The researchers evaluated the performance of wastewater stabilization ponds in Arak, Iran, to improve their operation. They found that the effluent from certain ponds met Iranian standards for agricultural reuse, suggesting upgrades to increase treatment capacity. In Module 1, the primary facultative ponds had compliant BOD5 and COD levels, allowing for conversion of secondary ponds. In Module 2, the secondary facultative pond met standards, indicating potential upgrades to improve treated wastewater quality and quantity.