Environmental effects of different pollution sources upon the quality of the drainage water in drain number one, Dakahlia and Damietta governorates

The establishment of open drain network in the Nile Delta has begun in the second quarter of the last century. That network is in continued expansion to cope with increasing quantities of irrigation water particularly after the construction of Aswan High Dam, and the stress need to increase cropping intensity, in addition to horizontal expansion of the newly reclaimed lands. All open drains in Upper Egypt and some drains in South Nile Delta discharge into River Nile while the remaining main drains in the Nile Delta are either discharging into the Mediterranean Sea or into coastal lakes. Due to over population in the area, and increasing water demand, more Drain water is reused for irrigation. Drain No. [1] is a part of the open drain system in the Nile Delta. Drain No. [1] is situated to the north west of Damietta Branch of the Nile Delta extending from south to north for about 65 km through the Gov's of Gharbia, Dakahlia, and Damietta. The Drain stretch extending from Talkha City till the final pump station [48.700 km] is receiving the most pollutant discharges. The number of the most important tributary drains that discharge along Drain No. [1] are 23 tributary drains. The aim of this study is to evaluate the environmental effects of different pollution sources on water quality of Drain No. [1] in comparison with limits delineated by the Law 48/1982. The length of the studied Drain stretch is about 55.250 km. The part of the studied stretch that extends from Talkha City till the final pump station [about 48.700 km] was divided into 5 segments in addition to the final discharge portion [about 350 m]. During the study period, from Nov. 2000 to October 2001, twelve monthly sampling points were chosen along the studied Drain stretch. The sampling points were at the beginnings and ends of each segment, in addition to sampling point 1 located before segment 1 and sampling point 12 at the final discharge. Furthermore, four samples were collected during the year from the 23 tributary drains at discharging point to Drain No. [1]. Physical, chemical and biological analyses were carried out according to the Standard Methods for the Examination of Water and Wastewater

Water treatment plants assessment at Talkha power plant

Talkha power plant is the only power plant located in El-Mansoura. It generates electricity using two different methods by steam turbine and gas turbine. Both plants drew water from River Nile [208 m3/h]. The Nile raw water passes through different treatment processes to be suitable for drinking and operational uses. At Talkha power plant, there are two purification plants used for drinking water supply [100 m3/h] and for water demineralization supply [108 M3/h]. This study aimed at studying the efficiency of the water purification plants. For drinking water purification plant, the annual River Nile water characterized by slightly alkaline pH [7.4-8], high annual mean values of turbidity [10.06 NTU], standard plate count [SPC] [313.3 CFU/1 ml], total coliform [2717/100 ml], fecal coliform [0-2400/100 ml] and total algae [3 x 104 org/l]. The dominant group of algae all over the study period was green algae. The blue green algae was abundant in summer and autumn seasons. The pH range and the annual mean values of turbidity, TDS, total hardness, sulfates, chlorides, nitrates, nitrites, fluoride and residual chlorine for purified water were in compliance with Egyptian dinking water standards. All the SPC recorded values with an annual mean value of 10.13 CFU/1ml indicated that chlorine dose and contact time were not enough to kill the bacteria. However, they were in compliance with Egyptian degree [should not exceed 50 CFU/1ml]. Although the removal efficiency of the plant for total coliform and blue green algae was nigh [98.5% and 99.2, respectively], the limits of the obtained results with an annual mean values of 40/100ml and 15.6 org/l were not in compliance with the Egyptian degree [should be free from total coliform, fecal coliform and blue green algae]. For water demineralization treatment plant, the raw water was characterized by slightly alkaline pH. The annual mean values of conductivity, turbidity and TDS were 354.6 muS/cm, 10.84 NTU and 214.6 mg/l, respectively. There was an increase in the results of conductivity, turbidity, total hardness and TDS in carbon filter effluent which was attributed to the desorption of adsorbed ions on the carbon media. The removal efficiencies of turbidity, total hardness and TDS indicated the high efficiency of the cationic filter. The annual removal efficiencies of conductivity, turbidity, chloride and TDS proved the efficiency of the anionic filter for removing the dissolved and suspended ions. All of the recorded values of the pH, conductivity, turbidity, chlorides, hardness and TDS of the mixed bed effluent indicated that the water at this stage was of high quality for boiler feed. The study recommended adjustment of coagulant and residual chlorine doses as well as contact time and continuous monitoring and maintenance of the different units