Recent geodetic and oceanographic MSL studies have shown that neither the sea levels nor the land are permanent with respect to time variations. The data analysis of tide gauges produces ‘relative’ sea level changes. However, using tide gauge data alone, it is impossible to distinguish between any true sea level variation and any changes in ground level at a tide gauge site. GPS monitoring can be used to decouple vertical land movements from change in relative MSL, so that tide gauge can provide estimates of changes in absolute MSL. In order to monitor “absolute” changes in sea level, the rates of any vertical land movements at a tide gauge must be determined and subtracted from the resulting rate of tide records [e.g. IPCC, 2001 and Bingley et al, 2000]. Consequently, a sea level monitoring system has been installed at Alexandria tide gauge site containing a GPS receiver as a geodetic monitoring technique to perform this task.