Water resources assessment at El-Arish area, using remote sensing and GIS, North Sinai, Egypt

This research aims at to analyse the pattern and rate of shoreline changes at the El-Arish area during the period 1984-2006, which represents the time at which the El-Arish harbour has affected along the coastline. Detecting salinity distribution of the ground water is the second objective of this study. The enhanced Landsat Thematic Mapper images utilised in this study were geometrically corrected. GIS techniques were used to produce vector maps for El-Arish coastline positions and estimate shoreline displacement during the last two decades. The measured shoreline changes derived from remote sensing data indicate accretion along the western coast of El-Arish harbour with +160 m/22 yr, at a rate of +8 m/yr. However, neighbour shore is suffering from erosion with -80 m/22 yr (-4 m/yr). Downdrift erosion occurred along the eastern coast of El-Arish harbour with -140 m/22 yr, at a rate of -7 m/yr. Physical and chemical properties of the El-Arish groundwater are analysed in 48 groundwater samples collected from pumping wells discharged from the Quaternary aquifer during July 2006. Assessment maps constructed by the integrated GIS techniques indicate that, eroded beach was observed at the area subjected high salinity ground water. Two main factors controlling salt water intrusion at El-Arish area are recognized, including the concentration of pumping wells which enhanced upward leakage of saline water from deeper formation and coastal erosion created by natural and human factors. This research indicates significant positive relationship between the groundwater salinity problem and coastal erosion at El-Arish area.