الفهرس 
Chapter 1:IntroductionOnly 14 pages are availabe for public view
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Abstract
This study was carried out to show the performing efficiencies of four
water treatment plants; two surface water treatment plants and two ground water
treatment plants. These were Menof and Behwash as a former type, while
Shobra Blola and Meet Shahala as a latter type. This study was carried out
during a period extending from November 2008 to November 2009.
Samples were collected from some places at the different plants such as the
source, filter, ... etc. at Menof and Behwash surface plants, and from the outlet
of Shobra Blola and Meet Shahala as ground water treatment plants. Aquatic
samples were collected for twelve months between November 2008 and
November 2009. Certain physico-chemical parameters were measured regularly
during the studying period.
• Temperature ranged between 17 Cº during Winter and 26 Cº on Summer at
the different Water Treatment Plants .The results showed a noticeable
seasonal trend of temperature.
• The pH values of water samples ranged between 7.0 and 7.7 at the stages of
Menof and Behwash Water Treatment Plants, which is considered normal
according to EPA .
• The values of electrical conductivity did not exceed MPL(< 2000μmhos/cm);
varied between 338 and 469.6 μmhos/cm in Menof and Behwash, while it
was three folds higher in both ground water plants (Shobra Blola and Meet
Shahala) -
• Total Dissolved Solids (TDS) values in Menof and Behwash Plants did not
exceed 300.3 mg/L, while it exceed the MPL (500mg/L) in both ground
water treatment plants .
• Turbidity exceedes the Maximum Permissible Limits(MPL) (<5 NTU) in raw
water stages (sources) for both Menof and Behwash Plants, while those of
other stages were within the safe limit of WHO for drinking water which
were more or less similar to both ground water treatment plants .
• The seasonally concentrations of total hardness for drinking and raw water
did not exceed the Maximum Permissible Limits (MPL) except in Meet
Shahala water treatment plant during Winter season .
• Calcium and Magnesium concentrations were within the allowance range
(EPA) for drinking water except calcium values in ground water plants
(Meet Shahal and Shobra Blola) as it exceeded the limiting values.
• Chloride values at different stages of Menof and Behwash Water Treatment
Plants showed moderate variations. thus in Winter chlorides decreased
from 46 mg/L in raw water to 37 mg/L in filtered and rose again to 38 mg/L
treated water in Behwash, chlorides values were observed in both ground
water plants to be varied between 80 to160 mg/L, Chlorides were observed
to be lower than MPL(< 250mg/L).
• Manganese, iron and phosphate were markedly high in Ground Water
Treatment Plants, Manganese in raw stage of Behwash Water Treatment
Plant exceed the MPL (0.05) during Autumn, while it was within the right
range (EPA) in the other different stages of water plant in Menof and
Behwas -
• It was proved that bacterial samples of raw water at both Menof and
Behwash Water Treatment Plants were positive for total coliform , fecal
coliform and total coliform bacteria and their maximal values were obtained
during Summer. This could be attributed to the high level of pollution due to
discharging of sewage into the water source. Simultaneously, total coliform,
fecal and E.coli were detected in the source of the underground water which
could be referred to pollution by sewage as well.
All treated water samples at Menof and Behwash were found to be free of total ,
fecal and E. coli bacteria, while total coliform ,fecal coliform and E.coli were
present in tap water for both Shobra Blola and Meet Shahal. This might indicate
the presence of bio-film in the distribution system. Such water is considered as
unsafe for human consumption .
The maximal numerical values of Zooplankton were obtained during
Summer (6189 organisms x10³/L) and Autumn (4104 organisms x10 ³/L).
Protozoan organisms were detected all over the year where 71 genera were
identified in raw water samples for both Menof and Behwash plants. It showed
the uppermost densities among other planktons. It was completely absent from
filtered and treated water except in Behwash filtered water.
In this study the results showed a significant correlation between
population density of Protozoa ,Magnesium,Temperature, Turbidity and Total
coliform bacteria and a negative correlation between population densities of
Protozoa and total hardness.
Ciliated protozoa showed clear seasonal variations, with highest
numerical densities on summer at both Menof and Behwash Water Treatment
Plants. Seasonal results showed a significant correlation with temperature,
turbidity and total coliform bacteria. The maximum population density of-
rotifers was achieved during Summer (125 organims x10³/L) in Menof Plant and
80 organisms x10³/L in Behwash Water Treatment Plants.
The present study showed a positive correlation between rotifers and total
coliform bacteria and a negative correlation between rotifers and total hardness.