The Delineation Adjustment And Protection Study On Huating Lake Reservoir Drinking Water Source Protection Area In Taihu County, Anhui Province

Reasonable delineation and adjustment of the drinking water source protection area can not only effectively protect drinking water sources,achieve the purpose of preventing and controlling drinking water source pollution and ensuring people's health,but also help to coordinate the relationship between water source protection and local social and economic development.At present,analogical empirical method and numerical model method are widely used in the delineation of drinking water source areas.In the water source protection areas which delineated by numerical model method,most of them were rivers and groundwater water sources,but few of them were large lakes and reservoirs water sources.The first delineation of Huating Lake drinking water source protection area was conducted in 2009.The regulations and technical guidelines for the delineation had been revised,and the scope of the secondary protection area was beyond the actual needs of the protection of drinking water sources.In order to explore the way to coordinate environmental protection and social&economic development in the Huating Lake Basin,and to ensure the water safety,this study took the Technical guideline for the delineating source water protection areas(HJ 338-2018)as the basis,combining the MIKE21 numerical model method and analogy empirical method,using ArcGIS technology to research the delineation's adjustment,delimitation,mapping,area verification,rationality analysis of the Huating Lake drinking water source protection area based on the investigation of the current situation of Huating Lake drinking water source.According to the actual situation of Huating Lake Basin,a set of targeted water source protection scheme was proposed,which provided the reference basis for the delineation and protection of similar reservoir water source protection areas.The main research contents and conclusions were as follows:(1)By testing and evaluating the water quality which sampled from the front of the dam(beside the water intake)and the central location of Huating Lake,the current situation of the water quality of Huating Lake was determined as follows:the water quality in the center of the lake met the class III water quality standard,the water quality in front of the dam met the class ? water quality standard according to the Environmental quality standards for surface water(GB 3838-2002),The lake surface as a whole was at medium nutrient level,which was a high-quality water supply source for Taihu County and its surrounding towns.(2)Through the water separation period verification based on MIKE21hydrodynamic and water quality coupling simulation,it was shown that the water quality of Huating Lake Basin fluctuated greatly in the low water period(June).The water quality concentration distribution of TN,TP and DO in this period was predicted according to the change of topography and water level in the study area,the analysis showed that the concentration distribution of TN and TP may be affected by non-point source pollution and mountainous areas'topography,while the concentration distribution of DO may be affected by water temperature.According to the prediction results of concentration distribution,the key and secondary protection areas of drinking water source were delineated.(3)The key,secondary and quasi protection area were also delineated by analogical empirical method.Considerde the general situation of natural environment and the actual social&economic development status of the basin,analogical empirical method and numerical model method were combined,ultimately determined the water sources delineation method was:the key protection area's water range was delineated by numerical model method,and the rest protection areas were delineated by analogical empirical method.(4)Through field research and data collection,and with the support of ArcGIS technology,the newly delineated protection areas were demarcated,mapped,verified in area,and analyzed in terms of rationality.The water area and land area of the Huating Lake key protection area were delineated into 0.45 km~2 and 0.31 km~2,the water area and land area of the secondary protection area were 4.45 km~2 and 15.51 km~2respectively,and the quasi-protection area was 1858.25 km~2.Based on the on-site visits and the analysis results of the pollution load in the basin,the main problems in Huating Lake Basin were identified,and the targeted protection measures were proposed at the same time.