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Representative water samples were collected from different eases in the western desert of Egypt to examine characteristics of Egyptian groundwater. Chemical data recognized two basic groundwater types; alkali bicarbonate and alkali chloride, where sodium has the highest concentration. For each region the median SD, delta(18)O and ionic strength of water calculated from their chemical analyses are recorded and plotted.

Generally, the results of isotopic content measurements of the groundwaters from the different eases in the western desert indicate the fossile origin of these waters. The values of delta D and delta(18)O of the western desert eases' waters are characteristic of old paleowaters from the Nubian sand aquifer. Modern sparse rainfall data suggest that any precipitation will exhibit moderate to large positive isotopic content enrichments and cannot be a source for these waters. They have been in no connection with the Nile water, moreover the change in isotopic composition is due to evaporation which is now ineffective at deeper levels.