清中后期清政府保运体系中的淮水入海入江选择

The Choice of the Huai River Entering the Sea and the Yangtze River in the Transportation Guarantee System of the Qing Government in the Middle and Late Qing Dynasty

明末清初,淮水大部分在清口入黄,下游水量较少。清代中期以后,清口区域泥沙逐年沉淀淤积,黄河堤和洪泽湖湖底不断抬高,这使得淮水开始在汛期更多地从山盱五坝下泄高宝诸湖,然后进入归海与入江通道。早期的水灾并不严重时,里运河北部没有淤高,泄水面较广。然而,随着北部的淤高,泄水区主要集中在车逻坝一带。康熙乾隆时期,官方一方面维持高堰,一方面开拓入江方向的洪水排泄。不得已时,官方仍开车逻坝泄水。道光年间,官方每年长期闭御黄坝,淮水几乎处于全入运状态。运河因着黄水入运而不断被淤高,高堰因着湖蓄加强和黄河水入湖而被不断加高,大水时入江与入海水量更加增长,几乎达到泄水量的限制,盐场也常受水灾。泄水难下,官方常常叫里下河地区承受最终的水灾以保运河畅通。这其间归海与归江的技术选择涉及水环境变化,涉及一系列的工程,也涉及清政府的运河策略。

In the late Ming Dynasty and early Qing Dynasty,most of the Huai River flows into the Yellow River at Qingkou,with less water in the downstream.After the middle of the Qing Dynasty,the sediment in Qingkou area deposited year by year,and the bottom of the Yellow River embankment and Hongze Lake kept rising.During the flood season,the Huai River discharged more from Shanyu five dams into lakes in Gaoyou and Baoyeng county,and then into the channel to the sea and into the Yangtze river.When the early flood was not serious,there was no so much siltation in the north of the Li canal and the discharge area was wide.However,with the siltation in the north,the discharge area is mainly concentrated in the area of Cheluo dam.During the reign of Emperor Kangxi and Emperor Qianlong,the government maintained the Caoyan on one hand,diverted the flood into the river on the other hand.When there is no alternative,officials still open Cheluo dam to release water.During the Daoguang period,the government closed the Yellow River dam for a long time every year,and the Huai River was almost all in the great canal.The canal is constantly silted up by the yellow water,and the Caoyan was continuously raised due to the strengthening of Lake storage and the entry of the Yellow River into the lake.During the flood,the water entering the Yangtze River and sea increased even more,almost reaching the limit of water discharge,and the salt farm was often affected by floods.When it is difficult to discharge water,officials often ask Lixia river area to bear the final flood to keep the canal unblocked.During this period,the technical choice of returning to the sea and returning to the Yangtze River involves the change of water environment,a series of projects and the canal strategy of the government of Qing dynasty.