Study On The Scheme System Of Intermediate Water Barrier And Dissipation In The Lower Reaches Of The Guangfu River

The South-to-North Water Transfer Project is the largest water diversion project in the world up to now,including the East,Middle and West Routes.The East Route Water Transfer Project mainly uses Jiangsu,Shandong and Hebei Provinces to supply water to North China.As the first water storage and regulation Lake in Shandong Province after the East Route Project of South-to-North Water Transfer,the water quality of Nansi Lake is directly related to the water quality of water transfer.As one of the main tributaries of Nansi Lake,the Guangfu River has an important impact on the water quality of water diversion.At the same time,because the entrance of the Guangfu River is located at the lowest reaches of the Nansi Lake and adjacent to the Liangji Canal,the main water transmission line of the South-to-North Water Transfer Project,its unique geographical location highlights the importance of the water quality problem of the Guangfu River.In order to ensure the water quality of the South-to-North Water Transfer Project,the Shandong Provincial Government has constructed 21 interception and storage diversion projects,of which 2 are located on the Guangfu River and its tributaries.The construction and operation of the interception and storage diversion project ensured that the water quality of the Guangfu River into the Lake reached the standard,and improved the water quality of the water diversion to a certain extent,but the problem has not been solved thoroughly.In this paper,taking the downstream of the Guangfu River in Ji Ning City as the research object,focusing on the goal of"guaranteeing the water quality of the Guangfu River into the lake and improving the water environment quality",a new middle water barrier and absorption scheme system is studied on the basis of the original project,and the following achievements are achieved:(1)In view of the current situation and problems of water environment in the study area,the general idea of"barrier and absorption"is put forward,and the analysis and calculation of water quantity and quality in the study area and the research of water purification technology are carried out.Based on this,a new technical scheme of intermediate water barrier and absorption in the study area is put forward,which can be used to improve the existing water environment quality in the study area and ensure the water quality of the Huafu River estuary to reach the standard.(2)Based on MIKE 11,a one-dimensional hydrodynamic-water quality coupling model is established,and the scheme is simulated and analyzed.According to the simulation results,the above schemes can ensure the water quality of the lake to meet the discharge standards and improve the water environment quality of the study area.At the same time,the pollutant reduction and wetland scale of different schemes are determined according to the simulation results.(3)Considering the project cost comprehensively,and focusing on the goal of ensuring water transfer safety and improving the water environment quality of the study area,the evaluation index system of reclaimed water barrier and absorption scheme is constructed.Based on the theory of engineering fuzzy set,a variable fuzzy evaluation model is established to evaluate and optimize the scheme.According to the evaluation results of the model,the above schemes are arranged from large to small according to their comprehensive benefits as follows:scheme 6,scheme 5,scheme 1,scheme 2,scheme 3 and scheme 4.Thus,scheme 6 is determined as a technical scheme to ensure the safety of water transfer and improve the quality of water environment in the study area.