Introduction
Increased stormwater runoff from impervious surfaces is a major concern in urban areas (Scholz, 2004) where the sewage systems cannot cope with heavy storms. However, upgrading to a larger system capable of quickly rerouting the water would not only be costly, but would also pose a risk of flooding downstream and reduced efficiency of water treatment installations (White, 2002). Hence, water runoff management has attracted much interest in recent years. In the United States, Stormwater Best Management Practices (BMPs) are primarily designed to lessen the impact of urban development and drainage by increasing stormwater storage areas across a watershed, therefore slowing the flow
of water into a receiving water body, and/or replacing impervious surfaces with permeable areas that allow stormwater infiltration (Carter & Jackson, 2007). Effective management practices include stormwater planting (aboveground planting containers that intercept water diverted from a roof), open channels