Impact of wastewater on groundwater resources in Sana’a basin, Yemen

Wastewater of Sana’a City is used for irrigation and rejected in Wadi Beni Hwat. To study the potential for contamination, the physicochemical (pH, electrical conductivity (EC), chemical oxygen demand (COD), biological oxygen demand (BOD5), total suspended solid (TSS), K + , Na + , Ca 2+ , Mg 2+ , Cl − , SO 4 2− , NO 3 − , NO 2 − , NH 4 + , PO 4 − , and HCO 3 − ), analysis of 28 samples of groundwater, wastewater, and soil was conducted in different times between 2013 and 2014. The results show that the shallow aquifer presents a high concentration of nitrates, COD, and BOD5. The contamination comes from the wastewater and pesticides used for irrigation.