EFFECT OF THE WASTEWATER DISCHARGES ON THE WATER QUALITY OF BAHR EL BAQAR DRAIN

Abstract

The Egyptian water requirements in different fields are rapidly increasing while the water resources are limited. Therefore, the water planner started to consider the reuse concept including both agricultural drainage water and sewage water in irrigation. Bahr EL Baqar drain system in Eastern Nile Delta has been chosen to study the suitability of its water for reuse in irrigation. Field measurements and monitoring of the study area have been made to establish better understanding of the conditions of its surroundings and to identify the sources of pollution to the drain system. The monitoring program has been designed and executed to include five hydrological stations and eighteen sampling stations along the drain. The collected water samples have been analyzed to determine the physical, chemical and microbiological characteristics. The sediment samples, which have been collected from five locations along the drain system, have been analyzed to determine the distribution of the heavy metals in the drain system. The study shows that the microbiological health hazard is the major pollution problem to the drain system. The average value of coliforms bacteria for the drain water was 2.210° cell/lOOml. while, the concentrations of the heavy metals in water samples were usually under the limits which could cause problems to soils or plants except the cadmium. The sediment samples had high concentrations of selenium, vanadium, copper, manganese and cadmium. In case of reusing the drain water, heavy metals in sediment can be resuspended and increased in the reused water. The high salinity within the last reach of the system will cause severe problem to crops and soils. In addition, the high concentrations of .sodium and chloride may cause severe toxicity problem to crops