Abstract: This paper is to discuss quantitatively several issues in urban water resources management, which becomes more important than ever before, and mainly focuses on two aspects: water saving potential and comprehensive evaluation. Water use in urban area is divided into two main components: domestic and industrial use. For industrial water use, the policy of using a dynamic standard that is assumed to decrease linearly or nonlinearly with time has been proposed and thus the potential can be estimated by calculating the difference of the standard and actual water use. It is found that the amount of yearly domestic water use per capita ( RL in lper capita) has related to some natural, social and economic factors of urban area, such as population ( J in 10 4 person), temperature ( AT in ℃) and etc. The relation coefficients between RL and AT , W and K are close to 0.9 for the cities with population more than 1 million. Therefore, hypothetical standards of RL for urban domestic water use of any population scale has been suggested by creating a multiple linear relationship between RL and the above pertinent factors with stepwise regression method. The hypothetical RL for cities with population more than 1 million is given as an example with the following equation:RL=4.09 E-02 +1.38^*AT+1.78 E-02^*W+2.06^*G+1.62 E-02^*KAfterwards water saving potential for domestic use can easily be calculated following the same procedure as that for industrial use. There are in general many methods to evaluate water resources management, such as cost/benefit. Waste discharge and its quality should also be considered in carrying out evaluation for industrial water use. Fuzzy method has been used in this study to evaluate water management for industrial purposes by employing multiple indices such as water reusing rate, COD per ten thousand tons of sewage, fresh water consumption and discharge per ten thousand yuan (RMB). The Bronze Processing Factory of Luoyang city in Henan Province has been selected as a case study to show the adaptability of this method. The percentage of any three predefined management levels for any factory can be calculated (total percentage in 100%) and the comparisons among these factories can be accomplished easily.

Key words: water saving potential, comprehensive evaluation, water resources management