WWHM-SWMM is a stormwater modeling tool that combines the best hydrology model (HSPF) with the best hydraulics model (SWMM).

WWHM-SWMM is based on the Western Washington Hydraulogy Model with SWMM5 fully integrated. The model is designed to be used anywhere in the US or other countries.

The new Graphical User Interface allows users to easily create models using both HSPF and SWMM elements. Interconnecting elements is simple and intuitive.