This study evaluates the potential of off-grid treated wastewater for crop irrigation in arid regions, focusing on Al-Furaa Regional School in the Negev Desert, Israel. The objectives were to (1) assess the effects of treated wastewater on crop growth and yield, (2) examine the quality of treated wastewater, and (3) explore the suitability of schools as sites for such systems. Coriander (Coriandrum sativum) was cultivated under two irrigation regimes—treated wastewater and freshwater—over a five-week period. Weekly measurements of crown diameter revealed that coriander irrigated with treated wastewater grew faster, averaging 40.8 cm compared to 35.75 cm with freshwater. However, dry biomass yield showed no statistically significant difference between treatments. Water quality analysis indicated partial compliance with Israeli agricultural reuse standards, with elevated levels of ammonia, total nitrogen, sodium, and fecal coliforms. Interviews with Laguna Innovation operators and the school management emphasized the benefits of implementing off-grid systems in school that is improved sanitation, aquifer protection, enhanced water management and environmental education. Despite water quality challenges, the findings demonstrate that treated wastewater can support crop growth like freshwater irrigation thus offering viable solutions for water-scarce and remote areas. With improved treatment processes and monitoring, such systems could contribute to sustainable agriculture. Further research is needed to evaluate effects on different crops and address public health implications.
Keywords: Off-grid, treated wastewater, coriander, irrigation, biomass yield, water management.
