Municipal wastewater treatment in Iran: current situation, barriers, and future policies

With population and economy growth, water usage, wastewater generation and treatment, treatment plants capacity and innovation ability in Iran have increased dramatically in the last decades. Currently, Iran is in the grip of severe water scarcity, with renewable water availability of less than 1700 m3/capita/yr. Total municipal wastewater generated in Iran is 4.61 billion m3/yr out of which only 42% is treated. The conventional activated sludge process accounted for the largest share (>60%) in municipal wastewater treatment in Iran. The treatment plants operational costs usually amount up to 0.2 US $/m3 wastewater. About 55% of treated municipal effluent is reused in Iran, with an emphasis on the agricultural sector. The electricity consumption in municipal wastewater treatment facilities amounts for 0.1% (241 million kWh/yr) of the total electricity consumption of the country. Meanwhile, the current laws and policies are sometimes inefficient or do not prompt the ideal outcomes. Thus, the present study provides an overview of municipal wastewater treatment in Iran by describing the current situation and collecting data from 68 treatment plants, and defining key barriers and future policies needs towards Iran's sustainable municipal wastewater management (up to 2040). Here, the opinions of 50 experts from the governmental sector, industry division, and faculty members were surveyed through the meetings of the technical and steering committee. Overall, sustainable municipal wastewater management in Iran would be obtained by developing water resources, increasing the population covered by wastewater facilities (90%), improving effluent discharge standards, and lowering energy usage to 0.45 kWh/m3 wastewater.