الفهرس 
Chapter one: IntroductionOnly 14 pages are availabe for public view
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Abstract
135Assessment of physico-chemical and microbiological quality of raw and drinking water from sources to house hold was conducted. This study was carried out from November 2008 to November 2009 at Shebin El Kom drinking Water Treatment Plant.
A total of nineteen parameters were assessed in the physico-chemical
analysis of the water samples. Most water sources sampled were within
EPA physico-chemical standard for drinking water, but values of
phosphate, nitrite, iron and manganese exceeded the maximum permissible
limits (MPL).
Temperature ranged between 17.7 ºC in Winter and 28.3 ºC in Summer.
The results showed a noticeable seasonal trend of temperature.
pH of all water samples ranged between 6.5–8.5, which is considered
normal according to EPA.
The values of electrical conductivity did not exceed MPL (<2000
μmhos/cm), ranging between 346 and 381.98 μmhos/cm in raw water,
and between 336.33 and 425.40 μmhos/cm in tap water.
The TDS in the water samples were within the recommended limits, and
ranged between 195.53 and 247.99 mg/L in raw water, and between
196.43 and 294.72 mg/L in tap water.
The monthly concentrations of total hardness for drinking and raw water
fall within the allowed range.
Calcium and magnesium concentration were within the allowance range
(EPA) for drinking water.
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The raw water turbidity exceeded MPL. However, drinking water values
were within the safe limit of WHO for drinking water (Turbidity <5
NTU) except in Spring.
The chloride values in various stages of that water plant showed a
conspicuous variation. Thus, in Winter chlorides decreased from 39.67
in raw water to 30.5 in filtered water, but rose again to 36.0 in treated
water. This was even further noticed in tap water samples to 41.67. That
trend was also noticed during Summer and Autumn. Chlorides were
observed to be lower than MPL (<250 mg/L)
It is worth to mention that iron, nitrites, nitrates, Manganese and
phosphate values were markedly high in tap water. Those parameters
decreased in concentration in all seasons at different stages of treatment,
then rose abruptly in tap water, with a magnitude of 2 to multiple folds.
However, Manganese was represented by an exceptional high value in
raw, filtered and tap water during Spring and Autumn, while in treated
water high values were observed only in Autumn. Accordingly, potable
water in the studied area is dangerous to human health.
All raw water samples were positive for total coliform, fecal coliform,
E.coli, Salmonella and Shigella bacteria. The maximum values were
found in July (390 MPN/100ml), May (18 MPN/100ml), May (18 MPN/100ml),
September (153 CFU/ml) and August (340 CFU/ml), respectively. This may be
attributed to high pollution due to discharge of sewage into the water source.
For treated water, all samples from outlet of the water treatment plant
were free from total coliform, fecal coliform, E. coli, Salmonella and
Shigella bacteria. Moreover, samples from tap water were free from
fecal coliform, E. coli, Salmonella and Shigella bacteria, except for total
coliform. This indicated the presence of bio-film in distributed systems
tubes, so such potable water is considered unsafe for human
consumption.
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In this study different individuals of zooplankton (Protozoa and
rotifers) vary in their response to seasonal changes in the physical and
chemical nature of water.
Protozoa persisted all over the year, and 61 genera identified in raw
water samples, but were completely missing in filtered, treated and tap
water samples. This may be attributed to the effect of chlorination during
water treatment. The maximum population density of Protozoa during the
present study was observed during Autumn 1606 (Organism x10³/L) and
Spring 1424 (Organism x10³/L).
Monthly results showed a significant correlation between population
density of Protozoa and manganese concentration, while the obtained data
gave significant positive correlation between population density of Protozoa
against turbidity, ammonia and dissolved oxygen. Also, a negative
correlation between population density of Protozoa and total coliform
bacteria was found.
The total ciliate population showed clear seasonal variation, with the
highest counts in Autumn. Monthly results showed significant ciliate
correlations with physicochemical parameters.
Ciliated Protozoa showed significant correlation with ammonia, so that
ciliates are likely to play a positive role in maintaining and improving
water quality in aquatic environments with high-level of ammonium.
Ciliates showed that there is a positive correlation between population
density of ciliate and turbidity, Manganese and iron. Thus, ciliated
protozoa are suitable bio-indicators for heavy metal pollution in fresh
water environments.
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Ciliophora showed a daily significant correlation with total coliform
bacteria, suggesting that the predatory activities of ciliates upon the
dispersed growth of bacteria contribute to the reduction of coliform
bacteria
Rotifers can be used to indicate the performance of certain types of
water treatment process. The maximum population density of rotifers
during the period of study was observed in Summer (196 Organism
x10³/L) and Spring (187 Organism x10³/L).
The present results, showed a significant positive correlation between
population density of rotifers, turbidity and water temperature. While,
there is a negative correlation between population density of rotifers,
alkalinity and total hardness.
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Recommendations
As it is indicated in this study, water treatment in the examined water
plant, is more or less adequate but the efficiency of such treatment was
limited due to the malfunctioned distribution networks. Consequently,
the renovation of the distribution networks is a must, to succeed in
supplying safe potable water.
Monitoring the water treatment process and distributed water for safety
guarantee and checking up water samples for Arsenic, Lead, Mercury,
as well as pesticides residues.
Efficient techniques are required for the management of Water Plant to
ensure successful treatment of water.
Although this study was carried out on one water plant, it is thought that
the results are indicative for most Water Treatment Plants in Egypt.
The concerned parties or authorities should be formally informed by the
results and recommendations of this study, to carry out what is
necessary for safe drinking water supply. What ever the cost is, it will be
cheaper as compared to the health damage of the population, and the
subsequent expenditure by the government for treating the infected
people.