عنوان مقاله [English]
Due to the problem of water scarcity in the country, Water supply is very important. In such circumstances wastewater reuse can be considered as one of the ways to overcome the problem of dehydration.Therefore, the use of unconventional water resources (including wastewater) in our country is becoming increasingly important. The use of such waters can provide water to the urban green space, cultivate crops that are not consumed raw and artificial nutrition for those with severe groundwater levels, a strategic policy to reduce the pressure on conventional water resources. Application of wastewater as a permanent source of water in agriculture in addition to supplying part of the water needs of this sector also saves and conserves existing water resources. In addition, the presence of plant nutrients in wastewater treatment plants reduces the use of chemical fertilizers and consequently the environmental impact of their use. In this study, considering the present population and predicting its growing trend until 2030 in Mashhad, we were able to estimate the water demand of the city. Taking into account the amount of consumption, the amount of wastewater that enters the treatment plants in the city and is discharged into the effluent was estimated. Also the volume of effluent for storage and its allocation for different purposes was estimated. According to information and surveys, it was concluded that increasing the share of water in the drinking and sanitation sector would inevitably lead to a decline in agricultural arable water. Wastewater can offset some of the decline in the share of agriculture.