Irrigation with Treated Domestic Wastewater: Challenges and Opportunities

Regarding the lack of water resources, the reduction of annual rainfall and the excessive growth of the population and the expansion of industry and agriculture, the use of recycled water is in fact one of the solutions to the water scarcity crisis, which is essential and inevitable. Irrigation treatments were: 1- Application of treated wastewater only 2-3times irrigation with wastewater, then use of well water 3- Irrigation with wastewater and Well water respectively 4-One irrigation with wastewater and three times with well water 5-Well water application and 6-Irrigation with well water + chemical fertilizers. The research was carried out in Austan Ghods agricultural farm in Mashhad for one year harvested. The soil texture was silty loam. The results showed that the yield of rapeseed was significantly higher in treatments that were irrigated with more treating wastewater than those treated with less treating wastewater. In fact, treatments that were irrigated with more wastewater, due to the presence of food in irrigation water, were more effective than other treatments. The amount of heavy metals, soil salinity, nitrogen percentage, absorbed phosphorus and organic matter in irrigation treatments showed a slight increase, but was not significant at 5% level. This gradual increase of the elements in the soil can be considered as a major challenge in the use of long-term refined wastewater. Opportunities from irrigation using wastewater include: tackling the problem of water scarcity, preventing pollution of the environment and surface and underground water resources, increasing the durability of high quality water resources, increasing product yield, saving on consumption expenditure chemical fertilizers and development of aquatic areas.