Water and salt balance model of Lake Qaroun, Egypt

A model for estimating monthly and annual water and salinity levels of Lake Qaroun was developed using the mass balance concept. The model can assess the effects of various drainage water disposal options. The water and salin ity levels are estimated from drainage water disposal rates, drainage water salinities, as well as evaporation rates. The model simulations were checked against the measured water and salinity levels from 1980-1996. Water level predictions by the model generally agree d with measured values. The monthly modelling efficiency (EF) ranged from 0 .58 to 0.93. On an annual basis, EF was 0.88. With salinity measurements, t he computer model LQR produced reliable results in terms of annual predicti on (EF=0.5), but was in poor agreement (-8.2<EF<0.53) with lake salinity me asurements done on a monthly basis.