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<Integrated Waste Management Practices To Protect Freshwater Resources:
Case Studies From West Asia,
The Mediterranean, And The Arab Region>

    3.3 Characteristics of Non-Industrial Effluent

    a) Agricultural drains :
    There are two agricultural drain canals in the area. Information from the Drainage Research Institute is included in Table No. (3) below :

    Table 3 : Water Characteristics of agricultural drain canals

    Parameter
    El Tabbin Drain
    Khour Sail El Massara Drain
    Discharge 1000 m3/d
    159
      13
    TDS mg/1
      ton/d
    750
      49
    921
        6
    PO 3-
    4
    		mg/1
      ton/d
             0.44
             0.03
             1.16
                0.076
    NH3 mg/1
      ton/d
           0.1
               0.007
              0.02
                  0.0013
    NO3 mg/1
      Ton/d
    15
           0.99
       30
              1.97

    The following results represent samples taken from the drains:

    Table 4: Analyses of samples from the drains
    Parameters
    Unit
    Tabbin drain
    El Maasara drain
    PH  
      8.1
       7.76
    BOD5 Biological Oxygen Demand mg/1
    11.4
    12.6
    COD Chemical Oxygen Demand mg/1
    60    
    16    
    Oil & Grease mg/1
    Nil
    Nil
    TDS Total Dissolved Substance mg/1
    1739        
    313      
    TSS Total Soluble Substance mg/1
    29    
    26    
    CN-Cyanide mg/1
        0.02
    Nil
    PO 3- Phosphate
    4
    		mg/1
    7  
     1.5
    NO3 Nitrate mg/1
        0.02
    Nil
    Phenols mg/1
          0.065
    Nil
    Iron mg/1
    2  
     1.6
    Copper mg/1
      0.2
     0.4
    Zinc mg/1
      0.4
    Nil
    Chromium mg/1
          0.015
         0.024
    Cadmium mg/1
        0.02
       0.02

    The results from the samples indicate that the drain canals in the area are polluted by industrial effluents.

    3.4 Municipal Waste Water Treatment

    There is only one municipal wastewater treatment plant in the area, Tabbin waste water treatment plant. The design capacity is 350,000 m3/d with a peak flow of 420,000m3/d . Present average daily flow is 100,000m3/d. The plant consists of coarse and fine screens, sand trap, primary clarification followed by an activated sludge process. Separated oil and grease and primary sludge is de-watered and sent to the old plant. The excess sludge from the activated sludge process is sent to drying beds with impermeable clay layer at the bottom. The treated effluent is then chlorinated and used for irrigation. Table (5) below gives the analyses for march 1992:

    Table 5: Municipal Waste Water Treatment
    Parameter
    Unit
    Influent
    Effluent
    Min.
    Max.
    Min.
    Max.
    PH        7.09      7.65      7.28      7.93
    BOD5 mg/1 156      320      13    25   
    TSS mg/1 101      204      7 20   
    COD mg/1 196      320      19    40   
    N-NH3 mg/1 8 18       0.9    1.9
    N-NO3 mg/1 - - 5 10   
    Oil mg/1 26    42       0.9    1.5

    These are considered good results, and it is because low present load nitrification also takes place. The plant has the capacity to include treatment of industrial wastewater .

    3.5 Environmental Impact

    The only water source available in Egypt is the Nile River with some additional ground water. The need for drinking water and irrigation water for the country is mainly taken from the river. It is therefore essential to keep the quality of the river and ground water high. If the pollution is allowed to go on, the water may become unsuitable for irrigation, which would be a disaster for Egypt. From this study, it is clear that the Nile River at Helwan is suffering from the discharge of large volume of wastewater and pollution from different sources.

    Oil and grease were detected in all water and sediment samples taken in 1979 and 1992. High values of iron, manganese, Zinc, and to some extent, copper and chromium can be related to industrial wastewater discharges in the Helwan area.

    The situation does not seem to have improved since El-Gohary et al carried out a study (1975-1981) which indicated obvious deterioration in water quality in localized areas near the river banks at the sites of wastewater discharge, see Table (6). The extremely low dissolved oxygen concentration from the point of discharge and the next 80-100m out in the river is serious. Cooling water with increased temperature and low in oxygen, together with effluent high in biodegradable material, which during degradation consumes oxygen, may be the reason for this situation. At the study area, two factories discharge 10,000 kg BOD5/day. The degradation of this organic will produce in the order of 5,000 kg of biomass (bacteria, algae etc.) per day, consuming more than 10 tons of dissolved oxygen.

    Riverine fishery has been adversely affected. A reduction in the commercially desirable fish species has been recorded in places where river conditions deteriorated. Out of the 47 commercial Nile fish species recorded in 1947, only 17 species now exist, as recorded from recent surveys. This does not mean that the other species have completely disappeared, but they were not found in sufficient quantities to appear in the commercial catch.

    The ground water in the Tabbin area seems to be contaminated through the industrial activities in the area, possibly from the Iron and Steel factory and other industrial sources.

    The two drain canals in the area seem to be polluted through industrial effluent discharges. This is substantiated through the presence of trace metals and phenols found in the samples taken. The low content of BOD5, Ammonia and Nitrate indicates as should be expected, that aerobic and anoxic biodegradation of organic material takes place before the water is discharged to the river.

    Table 6: River Nile Water Quality at Cairo (After El Gohary , 1983)

    Constituent

    Concentration Range
    Temperature, °C 13 to 29
    Turbidity (Silica Scale), mg/1 10 to 100
    Total Suspended Solids ( 105°C), mg/1 5 to 60
    Total Dissolved Solids (150°C), mg/1 170 to 300
    PH 7.9 to 8.4
    Total Alkalinity (as CaCO3), mg/1 110 to 140
    Total Hardness (as CaCO3), mg/1 100 to 120
    Calcium, mg/1 18 to 28
    Magnesium, mg/1 9 to 15
    Chlorides (CI), mg/1 16 to 28
    Sulfates (SO4), mg/1 15 to 27
    Fluorides (F), mg/1 0.1 to 0.2
    Ammonia (N), mg/1 Not detected
    Nitrite (N), mg/1 Not detected
    Nitrate (N), mg/1 5 to 800
    Silicate (SiO2), mg/1 4 to 8
    Total Organic Nitrogen (N), mg/1 0.4 to 1.5
    Dissolved Oxygen, mg/1 7.2 to 9.2
    BOD (5-day, 20°C), mg/1 (Filtered samples) 1.5 to 3.0
    COD, mg/1 8 to 30
    Phenols, mg/1 2 to 300
    Chlorophyll a , mg/1 6.3 to 25.3
    Total Algal Count, cells/1 105 to 106

     

  1. Scope for Mitigation of Adverse Impacts

    Strategies for limiting the introduction of toxic and contaminating pollutants into the environment are of two general types, control and improvement of the main industrial processes, and control of effluent disposal.

    Experience accumulated during the last two decades suggest that in most cases it is more efficient and less expensive to incorporate pollution preventive measures than to install large "end of pipe" solutions. Therefore, more effort should be directed at redesigning processes to reduce waste of raw materials, to produce less byproducts and to assure systems that recycle, purify or otherwise fine use of by-products.

    According to the previous studies there is mounting evidence that pollution in a number of industries is a direct consequence of inefficient production practices, general water management and lack of enforcement of present regulations.

    The study area has a unique possibility to improve the situation relatively fast due to the new municipal wastewater treatment plant, which is in operation, and new sewer system, which is soon to be completed. The program for connecting the industry to this sewer system should be given top priority and speeded up.

    Industrial effluent, which is not harmful to the sewer system operation and to the process at the municipal treatment plant, should be connected to the sewer system without any delay. The Starch and Glucose Company is an example of such a factory.

    The metal processing industry will require some effluent pretreatment before they can be allowed to connect to the sewer system. Law enforcement and expert assistant will be required to improve this situation.

    The company discharging the largest water volume in the area is the Iron and Steel Company. To improve the situation here, an extensive study is first required both to improve the production and to save and recycle water. It is also necessary to reduce the amount of toxic pollutants as well as to reduce water infiltration to the ground. The result from such a study and implementations indicate whether this water should be connected to the new sewer system. Possibly should the factory have its own treatment plant and continue to discharge to the river. The hydraulic capacity of the municipal treatment plant may not be sufficient to handle this flow.

    4.1 Priorities for Mitigation of Adverse Impact

    If the following list of activities is followed, a considerable improvement will be achieved during a 3 to 5 year period.

  • Start enforcing existing industrial effluent discharge regulations.
  • Make expert assistance available to the industry.
  • Speed up the connection of industry to the new sewer system. Priority should be given to industry discharging to the river and drain canals, then to industry discharging to the desert.
  • Start a process and water study at the Iron and Steel Company, and have the results implemented as soon as possible.
  • Enforce the self-monitoring by the factories and follow up with external control of an appointed qualified organization.
  • Make the industry to teach their employees the necessity of pollution control and how each individual can contribute in his daily work. Without commitment from employees there will be no success. Experience from a number of countries.
  • Start a program, which makes it beneficial for the industry to reduce water consumption and water pollution.
  • Scope for re-circulating cooling water and slightly polluted waters.
  • Recycling of slightly contaminated waters in some of the more water intensive industry should be possible. Due to time limitation, this aspect was not followed up to any significant degree during the site visits. Some plants had a reasonable degree of re-circulation. Cooling water seemed not to be the major problem in the study area. Temperature pollution is small compared to pollution caused by organic and toxic contaminants.

    Ref. :
    Environmental Assessment & Screening of Helwan Area, World Bank Project, Cairo, June 1992

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