There is much discussion regarding the effects of urban development on stormwater management, especially the negative effects such as flooding, stream erosion, and increased pollution. An emerging sustainable stormwater management philosophy is Low Impact Development (LID), which seeks to reverse these negative effects by designing infrastructure to mimic natural hydrologic processes such as infiltration. This paper considers several lot level stormwater management controls encouraged by LID using the Environmental Protection Agency''s modeling program SWMM 5.0. The results show that for a typical residential lot in Toronto, Ontario, LID technologies can have a significant positive impact. For example, peak runoff from a 1-inch unit storm was reduced by 57% with the construction of a green roof or when paved areas are replaced with porous paving.