time step in SWMM5

Dear All,

I have probably found a problem in the beta version of SWMM5, so I want tell you how I solved it. I tried to make an easy project (runoff+extran) to test the new release, but when I changed the default value of time steps (i.e.: wet weather, dry weather, routing time step, reporting time step), the program did not accept the new value anymore, untill I put in 1 hour or more.

So I have opened the project file (*.inp) with a text editor and I have compared it with example1.inp (in bundle with SWMM5), and I have found a different syntax of time steps: in my project the hours, minutes and seconds were divided by "." and in example1 by ":". So I manually changed my file, and everything goes. Then I controlled the time step window and I saw my time steps (10 seconds) on the left, under the writing "hours". I don't know if this is a SWMM5 source code bug, but this is what I found! I hope I helped someone of you with my problem!

Greetings to All,
Camorani Giorgio
giorgio.camorani@MAIL.ING.UNIBO.IT

Giorgio,

You could have also edited the time steps in the SWMM GUI window and entered 00:00:05, for example, as the Routing time step in SWMM 5. You always enter the time in HR:Min:Sec as it says at the top of the GUI dialog. It was not necessary to edit the *.inp file to make this change. I snipped a little of the output file to show you the general format for time in SWMM 5.

****************
Analysis Options
****************
Flow Units ................ CMS
Flow Routing Method ....... DW
Starting Date ............. 06-04-1979
Starting Time ............. 00:00:00
Ending Date ............... 06-04-1979
Ending Time ............... 12:00:00
Wet Time Step ............. 00:15:00
Dry Time Step ............. 01:00:00
Routing Time Step ......... 00:00:05
Report Time Step .......... 00:00:10

Best Regards,
Bob Dickinson
DickinsonRE@CDM.COM

Dear All,

I have Just found the real problem: it was not SWMM5, but the default settings of WindowsXP. In fact, by default WindowsXP uses the "." as hours separator (Control Pannel-International options-Houre); i changed it in ":" and now everything is all right (even without manually change the *.inp file...).No bug! Sorry!

Greetings to all,

Camorani Giorgio
giorgio.camorani@MAIL.ING.UNIBO.IT

Both Giovanni Di Conza and now Giorgio Camorani have a legitimate complaint about SWMM 5 not accepting edits made to the time step parameters in its Analysis Options dialog window. As Gabriele Freni pointed out, the problem is related to the Regional Settings one uses for Windows. In this case, a period '.' was being used by Windows for the time separator character instead of the colon ':' that SWMM 5 expected to see. When the input file generated from the GUI was passed to the engine, the time step value was interpreted as decimal hours instead of hrs:min:sec. The Masked Edit control that is used to accept time edits is hard-wired into the Windows Regional Settings, and will always format time as hrs.mins.secs if a period is defined in Windows as the separator and no action to override this is taken in the program.

The next update (Beta B) will fix this by setting the time separator in the code to ':'. This will not affect the Regional Settings for time used by other programs, just SWMM 5. I should note that a similar thing is done now in the SWMM 5 GUI code for the date separator (a '-' is used) and the decimal separator (a '.' is used). Again, these settings only apply to runs of SWMM 5. The decimal separator is somewhat problematic for folks in countries where a comma is used, particularly if they want to import or cut/paste data into SWMM 5 that has commas in it.

Lewis Rossman
rossman.lewis@epa.gov