Monitoring of Water Quality for Agriculture Purposes Using High Resolution Images (ASTER): A Case Study from Egypt

Life of Egypt is substantially linked to the Nile River. The Nile River is the principal source of water in Egypt which is used for purposes such as agriculture, drinking, electricity generation and industry. The Water Quality Index (WQI) is a valuable and simple tool for announcing and explaining massive dataobtained from any body of water. Remote sensing can be a useful tool in the water quality monitoring. WQI is applied, in thispaper, to evaluate suitability of Nile water for irrigation usage, in Rosetta River Nile branch, El-Beheira governorate, Egypt. Water samples were collected from six various sites about 65 km stretch along Rosetta River Nile branch at almost equal distances, starting from Kafr El-Zayat city to Idfina Barrage. Polyethylene plastic bottles (1 Liter capacity) were used to collect water samples. Samples were assessed for eight (8) Chemical parameters, namely pH, electrical conductivity, Sodium, Potassium, Calcium, Magnesium, Bicarbonate and Chlorides. The regression analysis is used to investigate the correlation between WQI and remote sensing data (ASTER images). The results showed that the water quality index were mostly good for irrigation purposes according to FAO guidelines (WQI values between 50- 100), except for site 1 which had a poor class (WQI values between 100-200) because of the artificial pollution at it. The electrical conductivity and sodium concentration were the most important characteristics affecting the calculated water quality index of the study area. Band 1 of ASTER images showed the highest correlation coefficient with WQI (R^2 = 0.86) according to logarithmic regression analysis.