The three Run manager parameters, Maximum Number of Segments, Minimum Travel Distance and the Minimum Travel Time in InfoSewer and H2OMAP Sewer affect the shape and flow attenuation of the flow in a link.  The effect of decreasing the Minimum Travel Time is to reduce the peak flow and spread out the flow as the number of segments increases(Figure 1).  The larger the Minimum Travel Time, which has the effect of decreasing the number of segments in a link up the limit of the parameter Maximum Number of segments, the smaller the peak and the more attenuation of the flow in InfoSewer.

There is three ways to control attenuation in InfoSewer: (1) use the flow attenuation option, (2) increase the Maximum Number of Segments per link and (3) decrease the Minimum travel distance.    You can also use all three parameters to make more segments per link for long links and only a few segments for short links.

Figure 1.  Effect of the Minimum Travel Time in InfoSewer and H2OMAP Sewer

The three Run manager parameters, Maximum Number of Segments, Minimum Travel Distance and the Minimum Travel Distance in InfoSewer and H2OMAP Sewer affect the shape and flow attenuation of the flow in a link.  The effect of decreasing the Minimum Travel Distance is to reduce the peak flow and spread out the flow as the number of segments increases(Figure 1).  The smaller the minimum travel distance, which has the effect of increasing the number of segments in a link up the limit of the parameter Maximum Number of segments, the smaller the peak and the more attenuation of the flow in InfoSewer. 

There is three ways to control attenuation in InfoSewer: (1) use the flow attenuation option, (2) increase the Maximum Number of Segments per link and (3) decrease the Minimum travel distance.    You can also use all three parameters to make more segments per link for long links and only a few segments for short links.

Figure 1.  Effect of the Minimum Travel Distance in InfoSewer and H2OMAP Sewer

You can use this macro for MATLAB or some other DOS based program by using the Tools command of SWMM 5 and configuring the EXCEL file option.  If you use the EXCEL tool then your SWMM 5 input file will be opened up in EXCEL and you can use this macro to make a fixed format file for SWMM 5.  Note, SWMM 5 does not use fixed format but other programs may need it for reading,  You adjust the column widths in the macro for your program.

Here is the macro, which is placed  in Excel using these command:

1. Copy the code above.
2. Open Excel.
3. Alt + F11 to open the Visual Basic Editor.
4. Click Insert-Module from the menu.
5. Paste the code into the window that appears at right.

Option Explicit

Sub CreateFixedWidthFile(strFile As String, ws As Worksheet, s() As Integer)

    Dim i As Long, j As Long

    Dim strLine As String, strCell As String

     'get a freefile

     ' source is http://www.vbaexpress.com/kb/getarticle.php?kb_id=759

    Dim fNum As Long

    fNum = FreeFile

     'open the textfile

    Open strFile For Output As fNum

     'loop from first to last row

     'use 2 rather than 1 to ignore header row

    For i = 1 To ws.Range("a65536").End(xlUp).Row

         'new line

        strLine = ""

         'loop through each field

        For j = 0 To UBound(s)

             'make sure we only take chars up to length of field (may want to output some sort of error if it is longer than field)

            strCell = Left$(ws.Cells(i, j + 1).Value, s(j))

             'add on string of spaces with length equal to the difference in length between field length and value length

            strLine = strLine & strCell & String$(s(j) - Len(strCell), Chr$(32))

        Next j

         'write the line to the file

        Print #fNum, strLine

    Next i

     'close the file

    Close #fNum

End Sub

 'for example the code could be called using:

Sub CreateFile()

    Dim sPath As String

    sPath = Application.GetSaveAsFilename("SWMM5_Fixed_EXPORT", "Text Files,*.inp")

    If LCase$(sPath) = "false" Then Exit Sub

     'specify the widths of our fields

     'the number of columns is the number specified in the line below +1

    Dim s(15) As Integer

     'starting at 0 specify the width of each column for the SWMM5 File, alter the columns if you need more columns in your data input file

    s(0) = 40

    s(1) = 20

    s(2) = 20

    s(3) = 20

    s(4) = 20

    s(5) = 20

    s(6) = 20

    s(7) = 20

    s(8) = 20

    s(9) = 20

    s(10) = 20

    s(11) = 20

    s(12) = 20

    s(13) = 20

    s(14) = 20

    s(15) = 20

     'for example to use 3 columns with field of length 5, 10 and 15 you would use:

    'dim s(2) as Integer

     's(0)=5

     's(1)=10

     's(2)=15

     'write to file the data from the activesheet

    CreateFixedWidthFile sPath, ActiveSheet, s

End Sub