There is a wide range of applications of DDSWMM. The primary application of DDSWMM would be for the design of new urban drainage systems, with due consideration of minor as well as rare rainfall events. This would include sizing of sewers, analysis of inlet control requirements, determination of flows and flow depth in the major system network, design/analysis of detention storage facilities for runoff control, etc.

The overlwhelming applications of DDSWMM to date, however, have been for the analysis/evaluation of existing urban drainage systems, including areas which were not designed according to the dual drainage principle, and the design of relief measures for both the minor and the major systems, through a combination of DDSWMM and an interface with the EXTRAN model.