The Reuse of Neyshabur Domestic Wastewater Effluent for Agricultural Irrigation

The increasing global population and diminishing freshwater resources have intensified the demand for alternative water sources, particularly in agriculture. The reuse of treated wastewater offers a promising and sustainable solution to mitigate water scarcity in arid and semi-arid regions. This study evaluated the quality of the Neyshabur Wastewater Treatment Plant Effluent (NWTPE) and its suitability for agricultural irrigation, based on Iranian National Standards (INS) and the World Health Organization (WHO) guidelines. The study was designed as a one-year cross-sectional analysis, during which the physical, chemical, and microbiological characteristics of the NWTPE were evaluated against national and international standards for agricultural water reuse. Results indicated that average concentrations of Biological Oxygen Demand (BOD: ۷۸.۷ mg/L) and Chemical Oxygen Demand (COD: ۱۸۲.۱ mg/L) were within acceptable limits for the irrigation of non-food crops. Fecal Coliform (FC) levels remained below ۳۴۰ CFU/۱۰۰ mL, and no Helminth Eggs (HE) were detected, suggesting adequate microbiological safety. However, elevated levels of parameters-including sodium (Na+), chloride (Cl), the Sodium Adsorption Ratio (SAR), and Total Suspended Solids (TSS)-indicate potential risks to soil permeability and long-term salinization. Seasonal variations in the NWTPE quality highlighted the importance of carefully timing reuse. Total Dissolved Solid (TDS) levels peaked during dry months, increasing the risk of osmotic stress in sensitive crops. Correlation analysis revealed a significant association between SAR and Na+ concentration, highlighting concerns about sodicity risks. Overall, the NWTPE met core standards for restricted irrigation applications, such as industrial crops and landscaping. However, episodic exceedances in salinity-related indicators underline the necessity for continuous monitoring and, potentially, the integration of supplementary treatment methods. This study confirms the technical viability of wastewater reuse in arid environments but underscores the need for adaptive, site-specific management to ensure long-term sustainability.

کلیدواژه ها:

Agricultural Irrigation ، Water Scarcity ، Wastewater Reuse ، Water Quality ، Neyshabur City