Abstract: Water resources play an irreplaceable role in maintaining ecological environment as well as economic and social development. Quantified research and assessment on the value of water resources, on one hand, offers theoretical support for governments in formulating policies, and on the other, promotes the stable and healthy development of regional social economy. The water resources value in Mianyang City was assessed comprehensively as a case study based on fuzzy analytic hierarchy process (FAHP). An index system involving 14 indicators covering water quality, water quantity, social economy, population, and ecological environment was constructed; weights of the indicators were calculated using both subjective and objective weighting methods. Among criterion layer factors that affect the water resources value in Mianyang, water quantity boasts the largest weight, followed by ecological environment, social economy, population, and water quality in sequence; among index layer factors, total water supply has the largest weight, followed by water resources per capita and reuse rate of industrial water in sequence. The fuzzy comprehensive index of water resource value in Mianyang is 2.37, implying that the water resources value in Mianyang ranks above middle. The price of water resources assets had been on the rise in general from 2014 to 2018, reaching 4.97 yuan/m³, which is 2.6 times the current water price for residents (1.91 yuan/m³). And water cost occupies 0.74% of residents’ income, far below the affordable water cost index, which is 1.19%, accounting for the rationality of raising the price of water resources properly. Nevertheless, the overall water resources value in Mianyang had shown a downward trend year by year during 2014-2018, mainly due to the decrease of water resources amount surpassing the growth of unit water resources value. Government should pay attention to the causes of water resources decline, and put forward future control measures to maintain the sustainable development of local water resources.

Key words: water resources, value assessment, fuzzy analytic hierarchy process, price of water resources, water resources amount, Mianyang City