Lake Nubia (LN) is the Sudanese portion of Aswan High Dam Lake (AHDL). This
paper aims to detect the better technique for extraction of the water surface of LN.
Eight techniques are tested using Landsat ETM+ image and their performances in
extracting the surface water area are evaluated. The eight techniques include
Automated Water Extraction Index [AWEI], Normalized Difference Moisture
Index [NDMI], Normalized Difference Water Index [NDWI], Modified
Normalized Difference Water Index [MNDWI], Normalized Difference Vegetation
Index [NDVI], Water Ratio Index [WRI], Supervised and Unsupervised image
classification techniques. The results indicate the effectiveness and superiority of
the unsupervised technique, as it gave the highest overall accuracy (about 97.23%)
and the lowest absolute error. It is recommended to apply this technique to
efficiently monitor changes in the surface water areas of the lakes using Landsat
ETM+ data