《资治通鉴·汉纪·汉纪二十五》
洪水时常到来，又走了，淤泥沉积成为肥沃的土壤，人民在上面耕种，或许赶上很久都没有发生水灾，于是陆续在这里兴建住宅，遂成村落。若洪水经常泛滥成灾，漂没田宅人畜，为了自救，就把堤防修筑得更高、更多，然后把城镇稍作迁移，排除积水，居住下来。
时至而去，则填淤肥美，民耕田之；或久无害，稍筑宫宅，遂成聚落；大水时至，漂没，则更起堤防以自救，稍去其城郭，排水泽而居之，湛溺自其宜也。
Floods would come and go often, and the silt they deposited became fertile soil, which people farmed. Sometimes, there would be no floods for a long time, so people gradually built houses there, which eventually became villages. If floods occurred frequently and destroyed fields, houses, and livestock, people would build the embankments higher and in greater numbers to save themselves. They would then move their towns slightly, drain the accumulated water, and settle down.