Reducing Stormwater Runoff: A Mathematical Model of Green Roof Design

Abstract

Green roofs are one of the most efficient ways to decrease stormwater runoff. Optimizing green roof design helps maximize stormwater infiltration. This paper proposes a water balance model of green roofs and validates it with data measured on the green roof at Milwaukee.

The water balance model proposed in this paper can be programmed using any simulation software, which explains the effects of vegetation coverage, soil porosity and depth, and plant type on stormwater runoff. Stormwater runoff can be reduced by more vegetation coverage, greater soil porosity and depth, and plants with lower internal leaf resistance and larger leaf size.