Research on reservoir emergency regulation for treatment of sudden water pollution accident in Danjiangkou-Xiangyang reach of Hanjiang River

In order to reasonably cope with the sudden water pollution accident in mid-lower area of Hanjiang River,effective emergency plan should be established. By two-dimensional hydrodynamic and water quality model,the pollutant dilution and mixing effectiveness in Danjiangkou-Xiangyang reach of Hanjiang River by outflow from Danjiangkou Reservoir under different regulation modes are analyzed when a sudden pollution accident occurs in different sites,and the feasibility and effectiveness of emergency regulation of Danjiangkou Reservoir are discussed. The analysis results show that short-term and larger discharge operation of the reservoir is more effective than that of long-term and smaller discharge operation; for farther river reach from the reservoir,the pollutant dilution effectiveness by outflow from Danjiangkou reservoir with emergency regulation is not significant while for the upstream river reach of Wanfuzhou Hydropower Station,the pollutant dilution effectiveness is satisfactory.