In this research, they looked into using different methods like green roofs, rain gardens, and permeable pavement to control stormwater in urban areas. They used a computer model called WWHM4 to analyze how these methods work in Philadelphia and Seattle. They found that these methods can help reduce stormwater runoff, but there are some factors like soil type and seasonal rainfall that need to be considered to make them more effective. The study shows that using these methods can make a difference in managing stormwater.