新孟河延伸拓浚工程对长江水环境影响研究

新孟河延伸拓浚工程是国务院批复安排实施的重要引排工程之一。工程实施后在流域上游开辟引江济太的第二通道,改善太湖西部沿岸及西北部湖湾水流条件,但同时新孟河排水也会对长江水环境造成一定不利影响。通过采用MIKE21软件建立长江下游某一河段的二维水流水质模型,重点研究了新孟河排水对长江以及下游水厂水环境的影响。研究结果表明,工程排水对长江水环境的不利影响主要局限在入江口附近区域,影响程度总体较小。但工程实施后太湖仍不能达到《水环境总体方案》确定的水质治理目标要求。建议在实施过程中,加大治理区域污染源力度,从而减小新孟河排水对入江口区域影响。

Research on influence of Xinmeng River dredging and extending project on water environment of Yangtze River

Xinmeng River dredging and extending project is one of the important drainage projects approved by the State Coun-cil. Its main task is to cleave a second channel in upstream Xinmeng River for the water diversion from Yangtze River to Taihu Lake, which will improve the flow condition of west coast and north-west area of Taihu Lake, but generate negative effects on the water environment of Yangtze River. A two-dimensional flow-pollutant simulation model was established based on MIKE21 to analyze the impact of the drainage project on water environment of Yangtze River and downstream waterworks. The result shows that the adverse effect mainly concentrates in the estuary of Xinmeng River and the impact is slight in general. However, the wa-ter quality still can not meet the requirements of Comprehensive Management Plan of Water Environment in Taihu Lake Basin af-ter the project. Thus, it is advisable to mitigate the impact of the drainage project on the estuary region by strengthening local pollution control.