Hydrological Operation Requirements for Restoration and Improving Water Quality of Al Qurna Marsh


A hydrological routing study for Al Qurna Marsh was carried out to estimate the hydrological state within the marsh for the Present and future conditions of the marsh. The water surface elevation, area and storage within the marsh at the present and for the future conditions were estimated and the effect of uncontrolled outlets on the hydrological and water quality state of the marsh at the present conditions was specified. The salt mass - balance equation was used to estimate the inflow and outflow discharges that required for reducing the effect of evapotranspiration on the water quality and flashing out the accumulated mass of salts and then improving the marsh water quality. This equation was applied on the future conditions of themarsh and inflow and outflow discharges that required for this purposes were estimated. Results of the hydrological routing for the present conditions showed that the maximum water surface area is 785 km2 which occur during October. While it is 431km2 during September and it can not be increased during these months since the outlet of the marsh is uncontrolled. The TDS concentration within the marshincreases during the months of high evapotranspiration although the inflow increases during these months. For the future conditions, the inflow discharges required to sustain the restoration requirements must be increased to decrease the deterioration in the marsh water quality. These discharges increase with the increase in the marsh areaduring the months of high evapotranspiration values.