嘉定镇是江南古镇,同时又是上海市郊的科学卫星城。城中有十字形河道穿越而过。东西为练祁河,长1.8公里,南北向是横沥河,长2公里。老城外有环状的环城河相接。老镇区的面积为3平方公里。近年来,新居民小区发展很快,而人口集中繁华的老区改造不多,尤其是下水道等市政 Jiading Town is an ancient town in the south of the Yangtze River. It is also a scientific satellite city in the outskirts of Shanghai. There are cross-shaped river crossing the city. Things to practice Qihe, 1.8 km long, north to south Hengli River, 2 km long. Ring outside the old city ring around the river phase. The old town area of ​​3 square kilometers. In recent years, the rapid development of new residential area, and densely populated old areas not much transformation, especially in municipal sewers and other