Chung-Ho city is located in the southwest of Taipei basin. The whole area is like a piece of begonia, having a sharp point in the south and becoming broad in the north The alluvial plain in the north token possession half of the whole area. In the period of Taipei lake in the history of geology the lake was si1ted up gradually. The weather in this area is rather warm and rainfall is abundant especially from April to September. However, flood is the most serious environmental hazard.