基于WASP的湖州市环太湖河网区水质管理模式

为保障清水入湖,以我国富营养化最为严重的淡水湖泊之一——太湖为例,建立了基于水体纳污能力的流域水环境管理模式.同时,针对河网地区水流往复性特点,以水质分析模拟程序(WASP7.3)模型为基础估算了湖州市环太湖河道COD和氨氮的水环境容量,并建立了综合点源和非点源的COD、氨氮日最大排污量(TMDL)管理模式.结果表明,在90%水文保证率下,研究区域水体环境容量CODCr为30153.4kg·d-1,氨氮为5112.4kg·d-1;按照区域2005年排污状况,未达标河段的COD最高削减率达到70%,氨氮最高削减率达到87.5%,才能满足整个流域水体功能要求.

Regional management strategy integrated with WASP model on water quality for river-network plain located in Huzhou District,Taihu Lake Basin

The frequent outbreaks of water eutrophication in Taihu Lake are regarded as one of the most troublesome environmental issues in Southeast China.Based on the water's potential capacity to accept pollutant loads,a watershed-scale environmental management system was established to ensure that clean water enters Taihu Lake.Considering the complexity of the hydrological regimes operating within the river-network plain,the capacities of the water environment for loads of COD_Cr and ammonium nitrogen were estimated using the WASP_7.3 model(Water Quality Analysis Simulation Program,Version 7.3),and a comprehensive TMDL(Total Maximum Daily Loads) system in charge of point and non-point source pollution was developed for management of COD_Cr and ammonium nitrogen.Data analysis showed that water environmental capacity for COD_Cr and ammonia nitrogen loads were up to 30153.4 kg·d^-1 and 5112.4 kg·d^-1 respectively under the assumption of 90% hydrological guarantee.According to the regional pollutant discharge in 2005,the maximum reduction rates of COD_Cr and ammonia nitrogen must reach 70% and 87.5% for river sections that exceed the criteria in order to meet the requirements of the environmental function of the watershed.