A series of projects have been carried out to improve the city's water quality. In the summer of 2007, there was an outbreak of large blue-green algae in Taihu Lake, China's third-largest freshwater lake, which led to black and odorous water. Wuxi's efforts to tackle Taihu Lake pollution over the past several years have set a national example. The amount of silt that the city has cleared accounts for 70 percent of the total in Jiangsu province. [Photo by Yang Weixing/wxrb.com]