High water table levels presenting hazards to crop growth were measured at field sites in upper, middle, and lower Egypt. Water table contribution to evapotranspiration was significant at each site. A water balance model of the water table aquifer was used to predict the effect of various interventions on water table levels. Desirable lower water table levels could not be maintained through on-farm irrigation efficiency improvement, which included lining of on-farm channels while using surface irrigation methods. Branch, distributary, and private canal lining would have negligible effect on water table levels. However, increasing drainage outflows could maintain desirable water table levels. Corresponding increases in required water deliveries would be expected. (Author abstract).