الفهرس 
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Abstract
SUMMARY AND CONCLUSION
SUMMARY& CONCLUSIONS AND
RECOMMENDATIONS
The present study was erected in order to evaluate groundwater
resources in West Delta area and managing groundwater quantityfly and
qualityfly as well as to delineate the hydrological problems of reclaimed
projects, such as water logging, water depletion, and groundwater salinity
and groundwater pollution.
Topographically, the area is considered a low to flat land and the
ground elevation not exceeds 50 m above sea level. In the north the
ground surface is below sea level at abu EL Matamir and Hush Isa. The
geomorphologic units can be grouped according to their regional trends
into:
The young fluviatile plain, the old fluviatile plain, the structural plain and
the Mediterranean fore shore plain.
The sedimentary column from bottom to top starts by Oligocene
sediments. These sediments are of limited distribution in the study area
where Miocene, Pliocene, and Pleistocene Formations and Holocene
geologic units follow this up.
The well-developed section of Pleistocene deposits is 1000 m
thickness. Gabel El Basur is a young Pleistocene terrace covered by sands
and gravels. It is the floor plain of the Nile Delta during the earliest
Pleistocene. Hence during the Pleistocene-Holocene period, different
erosional processes produce different types of deposits. Alluvial deposits
derived from Miocene rocks, alluvial deposits derived from Pliocene
rocks, Sand dunes, and Deltaic deposits, and Marshes and Sabkhas, and
Lakes and water ponds.
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SUMMARY AND CONCLUSION
The resistivity field survey comprises measuring of the resistivity
values through 35 Vertical Electrical Sounding (YESes) covering almost
the whole area of study. The well known Schlumberger configuration
with electrode spacing from AB/2 = 1 to AB/2 = 200 m. in successive
steps is selected and applied in this work and the sounding curves of
measurements belong mainly to HK.,Q types.
The interpretation of these VESes was done usmg several
softwares for modeling seven geoelectric cross-sections were constructed
and they correlated with wells which located along it. Five of them take
east west direction and other two take north south direction.
The geoelectrical interpretation indicates that, the area can be
divided into four main geoelectric layers as follows:-
1- The first geoelectric layer
This layer is characterized by high resistivity values with respect to
other geoelectric layers where it ranges between 28 Ohm.m to 100
Ohm.m. Its thickness varies from 1 meter to 6 meters in the area where it
represents the surface layer, which composed of silt and dry sand
(heterogeneous layer).
2- The second geoelectric layer
It represents the clay cap layer which characterized by low
resistivity values ranged from 6 Ohm.m to 17 Ohm.m. The thickness
varies between 3 meters to 6 meters. It composed of clay or silt and varies
to sandy clay or silt in some localities in the area. This layer has a great
role in waterlogging problem in the area of study as it prevents water
infiltration from surface water drainage and leakage to the aquifer.
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SUMMARY AND CONCLUSION
3- The third geoelectric layer
This geoelectric layer represents the water saturated zone (aquifer).
It is characterized by middle resistivity values ranging from 11 Ohm.m to
39 Ohm.m.The thickness varies between 14 meters to 58 meters and
increases in the east and south-east in the area. It composed mainly of
sand and in some localities of clayey or silty sand where the main aquifer
in the area of study (unconsolidated water saturated aquifer). It consideres
the water-bearing zone in the study area where the most of drilled
production wells extract from this zone.
4- The fourth geoelectric layer
This layer is characterized by low resistivity values ranges from 3
to 8 Ohm.m. It represents the base of main aquifer in the area. It acts as
secondery target for drilling wells (it represents seconday aquifer). It
composes mostly of sandy clay or sandy silt with quality of water
mostly less than overlain zone (main aquifer).
Generally, the study area is characterized by the presence of two
water-bearing formations; as the follows:
1- primary aquifer
It is largely distributed in the area forming the main water bearing
formation of the study area, It is represented by the third geoelectric
layer.
2- secondary aquifer
It distributed in all the area too but it is great less of water quality
than the primary aquifer. It is represented by the fourth geoelectric layer
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SUMMARY AND CONCLUSION
Irrigation depends mainly on the surface water diverted from Nile
water through main canals and their secondary channels. The surface
water system includes EI Rayah EI Beheri, El Rayah EI Naseri, and EI
Nubariya canal, and EI Nasr canal. The groundwater aquifers can be
classified into: Nile Delta aquifer (Quaternary aquifer), which can be
divided into Recent aquifer and Pleistocene aquifer, Pliocene aquifer and
Miocene aquifer.
The Pleistocene aquifer is the main water bearing formation. It is a
highly productive aquifer. This aquifer is made up of successive layers of
sand and silty sand or clayey sand with occurrence of clay lenses of
fluviatile origin where the thickness of Pleistocene-Holocene deposits
ranges between 80 m near Cairo-Alexandria desert road and 300 m near
Kom Hamada and between 60 m to 80 m in the area of study. The depth
of water varies from a few meters close to the Delta to about 30 meters
near Wadi EI Natrun.
Twelve collected samples were analyzed in the area of study; they
represent the Nile Delta Aquifer. Salinity varies between 600 ppm in the
southern east and east and 3900 ppm in the south and of brackish type.
The hydrogen ion concentration (PH) of water ranges from 7.07 to 8.10. it
obvious that the groundwater is of alkaline type. Electrical conductivity
(EC) distribution in the area shows that the minimum value is 0.95 ms\cm
in sample of well W12 and the maximum (BC) is 5.98 ms\cm in sample
of well WlO as well as well W4.
The groundwater in the area is mainly ofNacl- type in the most of
the area however a board zone ofNa mix water is present due to maxing
of groundwater with infiltrated fresh water from the main irrigation
canals and excess irrigation water. In the east and south-east of the area
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SUMMARY AND CONCLUSION
the water type becomes NaS04 -type which refers to dissolution of
gypsum in addition to usage of fertilizers in some areas due to alkaline
nature of soil there.
Groundwater evaluation for domestic and irrigation use was
studied according to the hydrochmeical properties of water samples.
from these analysis we can deduce that:
I. The groundwater in the area is of brackish type. It not suitable for
drinking purpose where the TDS more than 1000 ppm.
2. The concentrations of Chloride, sulfate, Sodium and Potassium are
over the limit of standard groundwater for drinking purpose related
to European Economic Community (EEC 1975).
3. The concentrations of Magnesium, Nitrate and Calcium are in
allowable limit as related to European Economic Community (EEC
1975).
The suitability of water for irrigation has been classified into five
classes according to U.S. Salinity Laboratory Staff, 1954 diagram;
depend on the Sodium absorption ratio and EC in the samples of water,
which are
1. C3-Sl 2. C4-Sl 3. C4-S2 4. C4-S3 5. C4-S4
Most of samples are plotted in fifth class type which is
characterized by very high salinity and Sodium hazard.
Recommendations
1) The groundwater quality in Nubariya area was improved in
the last decade, this is due to installation of the drainage
system. Increasing the efficiencyof this system will assist in the
continuity of improving groundwater quality and overcoming
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SUMMARY AND CONCLUSION
waterlogging problems. Therefore, maintenance of the
drainage system is a vital goal.
2) The aquifer should be managed to make balance between
discharge and recharge to reduce the problem of increasing
salinity that have been observed in most wells.
3) The future development in the area should carry in east and
south-east of the area.
4) Decrease the usage of the agricultural fertilization to decrease
the salinity.
5) Reduce the extensive irrigation in reclaimed lands.
6) Using highly absorption salt crops to reduce salinity of the soil.
7) Usage of drainage pattern that penetrate impervious layer
(clay) in the waterlogging areas.
8) Periodical and continues recording for chemical analysis and
aquifer water level to observe any changes in future.