Dynamic Analysis of Water Demand; Case Study of Qom City

Water scarcity is now one of the most critical challenges in most countries around the world, especially in Iran. One of the key ways to control and manage this issue is the investigation of the water demand. Qom city has always been encountered with a threat due to its location in the dry area of the country and in the absence of proper management in the near future, there will be serious dangers in this field. The purpose of this thesis is investigation of water demand dynamics from method of system dynamics in Qom city. Dynamic of various variables such as population, water demand, surface water resources, ground water, water supply in this model has been used by Vensim software. The maximum relative difference (%) of this model for estimation of water demand was found to be 7%. The change of birth rate from 4% to 2% resulted in 29% reduction of water demand level in 1405 compared with current trend. . Base on this result, the policy of population control had the most important effect on water demand. The price effect on water demand is negligible, so that, 20% increase of price leaded to 2.04% reduction in level of water demand in 1405 compared with current trend.