Assessment of New Esna barrage impacts on groundwater and proposed measures

Nile valley quaternary aquifer is in direct hydraulic interaction with Nile River, canals and drains. Therefore, implementation of new Esna barrage leads to enhancement of seepage flow from Nile River toward adjacent agricultural lands, impedance of drainage conditions and increase in the shallow groundwater levels beneath buildings in urban areas. Therefore, Esna city was selected as the study area to assess the impact of the barrage effect on groundwater aquifer and to propose mitigation measures. The most powerful method for studying the problem is developing a groundwater model based on monitored groundwater levels and simulating the effect of the proposed measures. Results indicated that Nile River in reaches upstream the barrage feeds the aquifer. Then, a model is used to test the effect of the mitigation measures on the surrounding settlements. Results also indicated that using cut off drains with depth of 2.5 m is the most effective and safe solution, in terms of direct impact on the buildings without need for operation cost – only maintenance cost will be needed. Also, implementing a sewage network in the city as a long-term solution is recommended.