Assessment of Environmental Impact On, Wadi El-Natrun Depression Lakes Water, Egypt

Assessment of environmental Impact was established to provide and evaluated the background picture of water quality of Wadi El-Natrun depression Lakes water. Physico-chemical characteristics (air and water temperatures, electrical conductivity (EC), total solids (TS), total dissolved solids (TDS), total suspended solids (TSS), salinity, pH, dissolved oxygen (DO), chemical oxygen demand (COD), CO , HCO , 3 3 -Cl , SO , Na , K , Ca , Mg , NO , NO , NH , PO , total phosphorus (TP) and SiO ) were measured and used 2+ + 2+ 2+ 34 2 3 3 4 2 as indicators to evaluate the water quality of lakes. Results indicated that the salinity ranged between 20-400‰ (hypersalin water). EC 88000-201000 μS/cm. TS, TDS and TSS are very high levels. pH values were found to be in the alkaline side 9.12-9.84. and HCO -concentrations are very high and ranged between 3000-12000 and 3 1330-6480 mg/l, respectively. SO -and Cl-are very high concentrations. Na and K are more concentrations than 4 + + Ca and Mg . DO was near to depletion. COD is slightly high concentrations. The nutrient salts, NO , NO -are 2+ 2+ 2 3 not detected during all investigation seasons. NH was ranged between 0.03-0.514 mg/l. PO -and TP were high 3 4 concentrations during all seasons except for autumn. SiO was ranged between 0.7-2.25 mg/l during autumn / 2 summer and not detected during winter / spring. It was concluded that Wadi El-Natrun depression lakes are a unique aquatic ecosystem among saline lakes due to the hyper saline and alkaline waters.