The study looked at pollution in urban areas near Taihu Lake in China. They found that even though laws have helped control pollution from factories, runoff from cities is still a big problem. Different types of neighborhoods were studied during rainstorms to see how pollution affected the water. They discovered that runoff from cities made the river water dirty. Some neighborhoods had more pollution in their runoff than others. By holding back some of the runoff, they could make the water cleaner. The amount of pollutants like nitrogen and phosphorus in these urban areas was higher than in other parts of China. This research can help reduce pollution in highly urbanized areas.