الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
the rapid urban development of Alexandria city resulted in ,an increase in population density from 233 thousands in 1882 to ;1.4 5 mill ion sin 19 7 6 . It is projected that the permanent population of the city Iwi 11 increase from 2.45 million in 1976 to about 4.89 million in 11000. AWGA estimated that the actual 1976 average production was 1600,000 m3/day while the actual 2000 average demand 15 equal 11,530,000 rft~/cjay. On the other hand, supply ofThe efficiency of filters in the removal of bacteria depends on the type of the filter system and the type of backwash system. Both Italba and Patterson filters receive the same quality of clarified water. Sometimes, the bacterial counts of filtered water from Italba filter are higher than the bac terial counts of clarified water but the average percentage removal of bacteria by Italba filter There are fluctuations in the percentage removal of bacteri~ through filter run of the ordinary pilot filter. Sometimes the bacterial count of filtered water are higher than the bac- terial count of clarified water and with an average percentage reduction of bacteria from 13.9 to 15.3. In conclusion, to increase the efficiency of ordinary pilot filter, the depth of filter media must be increased with respect to its effective size, or decrease the effective size with respect to the allowable depth of filter media with the use of effective backwash system. .The efficiency of activated carbon bed in the removal of organic matter decrease gradually according the degree of ex haustion of activated carbon. Also there are fluctuation in activated carbon efficiency in the removal of organic matt~r. . The efficiency of activated carbon bed (with depth 15 cm) in the removal of organic matter ranged between 73 to 38.6 with average percentage removal of 51. While the efficiency of 5 cm depth of activated carbon bed in the removal of organic matter ranged between 59 to 6 with average percentage removal of 28.5. It can be concluded that the efficiency of activated carbon bed depends on the depth of that bed. - The activated carbon bed release bacteria causing great increase in the number of bacterial counts of filtered water because of bacterial growth on the Carbon. V. The sani tary survey revealed the followinq : - AWGA closed the intake at Mahmoudia Canal which proved to be polluted and now depends only on the intake of Drinking Water Ca na 1 . 403 1- The sides of Drinking Water Canal are not lined and may collapse, thus the capacity of the Canal may be reduced. J- The operation of Farkha raw water and the low lift pump stations depend on the alertness of the operator as there is no automatic control system. 1- The balance reservoir is considered to be in a bad sanitary condition and the capacity of the gravity line supplying the plant is limited. 5- The chemical preparation tanks for alum solution do not have facilities for mixing to produce a homogeneous solution. Equipments for the control of alum doses are not present and there are no good dispersion of alum solution.