الفهرس 
Problem StatementOnly 14 pages are availabe for public view
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Abstract
The reuse of large amount of agricultural drainage water, with low cost improvement, in irrigation becomes a strategic policy in Egypt. However, the agricultural drainage systems currently suffer from the increase of pollution levels caused by the excessive use of fertilizers and pesticides in irrigation water and the discharges of untreated domestic and industrial wastewater. Bahr Hadus drainage system, which is of special importance as it contributes about 20% of the irrigation water capacity of El-Salam Canal, was considered as a case study representing a polluted drainage system in the Nile Delta.
The study proposed new interventions to improve the water quality in Bahr Hadus drainage system. A one-dimensional water quality model using the public QUAL2K program was developed, calibrated and validated for Hadus drainage system. The model was used in the assessment of system water quality under the current situation and after applying the proposed improvement interventions.
The study presented two improvement interventions. The first intervention proposed series of weirs across the system to enhance the air entrainment rate and re-aeration processes along the system. This improved the drainage water quality at Bahr Hadus new outfall to El Salam Canal as the concentrations of CBOD, TN and FC are reduced by 35%, 10% and 63% respectively while the DO concentration is increased by 35 %.
The second intervention considered controlling the pollution load of domestic wastewater point sources from surrounding catchments using treatment plants. This improved the drainage water quality at Bahr Hadus new outfall to El Salam Canal by reducing the concentration of CBOD, TN and FC by 31%, 18% and 60% respectively as well as increasing the DO concentration by 19%.
The two interventions simulation results indicated the necessity of further improvements to reduce the TSS and FC concentration to acceptable limits for reuse. Sediment basins upstream the main stream and tributaries and chlorination facilities at the pump station point sources were proposed to reduce TSS and FC concentrations by 83% and 95% respectively.
The cost investigated in the first and second interventions was estimated at 0.22 and 0.90 Egyptian Pound /m3 respectively.