Comprehensive evaluation of urban water supply security based on the VIKOR-TOPSIS method

To determine the security status of urban water supplies, a comprehensive evaluation model of urban water supply security based on the VIKOR and TOPSIS models is proposed. The comprehensive evaluation value K is obtained as the evaluation result, and the larger K is, the higher the safety of the urban water supply. The results show that the security of the water supply in Tianjin increased from 0.2300 in 2015 to 0.8026 in 2018. Although it slightly decreased to 0.5439 in 2019, it was still at a high level and increased to 0.7508 in 2020. The urban water transmission and distribution status, the service level of the water supply industry, and the status of sewage treatment play positive roles in affecting the safety of the water supply in Tianjin, and the status of urban water sources and the urban water use status are the main factors that reduced the safety of the urban water supply. According to the results of an obstacle degree model and the actual conditions in the study area, it is suggested that Tianjin should continue to focus on the development of water resources and the utilization of unconventional water sources and actively promote the construction of a water-saving society.