地下水内排对南水北调中线干渠水质的影响

基于MIKE 11模型的水动力模块、对流扩散模块建立南水北调中线输水干渠水质模型,充分考虑了干渠两侧地下水内排段的影响,以京石段为干渠水质模拟示范段,针对内排段水质对干渠水质的风险特征,选取氨氮作为典型污染组分,结合实际工程设计,计算在最不利工况下的内排量,并依此设定情景模拟内排段水质对干渠水质的影响。模拟结果表明,在假定的内排段污染风险达到极大的情况下(水质处于劣Ⅴ类),排入干渠的地下水对干渠水质基本不构成影响。

Impact of groundwater internal discharge on the water quali ty of open channel intheMiddle Route of South2to2North Water Transfer Project

Guar antee of w ater qua lit y in the M iddle Ro ute o f So uth2to2North Wat er Tr ansfer Project is key fo r successful o per a2tion of the project . In this study, a coupling mo del int eg r ating w ater quality and quantity betw een channel w ater and g roundw a2ter along the channel w as developed based on the hydro dy nam ic and advection2diffusion mo dules of MIKE11. The mo del co nsid2er ed the impacts of gr oundw ater internal discharg e sectio n alo ng t he channel and Beijing2Shijiazhuang section was selected as thesimulatio n demonst ratio n sectio n. In terms of the character istics of water quality in the inter nal dischar ge sectio n, NH32N w asselect ed as the ty pica l po llutant compositio n. Acco rding to the actual engineering desig n, water quantity of the inter nal discharg esectio n w as calculated under the most disadvantag e w or king conditions, and the impacts of w ater quality in the internal dis2charg e section on the channel w ere simulated using the scenario analysis. The r esults indicated that there is no impact on thechannel w ater qualit y under the most ser ious scenar io in w hich g ro undw ater inthe inter na l discharg e section is contaminated ver2y serio usly.