Feasibility Assessment of Use of Refined Urban Wastewater for Reclamation of Arid Lands (Case study: The Urban Wastewater Treatment Plant of Sabzevar)

One of the methods for water resources development to meet water supply requirements, is the use of treated urban wastewater. In this paper, the feasibility of use of refined urban wastewater of Sabzevar was evaluated. This study was implemented in Dorok desert land located in southwest of Sabzevar over three year(2009- 2011). In order to meet this general objective, the complete randomized block design with three treatments (Haloxylon, Atriplex and Nitraria schober) in 9 replicates per treatment was selected. To evaluate the quality of the effluent, the samples were taken from sewage wastewater treatment plant of Sabzevar and entering water to the collecting reservoir. The samples were analyzed in the laboratory to study the major contaminants based on environmental standards for sewage in Iran. The results of this part of study showed that all evaluated parameters are suitable for irrigation, except for two parameters of Dissolve Oxygen (it was solved by mixing it with seasonal flooding) and coliforms count in the effluent. The results in terms of classifying the quality of wastewater for agriculture and irrigation by Wilcox diagram, showed the class C3-S1, which means relatively suitable class. To evaluate the second objective, areas planted were divided into three sections and each section is divided into three parts (9 repetitions). For evaluation of plant density (percentage of plant), 120m transects was used and the results showed that on average, 67 percent of Haloxylon, 74.3 percent of Atriplex and 90.3% of Nitraria schober have survived. The results are indicators of match effects which are at 1% level meaningful.