you won't be reminded again. Loose your serial number? If for some reason your serial number is lost, please support@hydrologystudio.com for retrieval. 1.2 Getting Updates will automatically check for program updates, revisions and fixes upon each launch. You may choose to "Update" then or "Skip" and wait until a later time. If you choose to skip the update, you will not be prompted again until the next update is released. Thus it is highly recommended you click Ok. If an update is available, you'll see a screen like this:

10 Introduction 10 Click [Ok] to immediately download the update. You may then see the following screen: If so, click the "More info..." link and then click [Run anyway]. It will take about 5 to 10 seconds to download and your new program will launch.

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12 12 2 This section describes the most common, basic tasks you will use when working with Culvert Studio. It is designed as a "How-To" guide and reference manual. Although it is organized roughly in the order that you would perform the tasks you don't need to start at the beginning and work your way through. Every topic contains comprehensive links to background information and other relevant subjects so you can just pick out the task you need to perform and begin. was designed to be easy to use while performing hydraulic analysis on most any open channel system which can include natural or manmade channel sections, bridges and culverts. The user-interface was designed to minimize inputs, dialog boxes and put everything right in front of you. Below is the opening screen with an existing project Loaded. Your screen will look just like this one except yours will be blank. Primary Working Tabs In the upper left you'll see four tabs from which you'll use to setup, manipulate and compute your channel model. Model You'll use this tab when starting a new project. Here you will draw your river

13 13 reaches, add, insert and remove cross-sections along those reaches, import background maps and more. X-Sections The X-Sections tab displays cross-sections and allows you to graphically manipulate them. Profile Automatically displays a profile of your model. Plan Automatically draws a coordinate-based plan view of your model. Reports Shows screen examples of your printed reports. Print-preview is also available during printing. To the right you'll find a second set of tabs used primarily for inputting crosssection and flow data. Any of these tabs can be viewed while working on the primary tabs described above. Section Data This displays an input grid you'll use to enter geometric data to describe the channel sections. Flow Data Here you'll enter flow rates for each cross-sections, up to three user-defined profiles, 5-year, 50-year and 100-year, for example. Results A separate tab is used for displaying computed results for each individual section. What makes so easy to use is that you can view any combination of these tabs while computing your water surface profiles. 2.1 What To Do First 1. Create a folder on your computer to hold your project files uses Microsoft's "Click-Once" technology to install itself on your computer. As you may have noticed, it was very fast and easy. While it's

14 14 void of confusing options, it does not create file folders for your projects. It is recommended you create a folder to hold these. For example the following folder configuration is recommended under your Documents folder: See, "Saving and Retrieving Project Files " for more information. Starting a New Project Starting new project with is as easy as creating a new spreadsheet file you just click on the File menu, select New Project. That's it. In fact, the program is ready to start a new project upon initial launch. If you plan to change the current system units, you must change them prior to the start or opening of a new project. Choose U.S. Customary or Metric. See, "Project Settings 71 " for more information. 2.3 Setting Up Your Model will model open channels with any shape of channel section including predefined and user-defined. It can model up to 100 river reaches

15 15 with up to 100 cross-sections. Each cross-section can be described with up to 100 station, elevation points and can be a "Channel", "Bridge", "Culvert" or "Weir" section. You can also add a background Map from either an image file or DFX file. The software has many built-in functions to make computing water surface profiles as easy as Here are the basic steps to developing your model: 1. Draw in your river reaches on the Model tab... in the upstream direction. 2. Place cross-sections along the river reach starting at the most downstream reach, Sta Enter the geometric data for each cross-section as looking upstream. 4. Enter the flow data (Qs) for the cross-sections. 5. Compute. 6. Look at the results. You'll have lots to see including plans, profiles, sections and tabulated reports. You'll find this surprisingly easy to do! The remainder of this chapter will describe each of these steps in detail. English or Metric? Before you begin entering any data, you should specify the units you'll be working in, i.e., U.S. Customary or Metric. This is done by clicking on the Project button on the top Ribbon Menu and choosing your units. Once this is done, the units will remain for subsequent projects until changed Adding River Reaches The first step in building your model is drawing in the river reaches. These reaches will ultimately contain cross-sections, placed along its centerline, describing the actual channel and overbanks. Your river reaches can consist of multiple segments, up to 100, and are X, Y coordinate based. A background map 68 can also be loaded to draw against if desired. The real-world coordinates of your mouse pointer is always shown on the far left of the status bar at the bottom of your screen. Setting the Drawing Canvas Scale The drawing canvas opens up with preset X, Y (N, E) extents. The origin is at the lower left corner of the canvas and is set to 100 ft, 100 ft (10 m, 10 m). The X extent is 1,100 ft (510 m). The Y extent is computed based on your computer's display aspect ratio. The canvas extents can be adjusted at any

16 16 time by clicking the map button on the side toolbar and selecting, "Set Background Extents" from the Map menu shown here: See "Adding a Background Map coordinates. 68 " for more information on setting the map How to Add Reaches Channel reaches are drawn by dragging your mouse, starting at the most downstream point and working upstream. Each reach segment can be either curved or straight to match the actual channel or flood plain. The most downstream reach must be straight. Here's how to do it Step-by-Step: 1. On the Model tab, click on the River Reach button on the side tool bar. 2. Move your mouse pointer over to the drawing canvas and place it at the starting point, most downstream end. 3. Drag your mouse to the upstream end of this reach and release the mouse button. The reach number, length and centerline station will be displayed on the status bar at the bottom of your screen while drawing. 4. Repeat Step 3 for additional reaches until you're finished drawing all of the them. Just start at the upstream end of the most upstream reach. The program will display a red circle there and will automatically snap to it. 5. When finished, click the Ok/Select button on the top of the side tool bar or press the [Escape] key. Below is an example of a typical river reach with six segments.

17 17 Rules, Options & Tips All reach segments are assumed to be curved, except Reach No. 1. It's always straight. Reach segments can be of any length. Use your mouse wheel to zoom in/ out or contract/expand the coordinates. Drag your mouse over the white space to Pan. will automatically draw circular curved segments. To insure smoothness, it uses the downstream reach as the Point of Curvature, PC, and the mouse position as the Point Tangent, PT. It will also draw dotted tangent lines for your reference while drawing. You can force straight-line segments by holding down the [Shift] key while dragging. The program uses circular curve formulas for calculating reach segment lengths, and bezier curves for drawing. Try to keep the deflection angle below 90 degrees. The dotted lines will turn red once this angle has exceeded 90 degrees. When Modeling a Simple Channel

18 18 If drawing against a map and you want to follow a narrow channel, keep the leading dotted line within the actual channel boundaries on the map. Use the leading dotted line as a guide for the next upstream reach. Correct. Keep the leading dotted line within the actual channel boundary. Incorrect. Leading dotted outside the upstream channel. When Modeling a Floodplain Modeling entire floodways is easy. Just draw your reach along the center of the floodplain limits as shown here:

19 19 Draw reaches along the centerline of your floodway Your reaches do not need to follow the exact route of the "Channel" boundary. Remember, you can input reach lengths for the Left and Right Overbanks and Channel separately in the section geometry. The river reaches are just placeholders for your cross-sections. At the time of this writing, does not allow tributary river reaches. Only one contiguous river system. You can add more reach segments at any time. Just snap on to the most upstream reach and draw as described above. To edit an existing reach, double-click on the reach and then drag the upstream end of the reach to its new position. The upstream connecting reach, if one exists, will automatically adjust to maintain tangent lines. You may delete reach segments by selecting them with you mouse (click anywhere on the segment) an clicking the trash button on the side tool bar. Only the most upstream reach can be deleted. Use the Reach Width slider bar on the Ribbon Menu to change the drawing width of the reach. This is cosmetic only but is helpful setting the drawing canvas scale to match the map scale. Actual channel widths will be derived from the channel cross-section geometry.

20 20 Adding a Background Map You can also add a coordinate-based background picture to draw against. The program supports image file formats as well as DXF. See "Adding a Background Map 68 " for more information Adding Cross-Sections Once you have added the river reaches to your model, you can add the associated cross-sections. Again, we add these in sequential order starting at the downstream end working upstream. Sections should be added at locations where there are any significant changes in the section shape, geometry or channel slope. Also, automatically prepares a coordinate-based Plan map of your Model. See Plan Drawings 43 for additional information. How to Add Cross-Sections 1. From the Model tab, click on the Cross-Section button on the side tool bar. 2. Move the mouse cursor over to the first river river reach. Channel studio will automatically draw a section line perpendicular to the reach segment. When you have located the section at the desired river station, click your mouse button. A new section will be added and numbered accordingly. Repeat this process for additional sections. Note: You will have the ability to directly edit the section station location after placement on the Input Grid. See Adding Cross-section Data 23.

21 21 Adding a new sections It is not necessary for your cross-sections to coincide with river reach connection points. In fact, you should avoid placing them directly over them as shown above. 3. Click the Ok/Select button on the side tool bar or press the [Escape] key when done. Rules, Options & Tips Use the Slider bars on the Ribbon Menu to increase or decrease the section line lengths and number labels. This helps to provide a suitable scale to match the canvas coordinates. Cosmetic only. This has no affect on the actual channel section widths. Use the Station Increment setting to automatically snap the section locations

22 22 to pre-defined stations. For example, to easily add sections every 100 feet, select 100. The default is 1 ft (m). Sections can be added or inserted in any order at any time. Channel Studio will take care of the numbering. For convenience, will automatically calculate the initial reach lengths between sections based on the river reach stationing. However, you will have the option to override these values when inputting the actual cross-section geometric data. For example, the reach lengths of left and right overbanks and channel. To move an existing section upstream or downstream, double-click the section line or label circle. Then drag the section to the new location. Your mouse cursor will not need to be exactly on the label to move. In fact, it's easier if the cross-hair is just above the label. Click the [Ok/Select] button when finished editing. Delete any cross-section by first selecting the Section Line and clicking the Trash button. Only one section can be deleted at any time. A typical model layout with cross-sections looks like this:

23 23 Typical model layout with cross-sections at the right places Below is an example using a coordinate-referenced background map. Model of flood plain with reaches and sections Adding Cross-Section Data Once your river model is complete, you are ready to add data for each of the cross-sections. Each input item is described below. To add section data, first click the X-Sections tab as shown below. Sections can be selected by clicking on the Section List to the left. Once selected, the data grid on the right side of your screen will populate with the current data.

24 24 To enter data, type in the value or select from a drop-down input box, and press [Enter] or the [Tab] key. Once the data is input, click [Apply]. Repeat these steps for each section. Use the [< Prev] and [Next >] buttons to navigate downstream to upstream. Data is divided into categories: Reach Lengths 25 Channel Section Geometric Data Manning's n-values 32 Bank Stations 32 Coefficients Tailwater 35 (Section 1 only) 26 While entering data for the first time, the canvas will automatically display help diagrams to assist in your data entry. River Station The initial River Station is always set from the Model view when you first add your sections. However, you can directly edit this on the input grid for better specificity if needed. Section Name Optional but it is a recommended input. Enter any alphanumeric name.

25 Reach Lengths There are three unique reach lengths you can enter. One for the Left and Right Overbanks and one for the Channel portion of each section. These reach lengths are separate from the River Station and should refer to the actual distance the water travels along their respective paths. These paths are indicated by your stationing inputs for the Left and Right Overbank Stations described later. For example, the image below shows a channel with Left Overbank, Channel and Right Overbank. While these distances are the same between Sections 1 & 2, they vary between Sections 2 & 3 because the channel is curved. The Left Overbank distance is longer than the Channel. The Channel Reach length is longer than the Right Overbank reach length. In some cases, the Channel portion may meander, causing the Channel Reach to be the greatest. Initially, the program automatically enters equal reach lengths based on the Station difference between sections when you add sections to the model. These are the defaults. It is here that you can override that. Note that if you return to the Model tab and edit the locations of the sections, the program will again enter default reach lengths and you'll need to make any necessary adjustments. For most uniformly-shaped cross-sections, the defaults will suffice. Reach lengths are not required for Section 1 and the category will be collapsed.

26 26 If you edit the locations of a section, the reach lengths will adjust according to the river stationing Geometric Data Channel sections are described by specifying X, Y or Station, Elevation points from left to right looking upstream. Up to 250 points can be entered for each section. allows you to quickly input predefined sections, i.e., Trapezoidal, Triangular or Rectangular as well as User-Defined sections. Other options allow you to: Copy geometric data from one section and paste into another Copy the section data from the previous section Generate section data by interpolating between any two sections Horizontally flip cross-section data to convert sections looking downstream to looking upstream Add elevation adjustments (up or down) to a cross-section Graphically set the Overbank Stationing Graphically add ineffective flow areas Section Type Choose your section type, Trapezoidal or User-Defined, from the drop-down list box. Each are described below.

27 27 Trapezoidal Using the Trapezoidal type you can quickly add triangular, rectangular or trapezoidal shapes with varying side slopes. Bottom Width Enter the bottom width of the channel. For a triangular section, enter zero. Side Slope Left & Right (z:1) Enter the left and right side slopes, z horizontal to 1 vertical, for the channel. Enter zero for rectangular shapes. Total Depth Enter the total depth to be analyzed for this section. Invert Elevation Enter the invert elevation of this section. This item will be automatically computed when using User-defined sections. Once you have defined a Trapezoidal section, you can later select "UserDefined" as the section type. The program will automatically import the X, Y coordinates for this section for further modification and will convert it to a User-Defined shape. User-Defined You can enter up to 250 unique Station, Elevation points to describe a channel section. Stationing should begin at zero.

28 28 User-defined channel section To use this channel feature, select User-defined as the Section Type from the drop-down list. Next click the [Define] button to open the User Defined Channel screen. Example user-defined cross-section A user-defined section is described by entering points containing offset stations, elevations. Station

29 29 Enter the station for this point in feet or meters from the leftmost side. This is the distance from a zero baseline. If you are pasting or entering data that does not start at zero, that's okay. will adjust them by zeroing-out the data after clicking [Ok]. Elevation Enter the corresponding elevation for this point. Click [Ok] when done. Inserting and Deleting Rows You can insert and delete rows by selecting a row and right-clicking. Copy and Paste Data Similarly, you can copy the entire grid to the Windows Clipboard as well as paste previously copied data, for example, from a spreadsheet Optional Features has some built-in features that will save you time when entering in cross-section data. The features include the ability to: Copy geometric data from one section and paste into another Copy the section data from the previous section Generate section data by interpolating between any two sections To perform one of these tasks, simply right-click on section located on the Section List to the left of the X-Section screen. The following menu pops up.

30 30 Copy Previous Section Geometry This selection will copy and paste the section geometry including Bank Stations from the section just downstream. Copy Section Geometry This copies the current section's geometry so that it can be used on any other section. Paste Section Geometry This will paste geometry that was Copied. Clear This Section This will clear only the section geometry. It will not permanently remove the section from the project. Interpolate This feature will create new geometry for this section by interpolating between the downstream section and the upstream one. It uses a sophisticated string methodology as shown in the image below. It basically creates a section which contains coordinates from both up and down stream sections. It connects the first and last coordinates as well as the bank stations. Then linearly interpolates between the two to develop elevations. The new, interpolated cross-section will contain X, Y points that are common to both up and downstream sections.

31 31 Cross-section interpolation Other options are available via controls located at the top of your X-Sections plot. Adjusting Section Elevations If you have copied geometric data from another section, you may have a need to raise or lower the cross-section in order to account for any channel slope. Another situation may arise when you are designing channel sections and need to make adjustments to the channel. This feature allows you to enter a value (positive or negative) that will be algebraically added to each elevation across the section.

32 32 Adding an adjustment to all section elevations To adjust, enter the amount in feet (meters) and click the [Enter] button next to the input box. A dotted line indicating the position of the new section will be overlayed. To accept, click [Apply] on the Channel Section Input grid. Reverse Section Data If you have entered or pasted geometric data that is looking downstream rather than up, you can easily reverse it by clicking this button Bank Stations and n-values can divide cross-sections into three unique parts: Left Overbank, Channel and Right Overbank. You can specify unique roughness coefficients for each as well as the offset stations that locate them along the cross-section.

33 33 Example section with overbank stations at 200 and 230 Bank Stations are optional and are only used to indicate the areas corresponding to the n-values for the Left Overbank, Channel and Right Overbank. Please note that bank stations must coincide with an existing X, Y point describing the channel section. In the section shown above, the Left Overbank area is between Sta 0 and 200. The Channel portion is between 200 and 230. The Right Overbank is from 230 to 430. Setting Bank Stations Graphically Overbank stations can be directly entered into the input grid or can be placed graphically by using the LOB and ROB controls at the top the X-Section Plot. Just click on the arrows to move the bank stations as needed. Setting n-values Enter the Manning's n-values corresponding to the Overbanks and Channel portions of the section. A table of suggested values can be found here Setting Section Centerline Depending on the station and elevation points entered, there may be times you'll want to reset the centerline of your channel section. This centerline station is used by the Plan view tab to position the cross-section relative to the centerline of the river reach.

34 34 This feature has no affect on water surface profile calculations. When entering your section for the first time, or after editing your section's station / elevation data, the program attempts to set the centerline station by locating the channel invert. However, if more than one elevation share this invert, it will be set to the first one as shown below. Check CL to On to view the centerline station. Just move the section line to reset. To reset, be sure the CL check box in the upper right is checked. Then move the highlighted section to the new position. No need to click [Apply].

35 35 Centerline reset Starting Tailwater Needed only for Section 1, the most downstream section, the Tailwater Elevation sets the water surface elevation where calculations begin. You have the following options but please note that if any Tailwater Elevation is below critical depth, will reset it to critical depth. Normal Depth Recommended if no known elevation exists and there is positive channel slope. This will compute Normal depth as per manning's equation. It uses the n-value from the Channel section only. The Slope is calculated based on the Channel Reach Length. Note that there must be a positive slope between Section 2 and Section 1. Critical Depth This option is not typically recommended but will begin calculations at critical depth, minimum specific energy. Known Elevation Choose this option to specify known starting tailwater elevations. You can enter a unique elevation for each flow profile.

36 36 Known tailwater elevation at 105 ft Setting Flow Rates Once you have developed the layout and entered geometric data for your model, you can specify flow rates. You have the ability to specify a unique flow rate for each cross-section. In addition, you can add up to three sets of flow profiles. Unique names can also be assigned to these profiles for clarity in the reports. Cross-sections must first exist before assigning flow rates. To enter flows, click on the Flow Data tab at the top of the Input Grid to the right of your screen.

37 37 This table contains a listing of all available cross-sections, their River Stations and three separate columns for flow rates. Type in the flow rate for the first section and press the [Tab] key. The input box will drop down to the next section and will use the previous flow rate as the default input, saving you from having to retype the same value. Flow rates may vary from one section to the next. Apply Values When finished, click the [Apply] button to accept. Clear Values If you need to make adjustments to an entire column of Qs, sometimes it's best to clear out the column first and take advantage of the auto-default feature. To clear the flow inputs for any particular profiles, first click on any profile column on the table and then click the [Clear] button. Profile Names You may assign unique names for the profiles in the Project Settings 71. The names will appear on all output but will stay labeled as Prof 1, Prof 2 and Prof 3 on this input screen. 2.4 Performing Steady Flow Calculations After setting up your model, it's time to compute some results. Computing profiles is very easy with. It goes through great lengths to insure the integrity of your input data. If something is out of order, it will alert you immediately. But at this point, it might be a good time to save your your project file, especially if you have a lot of cross-sections with a lot of data. You can compute profiles at any time and from any of the major tabs, i.e., Model, X-Sections, Profile, Plan or Results. To compute, click on the 'Compute" tab on the top Ribbon Menu and click [Run]. Depending on which tab you are viewing, you will see immediate results. Calculation Options Here are a few options you'll have when computing.

38 38 Discharge Profile Please choose one of the three profiles. These correspond to the flow rates that were entered earlier in the Flow Data tab as well as the Starting Tailwater elevations. Friction Loss Options will use up to three methodologies for computing friction losses. Any of these methods will give satisfactory results as long as your reach lengths aren't too long. Average Conveyance Average Friction Slope Geometric Mean The Average Conveyance is known to provide the best overall results and is the default method used in as well as other well known programs such as HEC-RAS. If you're struggling to get satisfactory results with one method feel free to try the others. But the biggest reason why models fail is due to inadequate number of cross-sections or too large of a change in conveyance or velocity head from one section to the next. Conveyance should not change by more than about 30% and velocity head should not change by more than 1 foot. Here are some best practices 74 to guide you Supercritical Profiles Compute Supercritical Option This option can be turned on or off on the top Ribbon Menu. It is recommended to be turned on, but keep in mind, that most natural channels flow in a subcritical regime. Turned Off If cannot balance the energy equation within a low tolerance, it

39 39 assumes critical depth and moves upstream, regardless if this option is on or off. If this occurs, you should first investigate why. As mentioned above, a nosolution may be due to inadequate number of cross-sections or too large of change >30% of conveyance between sections. Supercritical Flow OFF Turned On If this option is turned on, when the calculations reach the very upstream end, the software turns around and checks for any sections that were left (assumed) at critical depth. It begins at the first one and computes a supercritical profile in the downstream direction. It computes this profile until it cannot find a supercritical solution. It is between these two sections where an hydraulic jump may occur. Supercritical Flow ON Jump Location

40 40 In general, hydraulic jumps are difficult to locate on natural channels. Using concepts of momentum or Specific Force, the program attempts to determine if in fact a jump is in place. If so, you will see it on the profiles as shown above. If not, it will provide a message. Notice in the profile plot above the energy grade line (EGL) dips up after the jump. It should dip down indicating a loss of energy, not a gain. This is a telltale sign that the jump probably occurs further upstream. The best way to locate a jump is to insert an addition sections. For example, in the profile shown above, it's assumed the jump is located somewhere between Sections 2 and 3. By inserting an interpolating a new section between 2 and 3, we might better locate it. By inserting a new section, we are able to calculate a more precise location 2.5 Viewing Results Once the calculations are complete, you'll be rewarded with many different ways to view your results: Cross-Sections 41 Profile Plots 42 Plan Drawings 43 Tabulated Reports 44

41 Cross-Section Plots If the computed results are current with inputs, you'll get a plot similar to the one shown below on the X-Sections tab.. Notice how the Legend indicates the flow profile name. In this case, "100-year" These graphs are self-explanatory. You can utilize the options in the upper right of the plot for the following: EGL This draws the Energy Grade Line (Water Surface + Velocity ^2/2g) when turn on. Persistent Scale When checked on, this will use a single X, Y scale for all cross-sections. Note that if you have any cross-sections void of their geometric data, you will see a blank screen. Either turn this function off or add the remaining data. Getting a Hard Copy You can instantly export this graph as an image file for insertion into other documents by right-clicking anywhere on the plot and choosing, "Export this Chart...". Of course, a more formal presentation is available by clicking on the [Print] button on the top Ribbon Menu, Home tab. See Printing Results 45 for more information.

42 Water Surface Profiles The Water Surface Profile plot provides a longitudinal cross-sectional view of the river system from downstream to upstream. You may specify a range of sections to include or opt to plot "All." To view this, click the Profile tab. Profile Plots are great at showing the big picture By utilizing the check box options in the upper right, you can turn on or off the: Cross-section location lines Overbank lines Water surface Energy Grade Line (EGL) Critical Depth line Set the Starting and Ending sections on the plot by using the controls located at the upper left. You must first uncheck the "All" box to make those selections. Starting or Ending sections cannot coincide with bridge or culvert sections. Getting a Hard Copy You can export this profile drawing by right-clicking anywhere on the chart and selecting "Export this Chart...". You may get a more formal print-out by clicking the [Print] button on the top Ribbon Menu, Home tab. See Printing Results 45 for more information.

43 Plan Drawings By merging the model layout and geometric cross-section data, Channel Studio automatically produces a coordinate-based plan view like the one shown below. To view this, click the Plan tab. Plan maps can be exported as a DXF or image file for further processing. The green lines are the channel extents, overbanks and the channel centerline 33. If the inputs are current with the calculations, the water surface will be overlayed on top. Note that the DXF export option only includes the channel and water surface. Because they are drawn schematically, bridge and culvert structures are omitted. Like the Model view, you can zoom in/out using your mouse wheel. Pan by dragging your mouse in any direction. Use the options located on the left to: Toggle on or off the cross-section labels Zoom to the drawing extents Export the map to an image file or DXF file Use this map for flood plain delineation Plan View Troubleshooting

44 44 On occasion your plan map may appear to be disfigured or jumbled up. This may be due to the cross-section locations exactly coinciding with the river reach connection points. To remedy, just edit the locations of any suspect cross-sections by a small amount (double-click the section line and drag on the Model tab). Getting a Hard Copy You can instantly export this graph as an image file for insertion into other documents by right-clicking anywhere on the plot and choosing, "Export this Chart...". Of course, a more formal presentation is available by clicking on the [Print] button on the top Ribbon Menu, Home tab. See Printing Results 45 for more information Tabulated Results produces tabulated reports for your model. To view these reports, click on the Reports tab. In addition, section-specific numerical results can be viewed on the Input Grid Results tab. This Results tab is very useful when needing to view certain parameters while working on the XSections, Profile or Plan tabs on the main screen. Separate reports are generated for bridge, culvert and weir sections. To view these reports, just click on their respective buttons or double-click on the row shown on the Channel Report. Other options allow you to reverse the order from upstream to downstream as well as export the reports to a text file for further processing. Output Variables Most of the output variables are self explanatory. Just remember the laws of continuity, Q = V x A. Many engineers will attempt to check results using Manning's equation to determine velocity. While open channel hydraulics employs Manning's equation, the methodologies 77 used here are much more sophisticated. But one thing always holds true... Velocity = Q / Area. Current Inputs places a note at the lower left of the reports indicating the status of the outputs. If this note reads, "Results are not current with inputs",

45 45 you need to recompute before accepting the results as shown. Getting a Hard Copy A formal presentation is available by clicking on the [Print] button on the top Ribbon Menu, Home tab. See Printing Results 45 for more information. 2.6 Printing Results You can get hard copies of most anything produces. The best way to get formal-looking reports is by clicking on the [Print] button of the top Ribbon Menu, Home tab. produces reports in a semi-batch mode. For example, on X-sections and Tabulated Reports, you can print out everything all at once. Profiles and Plans must be done individually. Here's how it works: Model, Profile and Plan To print the Model, Profile or Plan views, you must have their respective tabs active. For example, to print the Profile drawing, you must be currently viewing the Profile drawing. You'll then see an automatic print preview from which you can send to your printer for hard copies.

46 46 How to print the Profile plot The drawings will print exactly as they are viewed, encased in a border with project info. Printing Cross-Sections Printing cross-section plots is performed similar to the profile plots, the XSections tab must be active. But with cross-sections you'll have the option to print all sections or a selected set, for example Sections 2 thru 8. You make selections from the Section List by clicking on the sections while holding down the [Shift] key. Sections 2, 3 & 4 are selected in the example below.

47 47 Once your selections have been made, click the [Print] button on the top Ribbon Menu, Home tab. You will be presented with a context menu like this: Choose "Selected Section(s)" to print your sections. Of course, you can select "All Sections" to print the entire project. Numerical Tabulations While viewing the Reports tab, click [Print] for an automatic print preview of the tabulated results. Any bridge or culvert sections will automatically be included in the output. 2.7 Working With Bridges has the capability to include bridge crossings in your model. Any cross-section can be a bridge except Section Number 1 or the very last section. You can add bridge sections to your model at any time. Just follow the same procedure as described in "Adding Cross-Sections 20 ", except you'll use the Bridge/Culvert section button and choose, "Add Bridge Section".

48 48 Bridge sections can include: Elevations for top and bottom bridge deck (chords) (Required) Vertical or sloped abutments on either side of the bridge (Optional) Up to four individual vertical piers (Optional) Bridges are drawn as realistic images Hydraulic modeling is similar to that of the channel sections except the submerged area of abutments, piers and bridge deck are subtracted from the cross-sectional areas. Wetted perimeters are adjusted as well to accommodate the submerged structures including the lower bridge chord. The analysis also considers flow which may be overtopping the bridge, weir flow. Energy losses are computed in 3 parts: 1. From the reach immediately downstream of the bridge to the downstream edge. 2. Through the bridge structure itself to the upstream edge 3. To the reach immediately upstream of the bridge Locating Bridge Sections Each bridge crossing will need to have a Channel section located just downstream of the bridge and one just upstream as shown below. These sections are typically located at the toe of the bridge embankment and

49 49 represent the natural channel adjacent to the bridge. Bridge sections require Channel sections downstream and upstream In addition, a proper model will also include those sections sufficiently downstream and upstream (Sections 1 & 5 in the figure below) to where the flow has fully expanded and is not affected by the structure. These sections become less important as the abutment side restrictions lessen. The Contraction Ratio (CR) as shown below is 1 while the Expansion Ratio is 1.5. These values are user-definable and are set/reset in Project Settings 71. They are used when automatically setting ineffective flow areas 65. Section 3 is the bridge section and is located at the structure centerline

50 50 Procedure The best procedure for locating your bridge and related cross-sections is to first determine the river stations of your sections. For example, given the following: Bridge is located at River Sta 3+00 Deck Width = 50 ft Downstream Distance is 5 ft Reach Length for Section 4 is 5 ft Here's where to place Sections 2, 3 & 4 where the bridge is Section3: Section 2 at the centerline of the bridge minus one-half the deck width minus the distance to Section 2. Sta /2-5 = 2+70 Section 3 at Sta 3+00 Section 4 at the centerline of the bridge plus one-half the deck width plus the distance to Section 4. Sta /2 + 5 = 3+30 Now just add them to your model at these river stations. Remember, you can always adjust the locations and reach lengths at any time either via the Model or by direct entry of the section data. When making adjustments to to section locations on the Model tab, will automatically set the reach lengths and downstream distances for you Adding Bridge Sections Bridge sections are added just like any other channel section. Just click on the Bridge/Culvert Section button on the side tool bar on the Model tab and choose "Add Bridge Section". Move your mouse to the desired river station 47 and click your mouse. Then click the [Ok/Select] button or press escape when finished. A typical model layout containing a bridge section will look like this:

51 51 The model shown here reflects the actual bridge deck width Bridge Section Data It's important to note that bridge, culvert and weir sections do not require geometric (Sta, Elev) data. Rather they inherit the data from the previous downstream section. For example, in the model shown above, Bridge Section 3's geometric data will be bound to Section 2, Including n-values and overbank stationing. If abutments are specified, the program will instead use n-values associated with what was specified in Project Settings 71 for Concrete, in the Right and/ or Left Overbank areas. Not what what entered in the bounding section. All that's needed are inputs pertinent to the structure itself which are described below. Name Optional but it is a recommended input.

52 52 > Reach Length Downstream Distance Enter the distance from the downstream channel section to the downstream edge of the bridge deck. > Bridge Deck Deck Width Enter the width of the bridge deck in the flow direction. (This is not the length from the left side of the channel to the right.) High Chord Elevation Enter the elevation of the top of the bridge deck. This elevation will be used to trigger overtopping flow. The distance between where the high chord intersects the channel banks is what is used as the weir crest length during weir flow calculations. Low Chord Elevation Enter the elevation of the bottom of the bridge deck. When the water surface exceeds this elevation, the lower deck length is added to the wetted perimeter. > Abutments Bridge abutments are optional and may be on a slope. Vertical abutments will have a zero slope. Abutments play a primary role in establishing ineffective flow areas. Station Left, Right Enter the stations where the abutments intersect the channel bottom. If using abutments, the program will replace the overbank n-values with the v-value for concrete in Project Settings 71. Because of this, you should be sure to set the Left and Right Overbank stations of the bounding, downstream cross-section to match the abutment stations. Slope (H:1) Enter the slope of the abutments as horizontal to 1 vertical. For example, for a 3 horizontal to 1 vertical slope, enter 3. This value is used for both left and right sides and must be >=0. > Bridge Piers Piers are optional. You can enter up to four, each with unique station locations and widths. Submerged piers are subtracted from the cross-sectional area of

53 53 flow and will also increase the wetted perimeter. Station Enter the station location of the pier. Pier Width Enter the width of the pier. Apply To accept your inputs, click [Apply]. If you are modeling bridge piers, Channel Studio will immediately setup ineffective flow areas 65 for the downstream and upstream sections. 2.8 Working With Culverts is capable of modeling culverts with various slopes, lengths, sizes, materials and shapes including circular, rectangular, arch and openbottom arch. It also handles a variety of culvert materials and inlet configurations. It uses sophisticated energy-based methods for computing the hydraulic grade line (HGL). It can handle inlet control and outlet control in any flow regime from partial depth, full depth, surcharged, roadway overtopping as well as supercritical flow profiles with hydraulic jump. Methods used are those described in HDS-5 (Hydraulic Design of Highway Culverts). Any cross-section can be a culvert except Section Number 1 or the very last section. You can add culvert sections to your model at any time. Just follow the same procedure as described in "Adding Cross-Sections 20 ", except you'll use the Bridge/Culvert section button and select "Add Culvert Section" from the pop-up menu.

54 54 Culvert section with two rectangular structures Energy losses are computed in 3 parts: 1. From the reach immediately downstream of the culvert 2. Through the culvert structure itself 3. To the reach immediately upstream of the culvert Locating Culvert Sections Each culvert crossing will need to have a Channel section located just downstream of the culvert and one just upstream as shown below. These sections are typically located at the toe of the culvert embankment and represent the natural channel adjacent to the culvert. You should add channel sections down and upstream of the culvert

55 55 In addition, a proper model will also include those sections sufficiently downstream and upstream (Sections 1 & 5 in the figure below) to where the flow has fully expanded and is not affected by the structure. These sections become less important as the embankment side restrictions lessen. The Contraction Ratio (CR) as shown below is 1 while the Expansion Ratio is 1.5. These values are user-definable and are set/reset in Project Settings 71. They are used when automatically setting ineffective flow areas 65. Section 3 is the culvert section and is located at the structure centerline Procedure The best procedure for locating your culvert and related cross-sections is to first determine the river stations of your sections. For example, given the following: Culvert is located at River Sta 4+00 Culvert Length = 100 ft Downstream Distance is 5 ft Reach Length for the upstream channel section is also 5 ft Here's where to place Sections 2, 3 & 4 where 3 is the culvert section: Section 2 at the centerline of the culvert minus one-half the culvert length

56 56 minus the distance to Section 2. Sta /2-5 = 3+45 Section 3 at Sta 4+00 Section 4 at the centerline of the culvert plus one-half the culvert length plus the distance to Section 4. Sta /2 + 5 = 4+55 Now just add them to your model at these river stations. Remember, you can always adjust the locations and reach lengths at any time either via the Model or by direct entry of the section data. When making adjustments to to section locations on the Model tab, will automatically set the reach lengths and downstream distances for you Adding Culvert Sections Culvert sections are added just like any other channel section. Just click on the Bridge/Culvert Section button on the side tool bar on the Model tab and choose "Add Culvert Section". Move your mouse to the desired river station 53 and click your mouse. Then click the [Ok/Select] button or press escape when finished. A typical model layout containing a culvert section will look like this:

57 57 The size of the green box indicates the cilvert's length Culvert Section Data It's important to note that bridge or culvert sections do not require geometric (Sta, Elev) data. Rather they inherit the data from the previous downstream section. For example, in the model shown above, Culvert Section 3's geometric data will be bound to Section 2. Then all that's needed are inputs pertinent to the structure itself which are described below. The input requirements are designed to be minimal but thorough. To enter data, type in the value or select from a drop-down input box, and press [Enter] or the [Tab] key. Data is divided into three categories. Reach Length, Embankment and Culvert. While entering data for the first time, the canvas will automatically display help diagrams to assist in your data entry.

58 58 Name Optional but it is a recommended input. > Reach Length Downstream Distance Enter the distance from the downstream channel section to the downstream edge of the culvert. > Embankment Length Enter the length of the culvert pipe. The length for pipes with mitered inlets is measured along the top or crown of the pipe. Top Elevation Enter the elevation of the top of the embankment. This elevation will be used to trigger overtopping (weir) flow. The distance between where the embankment intersects the channel banks is what is used as the weir crest length during weir flow calculations. > Culvert Shape

59 59 Select the barrel shape from the drop-down list box. Inlet Configuration Select an inlet edge from the drop-down list box. Material Select the barrel material from the drop-down list box. Note: The culvert's roughness coefficient is based on this input. The n-values used can be viewed/edited in the Project Settings 71. Rise Enter the height of the barrel. Span Enter the width of the barrel. Circular sections will always have equal Rise and Spans. Invert Elevation Down Enter the invert elevation for the downstream end of the culvert. Invert Elevation Up Enter the invert elevation for the upstream end of the culvert. Number of Barrels Enter the total number of identical barrels. Six is the maximum allowed and they are each assumed to be at the same elevation and slope. Centerline Station Cosmetic only. This sets the horizontal location of the culvert barrel(s). For example, in the section shown below, the centerline of the barrel is set to 12 ft.

60 60 Apply To accept your inputs, click [Apply]. will immediately setup ineffective flow areas downstream and upstream sections for the Working With Inline Weirs In addition to bridges and culverts, you can add an inline overflow weir to your models. The weir could represent an emergency spillway or a gated overflow. Sharp or Broad Crested? automatically determines the type of weir structure (sharp or broad crested) based on the depth of flow compared to the weir width and will apply the appropriate weir coefficient. If the weir width is less than one-half the depth of flow, it will be considered a sharp-crested weir. Otherwise, it's a broad crested weir. The Quick Results table as well as the printed outputs will indicate which was used. Most weirs are broad crested. Like bridge and culvert sections, the weir section inherits the cross-section geometry of the section just downstream. The weir crest elevation is set by a single input and will stretch across the entire cross-section. You can add weir sections to your model at any time. Just follow the same procedure as described in "Adding Cross-Sections 20 ", except you'll use the

61 61 Weir section button. Typical weir section. The top of embank ment is the weir crest. Energy losses are computed in 3 parts: 1. From the reach immediately downstream of the weir 2. Through the weir structure itself 3. To the reach immediately upstream of the weir Locating Weir Sections Each inline weir will need to have a Channel section located just downstream (a few feet or 1 meter) of the weir and one just upstream as shown below.

62 62 Include channel sections just downstream and upstream of the weir structure. Procedure The best procedure for locating your weir and related cross-sections is to first determine the river stations of your sections. For example, given the following: Inline weir is located at River Sta 4+00 Weir Length (parallel to the channel) = 4 ft Downstream Distance is 5 ft Reach Length for the upstream channel section is also 5 ft Here's where to place Sections 2, 3 & 4 where 3 is the weir section: Section 2 at the centerline of the weir minus one-half the weir length minus the distance to Section 2. Sta 400-4/2-5 = 3+93 Section 3 at Sta 4+00 Section 4 at the centerline of the weir plus one-half the weir length plus the distance to Section 4. Sta /2 + 5 = 4+07 Now just add them to your model at these river stations. Remember, you can always adjust the locations and reach lengths at any time either via the Model or by direct entry of the section data.

63 63 When making adjustments to to section locations on the Model tab, will automatically set the reach lengths and downstream distances for you Adding Weir Sections Weirs sections are added just like any other channel section. Just click on the Weir Section button on the side tool bar on the Model tab. Then move your mouse to the desired river station 60 and click your mouse. Click the [Ok/ Select] button or press [Esc] when finished. A typical Model layout with weir sections will like this: Model with two weir sections Weir Section Data It's important to note that bridge, culvert and weir sections do not require geometric (Sta, Elev) data. Rather they inherit the data from the previous downstream section. For example, in the model shown above, Weir Section 3's geometric data will be bound to Section 2, and Weir Section 6 will be bound to Section 5. All that's needed are inputs pertinent to the structure itself which are described below.

64 64 Weir Section Profile Name Optional but it is a recommended input. > Reach Length Downstream Distance Enter the distance from the downstream channel section to the downstream edge of the weir structure. > Weir Structure Weir Width Enter the width of the weir structure in the flow direction. Weir Crest Elevation Enter the elevation of the top of the weir. This elevation will be used to trigger overtopping flow. The distance between where this elevation intersects the channel banks is what is used as the weir crest length during weir flow calculations. Apply To accept your inputs, click [Apply]. If you are modeling bridge piers, Channel Studio will immediately setup ineffective flow areas 65 for the downstream and upstream sections.

65 Ineffective Flow Areas Ineffective flow areas are portions of a channel cross section that contain water but are not actively being conveyed. This is a common occurrence at channel sections in close proximity to bridge and culvert sections with large embankment constrictions as well as channel sections with wide overbank areas. The velocity of that water, is basically zero and does not contribute to the conveyance of that section until a certain water surface or "Trigger Elevation" is reached. Once this elevation is reached, the area becomes effective again. These inactive flow areas need to be eliminated from the calculations in order to get the most accurate results. This is done by modifying the channel section geometry for both sections, upstream and downstream, from bridge or culvert structures or any other channel section. Ineffective flow areas upstream and downstream from a culvert section How to Add Ineffective Flow Areas

66 66 Adding ineffective flow areas is quite easy. It is done only at the X-Sections tab and is performed graphically. Ineffective flow areas are added and removed on the left and right sides of a section separately using the following buttons. Ineffective flow areas can only be added to channel-type sections, not bridge or culvert sections.to add an ineffective area, click the left or right ineffective area button. Then move your mouse cursor to canvas and drag. The ineffective area will draw itself as a shade of green using your mouse pointer as the station offset and trigger elevation as shown below. When done, release your mouse button. The X, Y coordinates are always shown on the Status Bar at the bottom of your screen. Draw ineffective areas with your mouse Editing an Existing Ineffective Area Once your mouse button has been released, the ineffective area is set. You can edit the area by simply repeating the steps for adding. You can also just click on the area (select) and redrag. You do not need to click on the Add button. To delete an area, select the ineffective area and then click the Delete button.

67 67 You will be prompted to accept or cancel the deletion. Automatic at Bridges & Culverts will automatically add ineffective flow areas to channel sections which are upstream and downstream of bridge or channel sections, provided that option is checked on on the top Ribbon Menu, Compute tab. Below is an example of how a channel section is redefined to remove ineffective flows areas. The section below is just downstream of a culvert section with the top elevation set to Section with ineffective flow areas defined The green shaded areas represent the ineffective flow areas. At sections adjacent to bridge and culvert sections, they are computed based on the Contraction and Expansion Ratios, CR and ER, and the distances between the channel and the bridge or culvert section. At bridge sections, the elevation is equal to the Low Bridge Chord on the downstream side and the Top Chord elevation on the upstream side. The elevation is set to the Top Elevation on culvert sections. Ineffective Flow Areas Are Not Permanent It should be noted that ineffective flow areas are not permanent, in that they change into effectively carrying flow when the computed water surface elevation is above the defined ineffective flow area elevation. To make them permanent, raise the top trigger elevation to the highest point on the channel section. Do Not Affect Overtopping Flows

68 68 Ineffective flow areas do not affect overtopping flow calculations and are not included in the flow area or wetted perimeter quantities as shown on the reported outputs Adding a Background Map supports the addition of coordinate referenced background maps for display behind your Model and Plan views. A variety of file formats are supported including, bmp, jpg, png as well as cad DXF files. For image formats, you have the option of rectifying the picture by entering in coordinates for the lower left and top right corners of the map. The program automatically assumes the extents implied in DXF files, so no coordinate inputs are required or allowed. How to Add a Background Map Background maps must be added on the Model tab. Once added, the map will display on both Model and Plan tabs. It is recommended that you add background maps prior to adding your river reaches. When importing image-type files, be sure the map is plenty large to work on. You can zoom in, but you cannot zoom out past the image extents. Once a map has been imported, you can zoom in or out with your mouse wheel as well as pan by dragging your mouse in any direction. To add a map, click the Map button on the side toolbar from the Model tab. Then Choose "Import Background Map". Then browse to the desired file and click [Open]. The map will display automatically and you will be prompted to set the map extents by the following screen:

69 69 This screen allows you to set back ground map extents Enter the X, Y coordinates associated with the lower left and upper right corners of the map and click [Ok]. River reach sytem with back ground map ready for sections Resetting the Map Coordinates The map coordinates can be adjusted at any time by selecting, "Set Background Extents" from the Map menu shown above. Clearing the Background Map You may unload the map from your display by selecting "Clear Background

70 70 Map" from the Map menu shown above. Once cleared, the map will need to reopened to be displayed again. Background Maps are not saved with project files but their locations are. When the project is reopened, will look in the "Location" for the map file and reload it. If you plan to share your project with someone, be sure to provide them with the actual map file Custom Labels allows you to annotate your model with custom labels. They can be placed anywhere on the model and can be of many different fonts and colors. You can move them around later by just selecting them, Click with your mouse. Custom labels will also appear on the Plan view but can only be edited from the Model. Adding Labels To add a new label, follow these steps: 1. Click the [Add Custom Label] button from the side toolbar. 2. Move your cursor over to the canvas and drag a rectangle large enough to contain the text you want to add. 3. Choose the font style, size and color from the top Ribbon menu, Home tab. Note that you can change the font at any time, even while typing.

71 71 4. Type in the desired text inside of the rectangle. Editing Labels To edit an existing label, simply double-click the label. Moving Labels Once a label has been added it can be moved by selecting it and dragging it to its new location. Deleting Labels To delete a label, click on the text to highlight and then click the [Trash] button on the side toolbar Project Settings There are selected input variables which you and the software use on a routine basis that typically do not need to be re-entered for each project. These include n-values for culverts, expansion and contraction ratios, coefficients and system units. keeps these variables in its Project Settings. You can view or edit these at any time. System units, however should be set prior to starting a new project or opening one with units different than what is currently being used..

72 72 Once these variables are set, there's no need to review them unless your project parameters need to. To edit these settings, click the [Project] button on the top Ribbon Menu, Home tab. This opens the Project Settings screen. Default settings

73 73 Here's a description of each setting: > This Project only These items refer to the current project. Title This is the formal title for this project and will be shown on all printed reports. Enter any meaningful alphanumeric name. Units The system units must be changed prior to the start or opening of a new project. Choose U.S. Customary or Metric. Flow Profile ID Enter the name for each flow profile, for example, "1-year", "10-year", "100year". These names will appear on your output only. > Culverts Specify n-values to be used for the various types of culvert materials. > Channels Enter the coefficients and ratios for Expansion and Contraction. Expansion and Contraction Ratios (ER, CR) are used to configure ineffective flow areas. Coefficients are used during energy grade line calculations. See, "Computational Methods 77 " for more information. Once the settings are edited, click the [Apply] button. Then [Close]. Default Settings Reset Culvert and Channel settings to factory defaults by clicking [Reset]. Then [Close] Saving and Retrieving Project Files uses only one file: Project Files These files are used to store all of your project data and will have a ".chs" extension. Saving Projects

74 74 works much like a spreadsheet or word processor. To save a project, select "Save Project" from the "File" menu. If you are saving this file for the first time, select "Save Project As...". When using "Save Project" the program will automatically save the project under its current name. Opening Projects To retrieve a project, select "Open Project" from the "File" menu button or select a file from the Recent Projects list on the right Modeling Best Practices has gone through great efforts to make open channel modeling as easy as possible. From time-to-time however, things can get a little confusing. After all, it's applied physics. Below are some helpful tips to keep you in the fairway. Practical Tips Always start with a simplified model and make sure it's running without errors. Then add complexity to the model in incremental steps. Unless you are modeling for a finished plan rendering, don't worry too much about the exact alignment of your river reaches. They are station-referenced but are basically place-holders for your cross-sections. Your final results depend the most on the cross-section geometry and reach lengths. Add cross sections at representative locations locations where changes occur in discharge, slope, velocity, and roughness. The model only knows what you provide for it. Avoid placing cross-sections at or very near the PC and PT points on curved river reaches. Large uniform rivers with mild to flat slopes require cross sections about

75 75 every 1,000 ft (300 m). Narrow, confined channels in urban areas need cross sections about every 500 ft (150 m) or less. As a "rule-of-thumb", cross sections can be spaced at about 5 times the channel widths. Cross sections should be deep enough to contain the inputted discharge values. Otherwise, the program will vertically extend the cross section to contain the flow. You will see a warning to this effect on the section plots. Always add cross sections just downstream and upstream of bridge, culvert and weir crossings. Steep channels flowing at high velocities require more cross sections, especially if locating hydraulic jumps are important. Scrutinize any cross section where the computed water surface elevation is at critical depth. This means the program could not balance the traditional energy equation procedure. This is typical on steep slopes but not on flatsloped rural channels.

76 Computational Methods

77 77 Computational Methods 3 Computational Methods This section describes the computational methodologies employed by. It is highly recommended that you review the computational methods and equations used so that you will better understand the output and results. It is not the intention of this section to provide the basis of the theories used or to demonstrate how they were derived. But rather provide the actual equations and methods employed by the software. Methodology The program uses only widely accepted methods within the industry. Procedures described in HEC-RAS and HDS-5 are the primary methodologies. This section will provide a summary of the concepts used but it is not intended to be all-encompassing. Below is a list of publications which provide details on the methods used. FHA Hydraulic Engineering Circular No. 22 Third Edition, 2009 FHWA Hydraulic Design of Culverts (HDS5) Third Edition, 2012 U.S. Army Corps of Engineers, HEC-RAS, River Analysis System, Hydraulic Reference Manual, Channels performs one-dimensional water surface profiles for steady, gradually varied flow in open channels. It computes profiles for subcritical as well as supercritical flow regimes. The basic computational procedure is based on the solution of the one-dimensional energy equation. Energy losses are evaluated by friction using Manning's equation, and using contraction/ expansion coefficients multiplied by the change in velocity head. Note that computes uses units and coefficients consistent with the Units Settings. In other words, when using metric units, the program does not convert variables to English prior to performing calculations and then reconvert back to Metric. Water surface profiles are computed from from one cross-section to the next, beginning at the most downstream section working upstream. It solves the Energy equation using an iterative procedure known as the Standard Step method. The Energy equation used is as follows:

78 78 Computational Methods Where: Z1, Z2 = Channel invert elevations Y1, Y2 = Depth of water at cross-section V1, V2 = Average velocity at cross-section a1, a2 = Velocity-weighting coefficients he = Energy head loss g = gravity (9.81) Diagram of Energy equation The energy head loss, he, between two cross sections is comprised of friction losses and contraction or expansion losses. The equation for the energy head loss is: Where: L = Discharge-weighted reach length

79 Computational Methods 79 Sf = Friction slope between two sections C = Expansion or contraction loss coefficient The discharge-weighted reach length, L, is calculated as: Where: LLOB, LCH, LROB = Reach lengths for the left overbank, main channel, and right overbank, respectively QLOB, QCH, QROB = Flows for the left overbank, main channel, and right overbank, respectively The velocity-weighted coefficient, Alpha is computed as follows: Where: AT = Total flow area of cross section KT = Total conveyance of cross section ALOB, ACH, AROB = Flow areas of left overbank, main channel and right overbank, respectively KLOB, KCH, KROB = Conveyances of left overbank, main channel and right overbank, respectively Conveyance, K, is computed as:

80 Computational Methods 80 Where: Cm = Manning Coefficient = (1.00) n = Roughness coefficient A = Cross-sectional area of flow R = Hydraulic radius = Area/Wetted Perimeter Friction Losses offers three different methods for computing friction losses. In general, friction loss is computed as the product of Sf and the dischargeweighted reach length, L. The friction slope (slope of the energy grade line) at each cross section is computed as follows: Average Conveyance This is the default method used and is known to provide the best overall results compared to the Average Friction Slope and Geometric Mean. Where: Sf = Friction slope Q = Total flow at the cross-section K = Total conveyance at the cross-section Average Friction Slope

81 81 Computational Methods Where: Sf = Friction slope Sf1, Sf2 = (Q/K)2 Geometric Mean Where: Sf = Friction slope Sf1, Sf2 = (Q/K) Expansion Contraction Losses Contraction and expansion losses are typically small compared to friction losses but become more significant around culvert and bridge openings. evaluates these losses using the following equation: Where: hce = The energy loss from expansion or contraction C = The contraction or expansion coefficient (See Project Settings for default values) 71 The program assumes that a contraction is occurring whenever the velocity head downstream is greater than the velocity head upstream. Likewise, when

82 82 Computational Methods the velocity head upstream is greater than the velocity head downstream, the program assumes that a flow expansion is taking place. Losses are tak en into account due to contraction and expansion Computation Procedure Water surface profiles are computed from from one cross-section to the next, beginning at the most downstream section, Section 1 along with the Starting Tailwater Elevation, working upstream. It solves the Energy equation using an iterative procedure known as the Standard Step method. Here's how it works: 1. The program assumes a water surface elevation at the next upstream cross section (or downstream cross section if a supercritical profile is being calculated). 2. Based on the assumed water surface elevation, determine the corresponding total conveyance and velocity head. 3. With values from step 2, compute the Friction Slope (Sf ) and then the

83 Computational Methods 83 energy loss, he. 4. With values from steps 2 and 3, solve the Energy equation for the water surface at point 2, WS2. 5. Compare the computed value of WS2 with the value assumed in Step 1. Steps 1 through 5 are repeated until the values agree to within feet (0.004 m). assumes water surface elevations by taking the average of the computed and the assumed elevations. In other words, W.S. new = W.S. assumed * (W.S. computed - W.S. assumed). The very first trial, however is set by projecting the previous cross-sections water depth onto the current cross-section. will use up to a maximum of 25 trials to obtain a balance. If a solution cannot be found, it assumes critical depth and moves onward to the next section. If the calculation option "Supercritical Profiles" is check on, then will automatically compute a supercritical profile Supercritical Flow Profiles will use up to a maximum of 25 trials to compute subcritical water surface profiles. If a solution cannot be found, it assumes critical depth and moves onward to the next section. If the calculation option "Supercritical Profiles" is checked on, then will automatically compute a supercritical profile.

84 84 Computational Methods Supercritical Profile uses the same procedure for computing supercritical profiles as it does for subcritical except that it does not consider losses due to contraction and expansion. The procedure begins at the most upstream section that was found to be at critical depth, uses that as a known starting elevation, and works downstream. Note that supercritical profiles are not computed through bridge sections. These will be skipped. Hydraulic Jumps Hydraulic jumps occur when the water surface passes through critical depth. When this happens, the Energy equation is not considered to be applicable. It cannot account for all of the losses generated by Manning's equation. Thus a different approach is used involving concepts of momentum. The Momentum Principle is used for determining depths and locations of hydraulic jumps.the program calculates a supercritical profile in the downstream direction until it reaches a cross section that has both a valid subcritical and a supercritical answer. During these calculations, Channel Studio computes the momentum M1, and compares it to the momentum developed during the subcritical profile calculations, M2. If M1 > = M2, it is established that a hydraulic jump must occur between these two cross-sections.

85 85 Computational Methods Momentum, M1, of the subcritical profile is greater than or equal to the momentum, M2, of the supercritical profile. Note that M is also known as Specific Force (SF) and is reported as such on the Section Results tab. Where: Where: Q = Flow rate A = Cross-sectional area of flow Y = Distance from the water surface to the centroid of A The location of the jump is somewhere along the channel reach when M1 = M2 and is reported as the distance from the downstream section. If M2 > M1, then the upstream force is stronger than the downstream force and the jump just gets pushed through to the next section. The length of the jump however is difficult to determine, especially in natural channel sections. There have been many experimental investigations which have yielded results which are contradictory. Many have generalized that the jump length is somewhere between 4 and 6 times the Sequent or subcritical depth. assumes 5. As mentioned in 38, hydraulic jump locations may be better located by inserting an interpolated section and rerunning the computations. 3.2 Bridges uses the same energy-based procedures as it does for Channel sections with a few exceptions. During calculations the area of the bridge below the water surface is subtracted from the total area, and the wetted perimeter is increased where the water is in contact with the bridge structure.

86 86 Computational Methods Bridge section shows the water surface for both down and upstream ends The program formulates two cross sections inside the bridge. One just inside the downstream end and the other just inside the upstream end. It combines the channel geometry information of the previous downstream channel section with the bridge geometry (abutments, deck and piers) and uses this newlyformed section for both up and downstream bridge sections. Bridge profile uses geometry from Section 2 to describe the bridge channel draws a realistic water surface using bezier curves between from the downstream section to the bridge; through the bridge; and to the upstream section. does not compute supercritical profiles through bridge sections but it does compute critical depth automatically.

87 Computational Methods 87 Pressure Flow If the computed water surface elevation exceeds the lower bridge deck elevation on both upstream and downstream ends, will compute an alternate water surface elevation using the the following orifice equation. Where: A = Net area of bridge opening H = The difference between the energy grade line elevation upstream and the water surface elevation downstream Co = Orifice coefficient = 0.80 Bridge under pressure flow The pressure flow calculation is compared to the answer given by the Standard Step procedure. The higher of the two is used. Overtopping Flow If the computed water surface profile exceeds the top bridge chord elevation, will initiate an iterative procedure for computing overtopping flow, similar to flow over a broad crested weir.

88 88 Computational Methods Bridge flowing under pressure and weir flow It is a simple matter to calculate the flow across the roadway for a given upstream water surface elevation using the weir equation. The problem is that the deck overflow plus the flow beneath the bridge flow must equal the total flow. A trial and error process is necessary to determine the amount of the total flow passing through the bridge and the amount flowing across the top chord. uses the following broad crested weir equation: Where: Q = Overtopping flow Cw = Broad crested weir coefficient = 2.66 (1.5) L = Crest width H = HGL High Bridge Chord elevation (The approach velocity is neglected) Adjustment for Submergence Weir performance can be affected by submergence, i.e., when the tailwater rises above the weir's crest and reduces the flow.

89 Computational Methods 89 Bridge deck fully submerged The equation for the reduction in flow is: Where: Qs = Submerged flow Qr = Unsubmerged flow from standard weir equation H1 = upstream head above deck H2 = downstream head above deck 3.3 Culverts computes energy losses, caused by structures such as culverts, in three parts, similar to the procedures for bridge crossings. The layout of cross sections, the use of the ineffective areas, the selection of loss coefficients, and many other aspects of bridge analysis apply to culverts as well. The first part consists of losses that occur in the reach immediately downstream from the structure, where an expansion of flow takes place. The second part consists of losses that occur as flow travels into, through, and out of the culvert. The last part consists of losses that occur in the reach immediately upstream from the structure, where the flow is contracting

90 Computational Methods 90 towards the opening of the culvert. See "Working With Culverts sections in your model. 53 " for further discussion on locating culvert Why Culvert Modeling Can Be Difficult follows calculation procedures described in HEC-22 and HDS-5. Culverts are complicated. Their analysis is difficult and often times confusing. Their flow regimes change with seemingly little reason. Their barrels may flow full or partly full but full flow throughout their length is rare. Generally at least part of their length is in partial flow. The upstream end may be totally under water while underneath, the barrel is in supercritical flow ending downstream in subcritical flow. Raise the tailwater a little and the entire flow regime changes to full. sorts out these hydraulic anomalies by using time-tested methods and some sophisticated algorithms. This chapter outlines those methods. It starts with an overview of a puzzling concept... Inlet and Outlet Control. Inlet and Outlet Control Culverts flow under two regimes; Inlet Control and Outlet Control. Inlet control implies that it is more difficult for water to get in the pipe than it is to get through it. During outlet control, it is more difficult for flow to get through the barrel than it is getting inside of the barrel.

91 Computational Methods 91 Inlet control is a lot like traffic going from a four-lane highway into a two-lane tunnel. As the traffic nears the tunnel, it must squeeze together causing a traffic jam that affects the cars approaching the tunnel. Once in the tunnel, traveling is easier and traffic speeds up. You ll find that culverts often flow in partial depth throughout its barrel while under inlet control. Traveling is easier because most of the cars are still trying to get in the tunnel. If, on the other hand, there was an accident inside of the tunnel, traffic would slow down even more after entering. Traveling is more difficult. This is outlet control. Inlet control is largely influenced by the entrance geometry of the pipe such as edge configuration, pipe area and shape. Outlet control is influenced most by n-value (barrel roughness), pipe area, shape, length and slope. So how does one determine the flow regime of a culvert? The solution is to compute the hydraulic profile assuming both exist, and then selecting the one that produces the highest headwater, Hw. Calculation Procedure Once a water surface is computed inside the culvert at the downstream end, the program then performs the energy based, Standard Step calculations through the culvert until the water surface and energy are obtained inside the culvert at the upstream end. The last step is to add an entrance loss to the computed energy to obtain the upstream energy (Hw) just outside of the culvert. It is here that both solutions for inlet control and outlet control are compared. The highest is used for Hw. The newly computed energy grade line (EGL) is then used as the starting EGL for the next upstream section. Its starting HGL is obtained by backcalculating the water surface that corresponds to the EGL Outlet Control Outlet control flow conditions are calculated based on energy balance. The total energy required to pass the flow through the culvert barrel is the sum of the entrance loss (He), the friction losses through the barrel (Hf ), and the exit loss (Ho).

92 Computational Methods 92 Culvert flowing under outlet control Exit Loss The exit loss is computed by the following equation: Where: V = Velocity exiting the culvert g = Acceleration due to gravity Friction Loss uses the energy-based Standard Step method when computing the friction loss. This methodology is an iterative procedure that applies Bernoulli's energy equation between the downstream and upstream ends of the culvert. It uses Manning's equation to determine head losses due to pipe friction. This method makes no assumptions as to the depth of flow and is only accepted when the energy equation has balanced. The following equation is used for all flow conditions:

93 93 Computational Methods Where: V = Velocity Z = Invert elevation Y = HGL minus the invert elevation Friction losses are computed by averaging the friction head as follows: Where: HL = Energy head loss due to friction hf1 = Friction head at the downstream end hf2 = Friction head at the upstream end Where: Km = (1.0) n = Manning's n A = Cross-sectional area of flow R = Hydraulic radius Composite n-values uses the Horton-Einstein equation to compute a composite nvalue for open-bottom arch sections.

94 Computational Methods 94 Where: nc = Composite n-value Pi = Wetted perimeter of subdivision i ni = n-value for subdivision i P = Total wetted perimeter Entrance Loss The entrance loss is a function of the velocity head in the barrel, and is expressed as a coefficient times the velocity head. Where: V = Velocity exiting the culvert g = Acceleration due to gravity Ke = Coefficient based on various inlet configurations provided in HDS Inlet Control Inlet control occurs when it is harder for the flow to get through the entrance of the pipe than the remainder of the pipe barrel. The profile below illustrates a type of inlet control flow. The control section is at the inlet end of the culvert. Depending on the tailwater and culvert slope, a hydraulic jump may occur downstream of the inlet.

95 Computational Methods 95 Culvert flowing under inlet control The following inlet control equations are used. If Hw is above the pipe crown the submerged equation is used. Otherwise the unsubmerged equation is used. Submerged Unsubmerged Where: Hw = Headwater depth above invert D = Culvert Rise Q = Flow rate A = Full cross-sectional area of pipe K, M, c, Y = Coefficients based on inlet edge configurations S = Culvert slope

96 Computational Methods Inline Weirs Weir Flow Weir flow is automatically computed for Weir sections. The program employs the standard weir equation as described below. If the weir structure width (b) is less than the one-half the flow depth (H), it is considered a sharp crested weir. Otherwise, it's treated as a broad crested weir. Sharp Crested Weir Broad Crested Weir

97 97 Computational Methods Overtopping Flow Overtopping is automatically computed for bridge and culvert sections and will begin when the headwater, (Hw) rises to the elevation of the roadway or deck as shown in the profile below. The overtopping will usually occur at the low point of a sag vertical curve on the roadway. The flow will be similar to flow over a broad crested weir. Culvert with overtopping flow It is a simple matter to calculate the flow across the roadway for a given upstream water surface elevation using the weir equation. The problem is that the roadway overflow plus the flow through the culvert barrel must equal the total flow. A trial and error process is necessary to determine the amount of the total flow passing through the culvert and the amount flowing across the top chord. For Weir, Bridge and Culvert sections, uses the following weir equation: Where: Q = Overtopping flow Cw = Broad crested weir coefficient = 2.66 (1.5) - Bridges, Culverts and Weirs Cw = Sharp crested weir coefficient = 3.33 (1.84) - Weirs only L = Crest width H = HGL High Chord elevation (The approach velocity is neglected)

98 98 Computational Methods Adjustment for Submergence Weir performance can be affected by submergence, i.e., when the tailwater rises above the weir's crest and reduces the flow. Embank ment fully submerged The equation for the reduction in flow is: Where: Qs = Submerged flow Qr = Unsubmerged flow from standard weir equation H1 = upstream head above embankment H2 = downstream head above embankment 3.5 Supercritical Flow has the ability to compute supercritical flow profiles with hydraulic jumps automatically. During friction loss calculations, if the energy equation cannot balance, the software reverses the calculation procedure, i.e. from upstream to downstream, and computes the supercritical profile.

99 Computational Methods 99 Hydraulic jump in culvert It should be noted that does not compute supercritical flow profiles for arch shapes. In these cases, critical depth is assumed. Hydraulic Jump The Momentum Principle is used for determining depths and locations of hydraulic jumps. At each step (one tenth of the culvert length) during supercritical flow calculations, Culvert Studio computes the momentum and compares it to the momentum developed during the subcritical profile calculations. During these calculations, computes the momentum M1, and compares it to the momentum developed during the subcritical profile calculations, M2. If M1 > = M2, it is established that a hydraulic jump must occur between these two cross-sections. Momentum, M1, of the subcritical profile is greater than or equal to the momentum, M2, of the supercritical profile.