Water resources allocation and harmony evaluation - case of uncertain Bi-level planning

With intensifying imbalance between supply and demand of water resources, it is essential to optimize models of allocation for water resources, in line with economic development, population growth and urban expansion. Interval Fuzzy Credibility Constrained Bi-level Programming (IFCBP) was developed to optimize allocation of water resources; harmonious evaluation method was used to quantify harmony degree of water resources-economic social-environment system before and after configuration (current year and planning year). In the model interval values and fuzzy sets were used to process uncertain information to plan water resource allocation at the Henan section of the Middle Route of the South-to-North Water Transfer Project, four water distribution schemes with different credibility (λ=0.7, 0.8, 0.9, 1.0) were considered. Level of harmony for water, economic, social and environmental systems in 2016, 2020, 2025 and 2030 was evaluated. Interval-fuzzy double uncertainty in IFCBP model was found to lead to changes in water resource allocation, pollutant discharge, and system benefits. Two-layer model better balanced conflict between system emissions and economic benefit. This work could help decision makers to resolve conflicts between water demand, economic goals, and ecological improvements.