Urban Water Supply And Demand Balance Analysis Based On SWAT And WEAP Models

Water resource is an essential component of socio-economic development and human prosperity.With the continuous growth of society and economy,the people's living standards have gradually improved,China is facing a severe situation of water resources utilization.Water supply and demand balance is a study to eliminate the imbalance between water supply and demand and make them mutually adaptable.It can take various engineering and non-engineering measures without damaging the ecosystem,reducing or even overcoming the impact of water problems on humankind,and is an important means of solving water shortages.The city is the carrier of human life and socio-economic activities.The analysis of urban water supply and demand balance is not only a practical verification of ecological environment productivity theory,but also a reasonable solution to balance the socio-economic development and the natural resources in the face of increasingly tight water resources in cities.It has important practical significance.This study takes Tai'an as the study area and conducts research on the supply side and demand side of urban water resources.On the water supply side,the basic data such as DEM data,land use classification data,soil data,meteorological data,and hydrological data in the study area were used to establish the SWAT model of the Dawen River Basin.On the demand side of urban water resources,mathematical models were used to predict key variables such as population,GDP,effective irrigated area,and number of livestock to establish a WEAP model in Tai'an.Using the SWAT model to drive WEAP model,complete the coupling of distributed hydrological model and integrated water resources management model,and analyze the water supply and demand balance in Tai'an.This study mainly draws the following conclusions.Based on the current water supply and demand conditions in Tai'an,a reference plan was constructed without any new policy or technology and other external factors to interfere,and the water supply and demand balance in Tai'an from 2015 to 2030 was simulated and analyzed.It was found that the urban water supply-demand ratio(total water resources/total water demand)dropped from 1.12 in 2015 to 0.87 in 2030,and the urban water shortage will reach 1.86×10~8m~3 in 2030.It shows that the current water resources of Tai'an can't meet the city's future water requirements.According to the simulation results with reference to the plan,combined with the requirements of socio-economic development and the balance of resources and environment,comprehensively consider the impact of water supply supply side utilization measures and demand side water saving measures on the water supply and demand balance of Tai'an.Analyze the balance of water supply and demand in Tai'an from 2015 to 2030.It was found that the water supply and demand ratios of S3,S4,S5,and S9 plans reached 1.17,1.13,1.11,and 1.09 respectively in 2030,and none of the four plans resulted in a shortage of water demand.Explain that S3,S4,and S5 plans to take any utilization measures at the water supply side,adopt medium efficiency water saving measures at the water demand side,and S9 plan to take efficient utilization measures at the water supply side,adopt some of medium efficiency water saving measures at the water demand side can achieve water supply and demand balance in Tai'an in the future.The water year method in the WEAP model is used to predict the future water resource changes in Tai'an,and the water supply and demand balance in Tai'an will be simulated and analyzed from 2015 to 2030.It was found that the S3 plan that produced the smallest water shortage was an average water shortage of 1.52×10~8m~3 in dry years,and an average water shortage of 5.75×10~8m~3 in very dry years.After adjusting part of the S3 plan's utilization and water-saving measures,the average water shortage in dry years dropped to 0.26×10~8m~3,and the average water shortage rate was 1.48%.In very dry years,the average water shortage decreased to 1.80×10~8m~3,The average water shortage rate was 15.70%.It shows that the capacity of water resources system in Tai'an to cope with special droughts and continuous droughts is weak,and certain water resource utilization and water-saving measures need to be taken on the basis of the S3 plan to cope with drought conditions.This study proposes safeguard measures for water supply and demand balance in Tai'an.On the water supply side,the use of renewable and rainwater resources should be strengthened.On the demand side of water resources,water conservation for residents'living,agricultural irrigation,industry and the tertiary industry should be strengthened.In the case of special drought or continuous drought,emergency measures such as increasing surface water and groundwater extraction,temporary punitive charges for exceeding standard water use,shutting down industrial enterprises that consume large amounts of water,and low benefits should be adopted to ensure social and economic and residential water use.It is not damaged,and the possible damage is minimized.This study explores the analysis method of urban water supply and demand balance,analyzes the water supply and demand balance of Tai'an,and proposes solutions to the problems in the analysis process.It provides directions for the future development of the city from the perspective of water resources and promotes urban society The balance between economic development and natural resources is of great practical significance.