I just wanted to clarify some issues raised by the last two SWMM 5 beta posters:

1. Neither we at EPA and CDM, nor many other testers have had any problem with setting the computational time steps in SWMM 5 or in running the example data sets. The routing time step in Example 3 of the beta test package is 30 seconds, not 30 hours. Giovanni, if you could be more precise about your problem, send it in to swmmqa@epa.gov and we'll try to debug it.

2. Rainfall time series are read correctly as continuous values, over the time interval specified for the Rain Gage to which the time series belongs. That is, if Rain Gage RG1 has a time interval of 15 minutes and uses time series TS1, then each value entered for TS1 applies over a 15 minute interval. We have tested many rainfall-runoff examples (under US units) and everything is working as it should. (There is a bug in the conversion factor for metric rainfall units of mm/hr to feet/sec). What might be confusing is that the graph displayed in the Time Series Editor shows the time series as point values connected by straight lines, rather than a "step" function as one would expect for rainfall. This is strictly a display issue, and we'll try to find some way to make things look clearer. Noel, if you think you have a data set that's giving nonsensical results, then please send it in to swmmqa@epa.gov so we can check it out.

As I write this the first batch of SWMM 5 bugs are being posted to our web site. We are encouraged so far by the number of people who have taken the time to check things out and we expect more will do so as they find the time and as the robustness of the beta version improves. Thanks for your feedback.

Lewis Rossman
rossman.lewis@epa.gov