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截至1985年底不完全统计,我省主要河流河道内存在严重阻水围垸109处,占去滩地面积约300平方公里,大大缩小了河道有效行洪范围。此外,一些被认为行洪影响较小的围垸,原来中、高水可行洪、滞洪的,因垸堤不断加高,现在已基本上失去了应有的作用。由于自然演变及围湖、围滩等人类活动的影响,长江中游干流除局部河段外,均呈现年最高水位与年平均水位差值、年最大流量与年平均流量差值增大的趋势,越往下游,这种趋势越明显,洪峰的峰型已正由“矮胖型”向“高
As of the end of 1985 incomplete statistics, the main rivers in our province there are serious water blocking embankment 109, accounting for an area of about 300 square kilometers of beach, greatly reducing the scope of the effective river flood. In addition, some embankments, which are considered to have less impact on flood discharge, have turned out to be capable of doing floods and delaying floods in the middle and high waters. As the embankment has been continuously raised, it has basically lost its due role now. Due to the natural evolution and the influence of human activities such as the surrounding lake and Wai Beach, the difference between the annual maximum water level and the annual average water level of the main stream in the middle reaches of the Yangtze River, except for some sections in the middle reaches of the Yangtze River, tends to increase the difference between the annual maximum flow rate and the annual average flow rate, The more downstream, the more obvious this trend, peak peak has been from “short type” to "high