Micro Drainage is a modeling methodology for analyzing surface and sewer drainage system performance using the best-available information. Micro Drainage analysis models the precipitation flowing from overland system into the minor system through catch basins acting as outlets from major to minor system. This technique models everything from overland cross sections, culverts, inlet / onsite controls, to inlet blockages, and more. Thus, by modeling to such “micro” level, the accuracy of the model will greatly increase, hence producing much more accurate current and post-development conditions.

Micro Drainage is basically a set of tools that aids the user in modeling a dual drainage analysis in SWMM to extreme level of detail. Data accuracy and preparation is extremely important for the model, all the data being fed to the system should be as clean as possible. The software allows for some GIS editing, including internal shape and attribute editing, added external layers (such as aerial photo, roof layer, etc.) that are not mandatory to create the model are not editable.