Sustainable reuse of hemodialysis reject water for potato farming: a large-scale feasibility study in Morocco.

Background: Hemodialysis consumes huge volumes of water and produces large quantities of wastewater.

Aim: This study explored how to sustainably reuse hemodialysis reject water for large-scale potato farming in Morocco. With the increasing demand for water resources in agriculture and the challenges posed by water scarcity, this project explored the potential benefits of using this wastewater, its impact on potato yields, and the possible economic aspects.

Methods: The AquaCrop-FAO model was used to simulate potato growth in a hot, semi-arid area with drip irrigation. The model was calibrated using data concerning five potato varieties. Validation included information from experimental studies in similar climates and soil conditions.

Results: Morocco produces about 1.1 million cubic meters of hemodialysis reject water each year. The simulated potato yield is estimated at 29.37-47.67 t/ha depending on the potato variety (- 8.8 < Dev < - 2.5). The model revealed a good fit for potato yield with 0.941 ≤ R2 ≤ 0.998, 1.345 ≤ RMSE ≤ 3.324, 0.05 ≤ NRMSE ≤ 0.092, 0.443 ≤ EF ≤ 0.887 and 0.855 ≤ d ≤ 0.974. Cost evaluation showed that using reject water in agriculture could save about $638,000 USD each year in water costs. The financial benefit from potato farming with this type of water could reach $7000 to $10,000 USD per hectare, depending on the farm size, with an overall gross benefit from this water of $5-9 million USD per year.

Conclusion: Reusing hemodialysis wastewater could save water and create extra income for dialysis facilities.