Abolfazl Hamedani - Department of Civil Engineering, K. N. Toosi University of Technology, Tehran, Iran
Hossein Zarei - Department of Civil Engineering, K. N. Toosi University of Technology, Tehran, Iran

As water scarcity is a global issue and the world population is rising continuously, wastewater reuse is a key method to lower the stress on the water body. Conventional wastewater treatment methods are usually designed to meet local regulations to discharge the effluent to the environment while processes involved, require a considerable amount of electrical power which is usually provided from non-renewable resources. Also waste sludge in high amounts is the other problem which needs extra facilities and budget to be dealt with. Sustainable wastewater treatment systems suggest more environmentally friendly and cost-effective methods that can make the treatment system energy-producing and resource recovering system. On the other hand, nature-based wastewater systems are one of the approaches to sustainability as they are simple, cost-effective, and environmental methods. In the present study, the disadvantages of conventional wastewater treatment methods have been investigated. Then the sustainable treatment methods are examined in detail. Information on how each system works is listed, and the available methods are compared at the end.

sustainable wastewater treatment; nature-based wastewater treatment systems; wetlands; resource recovery