The Culvert Information portion of the Crossing Input Window allows you to specify the culvert type, size and placement.

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• Culvert Number

  If the site has multiple culvert barrels or bays you can manage multiple culverts here. Each culvert can have the same geometry, or each can have a unique geometry, for example an overflow pipe. Flow is split and routed through each culvert based on the headwater elevation as according to a flow splitting algorithm.

   

  Add Culvert insert a new culvert with the data fields left blank.

   Copy Culvert  adds a new culvert with the same data as the currently active culvert.

   Delete Culvert to remove the currently active culvert from the analysis.

  Scroll through multiple culverts.

   

  Note: The culvert data that is actively displayed at the time of Calculation will be the culvert used in the evaluation for fish passage .

• Culvert Shape

  Choose a culvert shape from the drop down list. Options include circular, box, arch, pipe arch (single radius), ellipse and aluminum box. If Pipe-Arch is chosen, a window will open containing a list of predefined sizes to select from.  When a pipe arch dimension is selected they can be reviewed by pressing the Dim. button. For a description of the different culvert types and shapes, see Culvert Shapes.

• Details

  When a culvert shape that has pre-defined dimensions is chosen the Details button will open another window that displays the dimensions of the chosen culvert. You can choose from other dimensions in this window.

• Culvert Dimensions

  Culvert Dimensions text here

• Material

  Use the drop down menu to select the type of material, the culvert is constructed of (concrete, metal or plastic) and the type of corrugation, if any. See Culvert Material and Construction and Corrugations for more information.

• Installation

  The installation field has two options, At Grade and Embedded:

  At Grade - Standard installation, with the culvert bottom (invert) placed on the surface of the channel bed.

  Embedded - Culvert invert is depressed (countersunk) below the stream bed to retain bed material, producing a natural channel bottom throughout the culvert.  The sunken or embedded installation can also be used if the culvert bottom has been lined with concrete or other material.  After selecting the Embedded option enter either the effective depth the culvert invert is placed below the stream bed material (if it is concrete lined, enter the thickness of the concrete) or enter the percent of the culvert rise that is embedded.  FishXing will auto calculate the corresponding value. For additional information see Embedded Culverts .

  Note: FishXing assumes that the embedded depth is uniform throughout the length of the culvert. The program does not directly allow for a partially embedded culvert where the inlet or variable substrate depths within the culvert.

• Culvert Roughness

  Enter or select a roughness coefficient for the selected culvert material.  FishXing uses Mannings's Roughness Coefficient (n) by default, but you can also use Darcy Friction Factor (f) or the Chezy Coefficient (c). Default values are entered automatically when you select the culvert Construction Type. The ellipsis button (...) will open a new window with a detailed list of Manning's n values.

• Bottom Roughness

  This field is only activated for embedded or open-bottom arch culverts.  Enter or select a Manning's roughness coefficient (n) for the material along the culvert bottom. This is likely similar to the streambed material in the upstream channel, but it can also be material that is engineered such as smooth or roughened concrete pavement or other material. The ellipsis button (...) will open a new window with a detailed list of Manning's n values.

• Culvert Length

  Enter the total length measured from the culvert inlet bottom to the culvert outlet bottom.

• Culvert Elevations and Slope

  FishXing allows you to choose between entering the bottom elevations and culvert length or entering the culvert slope.  The other is auto-calculated once the culvert length and outlet elevation have been entered.  To select which field you wish to enter, by activating the radio button adjacent to the field.  The non-selected field will be grayed-out and display the auto-calculated value.  This feature allows you to either use a surveyed inlet elevation or enter a culvert slope to determine the resulting inlet elevation.

   

  Elevation of Inlet Bottom - Enter the elevation of the inlet bottom (inlet invert).  If the culvert is embedded or is an Open-Bottom culvert, the inlet bottom is defined as the elevation of the top of the channel bed at the inlet. FishXing uses the embedded depth to place the bottom of the culvert.

   

  Culvert Slope - Enter the percent slope of the culvert bottom.  If the culvert is embedded or is an open-bottom arch, enter the slope of the bed within the culvert.

  Note: FishXing assumes the bottom slope of an embedded or open bottom culvert is the same as the culvert slope. FishXing cannot model hydraulics of culverts containing a bottom slope substantially different from the slope of the installed culvert.  For example, if the embedded depth at the culvert inlet is much less than at the outlet. See Embedded Culverts for more information.

   

  Elevation of Outlet Bottom- Enter the elevation of the culvert outlet bottom (outlet invert).  If the culvert is embedded or is an Open-Bottom culvert the outlet bottom is defined as the elevation of the top of the channel bed at the outlet.

   

  Note: All elevations should be tied to a common datum.

• Entrance Loss

  The Entrance Loss Coefficient (Ke) is a parameter that describes the amount of energy lost as the water passes through the culvert inlet.  The entrance loss coefficient is based on the culvert inlet configuration.  Larger coefficients are associated with greater energy loss. See Inlet Head Loss Coefficient for more information.