Changing the SWMM system Unit

Hi all,

Does any body know if it would be somehow possible to change system units of SWMM projects. For example,  if a project's input data was in british units, is there a way to change automatically all input and output values into SI unit.

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  • The simple way is here (SWMM5.1)


  • Hi, I could go few steps forward now. Using Excel tool I opened, I edited (inch to mm), closed, when asked to save I gave the same name as the temporary file (e.g. swm45E3.tmp), clicked yes for update. This works good for some projects, but some projects what I am getting is 'List index out of bounds ()' message after I finished all editing! what does this mean, and why does this happen?
  • Yes, I have the same settings. I've attached example .inp files and my excel sheet I got3293149524?profile=RESIZE_1024x1024
    • Hi, It works for me using SWMM 5.0.021 and these settings.  I can also open it in Excel if I save it as a Tab delimited file and then open up Excel using the INP file directly.  I looked at the INP file you sent to me and it did not have the TAB character so you probably did not save the file  with the Tab setting check-box on.



  • Hi, It should show up as tab and thus in separate columns.  Have you told SWMM 5 that you inp file is tab delimited or should be saved with Tabs?



  • Hi, You can use the Excel tool to convert the flow and other units to SI units but there is no tool directly to do the conversion for you.
    • Hi Robert, I have another problem when working with the Excel tool. When I open the .inp file using the Excel tool, I am getting all the records in the first column of the resulting Excel sheet. Procedure I am using is (from the SWMM GUI:Tools-->Excel-->from excel I navigate to the .inp file-->from the message box that pops: Ichecked Separated,MS-DOS (PC-8), Tab-delimited, standard respectively. The excel file I am getting puts all the values in the first column, making editing difficult. I am using Excel-2007, any help?
    • Thanx. Aditional reference to your post on ''SWMM 5 Tools'' also helped on how to add-in Excel to SWMM. 
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