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Abstract Land reclamation projects in the desert region are of vital importance for development of countries. Egypt governments do a great effort to increase the land reclamation. Heavy investments have been made to turn territories of the unproductive desert into green productive areas to survive the highly increasing rate of population. One of these areas is El-Salhia plain, which is located in the eastern fringe of the Nile Delta area between (Long. 310 50/ – 320 20/ E, Lat. 30 0 35/ – 300 50/ N). It is situated south west Port Said on the common borders of Port Said, El-Sharkia and Ismailia governorates. It is bounded by Ismailia Canal from the south, Bahr El-Bakar Drain from southwest to northeast and Suez Canal from the east. The groundwater from Quaternary aquifer beside the surface water from Ismailia Canal and its subsideries represents the main water resources for different purposes in this plain. The objective of the present work is to study the hydrochemical characteristics of water resources and to assess their suitability for different purposes. Field study and different analytical techniques (chemical and environmental) were carried out for the collected water samples (seven surfaceand thirty ground-water samples). Geomorphologically, El-Salhia plain is a part of the transitional zone between the Eastern Desert to the south and the Nile Delta to the north. It is fluviatile plain occupying the areas laying to the east of the cultivated lands of the Nile Delta and extends to the Suez Canal. It is represented by area lying to the north of Wadi El-Tumilate until the southern reaches of El Manzala Lake with altitude varying between 40m at the south to about 10m at the north. The northern and eastern parts of this plain are occupied by a considerable number of scattered, elongated and shallow sand dunes. The surface is occupied by sands 164 gravels, which are developed into a typical desert pavement. The coarse grain size characterizing the sediments of this plain reflects a good hydraulic characteristics, as well as a good environment for groundwater movement and accumulations. Geologically, The Quaternary deposits cover a vast area of the plain. These deposits are represented by loose quartizitic gravels, sands, superficial deposits, sand dunes, sabakhas, aeolian sands as well as fluviatile and fluviomarine deposits. Early Pleistocene deposits (old deltaic deposits) are dominating as coarse sand and flinty pebbles of igneous fragments. Tertiary rocks in the study area are recorded in the subsurface represented by Eocene, Oligocene, Miocene and Pliocene. Sedimentary succession in the study area is strongly affected by structural elements. Faults and folds are the most conspicuous structural elements affecting the landscape. Faults are dominantly represented by an NE-SW and NW-SE directions of normal type. Surface folds are detected out the area of study. In the subsurface, folds are detected by geophysical methods in previous studies in the Abu Hammad and Abu Sultan deep wells. The most important aquifer in El-Salhia plain is the Quaternary aquifer, which is mainly sand and gravel intercalated with clay and shales lenses. The aquifer thickness increases northwards. The southward thinning of the aquifer is due to E-W faults. It is a semi-confined fresh water aquifer, recharged from the Quaternary Nile Delta aquifer in the west and the seepage from Ismailia Canal. The depth to groundwater varies from 1m north El-Salhia to 20m near Ismailia Canal. The transmissivity increases in El-Salhia plain from the east to the west direction. 165 Concerning with water chemistry of the collected Quaternary groundwater samples of El-Salhia plain, the following characteristics are discussed: TDS ranged from 642 to 4530 mg/l with an average 1921mg/l. only one sample is fresh water (sample No. 3) and 41% belong to fairly fresh water referring to meteoric water influence. About 33% of the samples are slightly brackish, 20% consider brackish and only sample No.27 denote slightly saline water, reflecting leaching processes accompanying irrigation. Chloride-Sodium is the main water type, which represents about 74% of the groundwater samples. The main hypothetical salt assemblages comprise NaCl, Na2SO4, NaHCO3, Mg (HCO3)2 and Ca (HCO3)2; representing about 53% of samples. This assemblage is rich in bicarbonate salts which reflect the influence of fresh meteoric water. According to the rCl/ (rHCO3+rCO3) ratio, about 10% of the samples are located in normally fresh groundwater, 17% in slightly contaminated, 37 % moderately contaminated, 30% in injuriously contaminated and only samples No. 19&27 are plotted in highly contaminated groundwater class. The majority of the plotted groundwater samples (83%) occupy the diamond field subzones (7) of piper diagram (1944), which reflects primary salinity where Na+ and K+ exceeds SO4 2-. There is a positive correlation between Na+ and Cl- indicating that the majority of groundwater samples belong to Cl-Na type. Strong positive correlations are also between TDS, Na+, Cl- and SO4 2-. It is clear that there are also positive correlations between Ca2+, Mg2+ and total hardness, HCO3 - and total alkalinity. A negative correlation value is between DO and BOD, 166 as the increase of BOD lead to decrease of DO. Also, negative correlations between DO and NO3 -&PO4 3-, as the increase of NO3 -&PO4 3- lead to increase the growth of microorganisms which cause consumption of DO. Regarding to assessment of water resources for different purposes the following points are concluded: According to WQI, Ismailia and El-Kassara Canals S1&S2 and 70% of groundwater samples fall in good class which are recommended for drinking. Italy Company and El-Batikh Canals S4& S6 and 30% of the groundwater samples fall in poor class which must be treated before uses. El-Hosiniah Canal S3 belongs to very poor class and Abu-El-Dahab Canal and El-Qassassin drain S5, S7 are located in unsuitable class depending on different standards of drinking water quality. Most of the water samples are recommended for irrigation according to the acceptable limits for RSC, MH, NO3 -, PO4 3- and trace elements, while most of them are not recommended according to the acceptable limits for Na%, SAR, excess Cl- and TH. Regarding relative tolerance of crop plants to salinity, two samples (S1&S4) are suitable for sensitive crops, while three samples (S2, S3& S6) and 17% of the examined groundwater samples are suitable for irrigation of moderately sensitive crops. Abu-El-Dahab Canal and El-Qassassin Drain (S5&S7) and 66% of groundwater samples can be used to irrigate moderately salt tolerant crops. The remaining groundwater samples (17%) are only recommended to irrigate salt tolerant crops. So, the majority of analyzed water samples is unsuitable for irrigation under normal conditions and requires special management. All surface- and ground-water samples are unsuitable for paper and textile industry according to salinity except surface water samples (S1&S4), which are suitable for paper industry. For petroleum industry, all the analyzed water samples are in permissible limits of salinity except groundwater sample 27 which exceed limit 3500 mg/l. All the collected water samples are suitable for construction purposes according to the pH value and magnesium concentration except groundwater sample No. 10 which is slightly aggressive (magnesium concentration 100 - 300mg/l). Management of groundwater resources involves following up of hydrological studies by periodically continuous recording of water tables to maintain change in the storage of the groundwater and expected salt water intrusion. It also require stopping future drilling for groundwater wells in the western part of Ismailia area to avoid over exploitation of groundwater resources and replacing of groundwater by surface water to overcome the continual DROP of water table and intrusion of salt water from Suez Canal. The use of modern methods of irrigation for saving water as dropping and sprinkling and use of the brackish and saline water in irrigation of selected salt tolerance crops can save groundwater for future expansions. Construction of observation wells can be used for monitoring quality of groundwater due to seepage of water polluted to groundwater in future. |