Iranian Business Management Association International Journal of Resistive Economics 2345-4954 5 2 2017 07 01 Economic Valuation of Water Resources Using the Evaluation And Planning System “Weap”; (Case Study: Masouleh River) 20 31 122199 EN Rahil Rahimi Department of Environmental Engineering, Faculty of Natural Resources, Lahijan Branch, Islamic Azad University, Lahijan, Iran. Leila Ooshaksaraie Department of Environmental Engineering, Faculty of Natural Resources, Lahijan Branch, Islamic Azad University, Lahijan, Iran. Hasan Karimzadegan Ph.D of Environmental Economics Journal Article 2017 02 28 A high amount of water demand nearby Masouleh River in the Guilan province of Iran – in spite of high flow rate of this river – is supplied by Sepidroud Dam and a significant amount is supplied from underground water that finally it leads to the Anzali Wetland.  A part of the surplus water of this river is wasted, evaporated or changed to flood water. WEAP software submits a model for simulation of flow rates and water demand in the future. In the designed model, it was determined that the amount of lack of rural water need will increase from 27.76 million square meter to 32.67, and lack of agricultural water will decrease from 153 million square meter to 96.6, during next 25 years. Additionally, in this research, software efficiency for economic evaluation was studied, based on exciting economic data. The results gained from the designed model indicated that in the economic discussion, benefit rate is 28$ per square meter in 2011 and 29.5 $ in 2035. Through comparing of expenses between different scenarios, the scenario of “change of priority of supply resource of agricultural water need”, submits the minimum amount (24$) and the scenario of “growth population”, submits the maximum amount (29 $) per square meter. https://www.oajre.ir/article_122199_f722b1c4734b352eeb442f7e2a5a5fb5.pdf