HYDROGEOLOGY AND HYDRO-GEOCHEMISTRY OF ......The Nile Delta area is approximately 22000 km2 and accounts for two thirds of Egypt’s agricultural surface, its smooth arcuate coastline,

Ninth International Water Technology Conference, IWTC9 2005, Sharm El-Sheikh, Egypt

395

HYDROGEOLOGY AND HYDRO-GEOCHEMISTRY OF THE

QUATERNARY AQUIFER IN THE MIDDLE NILE DELTA AREA, EGYPT

M. El Kashouty * and A. A. El Sabbagh **

* Geology Department, Faculty of Science, Cairo University, Cairo, Egypt

** Channel Maintenance Research Institute, Egypt ABSTRACT The study aimed to give an insight on the hydro-geological regime, and the hydro-geochemistry of the groundwater aquifer, detection the seawater intrusion limit, and applying irrigation with water of medium salinity. The study reveals that EC, Br, and Mg are contributed mainly by seawater intrusion, whereas F, I, and Ca are attributed to the anthropogenic sources mainly by agricultural impact. The measurement of the 18O and D contents help for identifying the probable source of the underground water. The historical review of the water-table altitude, total dissolved solids, and nitrate concentrations for the groundwater environment is established within a different periods. The latter parameters are depending upon the abstraction rate, seepage losses from irrigation canals, agricultural activities, and industrial effluents, and household wastewaters. The statistical analyses such as correlation coefficient, rotated factor analysis, and dendrogram technique, are used to differentiate the hydro-geo-chemical processes taken place in the aquifer-aquitard systems. The cluster method classified the groundwater into 4 groups, the first include groundwater have, EC ranges from 4.7 to 8.3 mS/cm, they are affected slightly by seawater intrusion through thick thickness of clay aquitard. Group 2 include groundwater have EC ranges from 3.3 to 4.2 mS/cm, influenced greatly by River Nile flushing. Both clusters are in the northeastern part of the study area. Group 3 include groundwater have EC ranges from 0.4 to 2.6 mS/cm, more affected by flushing Nile water than the previous group. Group 4 include groundwater, they are greatly affected by seawater intrusion through low thickness of clay aquitard than the first group, exists in the northwestern part. There is a good correlation between these clusters and the geographic position of the Mediterranean seawater and The branches of the River Nile situation. Using shallow saline groundwater to irrigate double cropping of wheat and summer corn enables increasing yields by 1.2-1.6 times, compared to yields of non-irrigated areas, in addition to it allows the regulation of four waters. The AquaChem program can help to mixing the River Nile and groundwater samples with a different proportions, to get the medium salinity (2.4 or 4 to 6 g/l.). The latter is used for irrigation alternating with fresh water (<1 g/l), so the hydrogeologic environment is improved. The historical review of water table altitude delineate a curvature appearance with time in the eastern Damietta Nile branch due to over-pumping. The NetPath program is used to detect the limit of the seawater intrusion from the first model, which is coincide with the results from Na, Cl, TDS, and Cl/HCO3 distribution. The second model is indicate the seawater intrusion

Ninth International Water Technology Conference, IWTC9 2005, Sharm El-Sheikh, Egypt 396

limit is extended in the south till Tanta. The results clarify that the seawater intrusion is enhanced by water table altitude, clay thickness of aquitard, pumping rate, and the water level in the River Nile situation. Keywords: Groundwater, Statistical application, AquaChem and NetPath programs INTRODUCTION The Nile Delta, once the largest depocenter in the Mediterranean, is now essentially a man altered coastal plain which has stopped building out into the Mediterranean and locally is receding. It is no longer an active natural delta [1]. The Nile Delta area is approximately 22000 km2 and accounts for two thirds of Egypt’s agricultural surface, its smooth arcuate coastline, 225 km in length, lies 160 km north of Cairo [2]. Land elevation decreases gently northward, from 18 m MSL near Cairo to less than 1.0 m near coast. The Nile water released by the High Aswan Dam to the delta,. A third of this amount is lost by evapotranspiration and infiltration to groundwater aquifers, and another two third moves slowly through the dense network of irrigation canal and drains [3]. The leaky aquifer is composed of two interconnected groundwater systems, upper one is clay aquitard and lower Pleistocene sand and gravel aquifer. Vertical flow between both is either upward or downward depending on the difference in hydraulic heads. The downward flow exists in the south while the upward flow exists in the north. The groundwater flow is directed northeast with average hydraulic gradient 13 cm/km [4]. The calculated transmissivity and storativity as average are 7500 m2/d and 6.1x10-4 respectively, [5]. Irrigation and drainage waters are infiltrated through clay aquitard to aquifer, affected mainly by clay transmissivity and aquifer storativity. Also the upward leakage is considered in the study area. The Nile Delta aquifer (Fig. 1) is recharged from agriculture wastewater, seawater, irrigation canals, and River Nile branches. The average rate of recharge is about 0.8 mm/day in Middle and southern part, while in the northern part, the infiltration irrigation water is intercepted by the drainage systems [6]. The intermixing between the invaded seawater and fresh Nile water is clear from the variation in chemical parameters within the different areas. It is difficult to estimate the interface and diffusion zone, but we try to identify these zones depending on the output of program and can compare with the determination using chemical ratios. MATERIALS AND METHODS The data used in the study are from the work of El Arabie et al (2001). The groundwater samples were collected during 1999. The data are analyzed by statistical and hydro geochemical programs such as AquaChem, China, and NetPath models.


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RESULTS AND DISCUSSION 1. Water Table Altitude Review of historical groundwater level data within 40 years can characterize the past and present hydrogeological conditions. A regional water table map of Pleistocene deposits was constructed from water table levels within different periods (Fig. 1). Groundwater flows from area of recharge (south) to areas of discharge (north, northwest, and northeast). Groundwater flow lines indicate not only the overall direction of flow but also where the flow is concentrating and the best selected favorable locations for new wells, which is in the eastern Damietta branch. Due to the increase of pumping rate, the situation of water level contour lines had been locally changed where its curvature gradually increased by time (Fig. 1) forming a semi closed zone, which indicates the presence of a cone of depression due to the over-pumping in the eastern Damietta branch. Water level change maps are used to calculate the changes in volume of water stored in an aquifer and as part of a water balance exercise. These maps are also useful when assessing the local effects of recharge and abstraction. This indicates that the cone of depression areas may be increased with time with abstraction and exploitation. Declines in heads in unconfined aquifer like such circumstances may be accompanied by intrusion of poor quality water (septic tank, seawater or cesspool) from the surrounding areas through high hydraulic interconnection. It is followed by a decrease in total pumpage and gradual recovery of heads, and limits the groundwater development in future long time. Elevated concentrations of organic carbon, small amounts of clays, and dissolved solids can enhance the movement of microorganisms [7] predicted from the farm practices. Groundwater flow in region A evolves to a low bicarbonate concentration through sub-regions B and C (Fig. 2). Recharge to the Pleistocene, aquifer which occurs by downward leakage through the unconfined part, is therefore responsible for high bicarbonate content in regions A and B than C. The exchange between Ca and Na ions is neglected in the hydrogeological environment (Fig. 2) because of the saltwater intrusion.


Fig. 1 Water table altitude within a different periods in the middle Delta.

Fig. 2 Concentration of HCO3, Na, and Ca with distance along flow path in Pleistocene aquifer Increasing of Na+ with Ca2+ trend clarify the neglected ion exchange

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2. Distribution of Selected Elements The concentrations of EC, Br, and Mg are increasing in the northwestern part of the study area (Fig. 3a, b, and c) indicate seawater intrusion with a rate higher than the northeastern part because of change in clay aquitard thickness, reaching about 25-40 m in the former direction while the latter area reaching about 60-70 m. Ca concentration is increasing in the northern part (at lake Burullus) (Fig. 3d) may indicate incoming from the drains, which are discharged to the lake. The shifting of increasing Ca concentration from northeast to north direction is attributed to mainly anthropogenic source (agricultural impact) and partially to seawater intrusion. Br in seawater is characterized by high concentration, it is increasing in the northwestern part (Fig. 3b), delineate Nile water flushing is decreasing in the last trend. The F concentration is increasing in the agricultural activity, near the intense drainage waste at Lake Burullus, and southern area (Fig. 3e). The mean of I content of seawater being estimated to be 58 �g/l, whereas the I concentration in drinking water range between 0.01 to 70 �g/l depending on the geographic position, topography, and rainfall pattern. The majority of groundwater samples have I content higher than the permissible limits suggest the anthropogenic input such as agricultural activity. I concentration is increasing in the northwestern and southern parts (Fig. 3f) , suggest a anthropogenic and lithogenic sources. Analyses of 18O and D can be used in conjunction with pair relationship to identify the probable source of underground water [8]. D is generally unaffected by reaction with aquifer materials at low temperature [9], whereas 18O also unaffected by reaction with silicates at low temperature for short period of times (< 1 million years or so) but exchange with CaCO3 in limestone aquifer, (may cause a significant shift toward heavier 18O values [10]. 18O and D are enriched in groundwater samples beside River Nile while from Tanta to Kafr El Shiekh, groundwater is clarify a depletion in isotopic contents. The isotopic concentrations are decreases in the northeastern and northwestern parts (Fig. 4a and b) due to decline in Nile freshwater flushing as predicted by the model (see Fig. 12). The isotopic contents of the Pleistocene aquifer is heterogeneous, ranges from –0.59 to +3.22 for 18O and from –0.3 to +23.7 for D. They suggest a mixing between different water types, formed from a different paleoclimatic conditions that dominated in Late Pleistocene period [11], and evaporation enrichment. Deuterium excess (d) is estimated by [12] as follow:

D = D % o – 8 18O % o.

All groundwater samples have d values < 10 %o, reflects the paleowater contributed by seawater, surface water bodies, and the surrounding aquifers. The d excess is figured (Fig. 4c) and clarify the high values are attributed to geographic position (near River Nile). Cl-18O relationship (Fig. 5a) shows the Cl concentration is mainly derived from seawater and partially from agriculture and geomedia. Cl and TDS (Fig. 5b) is clarify a different values for salinity that indicate different water types for instance sea water, Nile water, wastewater, and irrigation water from canals. The isotopic concentrations against the depth (Fig. 5c and d), indicate the general depletion with depth, may be from the low rate of Nile water flushing, especially in the northern part,


facilitated by the high thickness of clay aquitard. Few groundwater samples (in the northern) are deviated from the last trend, resulted from low evaporation process is associated with deep wells. Groundwater samples 148, 145, El Haddadi, and El Hamoul are decrease in salinity with time (Fig. 6). The River Nile is recharged much more these samples by time, may be resulted from more abstraction is applied, lead to decrease of water table than River Nile. Finally the River Nile is intruding the groundwater system and cause dilution by time.

Fig. 3 Areal distribution of selected ions in groundwater of Pleistocene aquifer

in the central Delta


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Fig. 4 Areal distribution of isotopic contents in groundwater of Pleistocene aquifer in the central Delta.

Fig. 5 isotopic contents versus Cl, salinity, and depth (meter).

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The historical review of total dissolved solids within 1985, 1991, and 1997 (Fig. 7a, b, and c) clarify an increase in salinity from 1985 to 1991’ period, resulted from the seawater intrusion, which is attributed to high abstraction rate. The total pumped water from the Pleistocene aquifer throughout the Nile Delta is about 5 * 108 m3/yr [13]. During 1991-1994’ periods, the total water pumped from only Damanhur, Shubrakhit, and Rashid govern orates, is about 4.8 * 106 m3/yr [14], and [15]. The increase in pumping rate from 1985 to 1991-1994, is clear when we compare these data keep in mind the total area. The 1997’ period (Fig. 7c) is indicate a decline in salinity, may be attributed to the decline in the abstraction rate in the Nile Delta, so the interface between freshwater and saltwater is moved back to the seaward. Also the recharge from the River Nile and a large number of irrigation canals constructed in the Nile Delta, can contributed a dilution. Also, the big irrigation projects for instance Nubariya and El Bustan can contribute to recharge the groundwater system The NO3 concentration is decline from 1985 to 2000 (Fig. 7d and e), may be from the decrease the amount and type of fertilizers or the recharge from a big irrigation projects or the flow of NO3 content or N ion after denitrification into the surface water bodies with groundwater flow. The oxic conditions are required for the persistence of NO3 in groundwater, where dissolved oxygen is limited, nitrate will not form and bacteria chemically reduce (denitrify) nitrate that is already present to nitrogen gas or to ammonia if sufficient organic matter is present [16]. The expected increase in organic matter and decrease in dissolved oxygen with time are attributed to the large number of wastewaters (mainly anoxic by for instance H2S) in the Nile Delta area especially during the last few years. The inflows of groundwater with low dissolved oxygen and rich in organic matter into the surface water that used as aquaculture are a serious for the aquatic species. 3. Statistical Application The correlation coefficient indicates that the depth is correlated with EC and Cl, reflect the highest salinity is concentrated in deeper aquifer than the shallow. EC is –ve correlated with F, indicate different sources for both, the first is contributed by seawater intrusion while the latter is attributed to agricultural activity. EC is correlated well with Br, clarify both parameters are derived from seawater intrusion. SO4 is correlated well with I, may be both are impacted by agricultural influences. F is –ve correlated with Br, delineate different sources, agricultural impact for the first and seawater intrusion for the latter. The factor analysis indicate 4 groups (Fig. 8), the first is positively loaded with depth, EC, Na, Mg, Ca, Cl, and Br indicate the seawater intrusion. Factor 2 is positively loaded with SO4, 18O, D, and I, reflect the evaporation process. Factor 3 is negatively loaded with depth and d excesses and positively loaded with F, suggest agricultural source for the latter. Factor 4 is negatively loaded with pH, and HCO3 indicate surface water leaching that agricultural activity is greatly affecting on the groundwater quality. Cluster analysis can identify 4 groups in dendrogram (Fig. 9) group 1 include samples in the northern part of the study area (due the Abu Madi area) except sample 16 is in the middle part. EC ranges from 4.7 to 8.3 mS/cm characterize them; they are affected slightly by seawater intrusion through thick thickness of clay aquitard. Group 2 include samples influenced


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greatly by River Nile, EC values are ranges from 3.3 to 4.2 mS/cm. Group 3 include samples more affected by River Nile than the previous group, ranges from 0.4 to 2.6 mS/cm. Group 4 include samples in the northwestern part (due Rashid village) , they are affected by intense seawater intrusion through low thickness of clay aquitard. . It is fair to ask if these clusters of samples have any physical significance meaning, or are just a statistical result. Plotting the subgroup value for each sample on a site map can tested the relationship of the statistically defined clusters of samples to geographic location.. The results shows that there is a good correspondence between spatial location and the statistical groups as determined by the HCA for instance Cluster 1 is located besides the highest thickness of clay aquitard.

Fig. 7 The total dissolved solids and nitrate concentration changes within different periods in the groundwater of the middle Delta area.


Fig. 8 Rotated factor analysis of isotopic and major ions contents

Fig. 9 Dendrogram analysis of the groundwater samples using major and isotopic parameters data transformed (Z score variable) modified by the program.


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Cluster 2 is located besides the lower clay thickness than the previous one. Despite both clusters are in the northern part but the salinity is changes because of the clay thickness changes. River Nile influences the rest clusters. It appears that the technique can provide valuable information to help define the hydrologic system. For instance, the high degree of spatial and statistical coherence in this data set could be used to support a model of hydrochemical evolution where the changes in water chemistry are a result of increasing rock-water interactions along hydrological flow paths, besides the aforementioned Anthropogenic degradation value for each sample on a site map can tested the relationship of the statistically defined clusters of samples to geographic location.. The results shows that there is a good correspondence between spatial location and the statistical groups as determined by the HCA for instance Cluster 1 is located besides the highest thickness of clay aquitard. Cluster 2 is located besides the lower clay thickness than the previous one. Despite both clusters are in the northern part but the salinity is changes because of the clay thickness changes. River Nile influences the rest clusters. It appears that the technique can provide valuable information to help define the hydrologic system. For instance, the high degree of spatial and statistical coherence in this data set could be used to support a model of hydrochemical evolution where the changes in water chemistry are a result of increasing rock-water interactions along hydrological flow paths, besides the aforementioned anthropogenic degradation. 4. China Model The percentage of wells of different qualities of shallow groundwater were, fresh water (<2g/l) 29%, slightly saline water (2-3 g/l) 25%, semi saline water (3-5 g/l) 12 %, and saline water (>5 g/l) 33%. Drought and fresh water shortages are the main limiting factors for sustainable development of agriculture in Nile Delta region. Using shallow saline groundwater to irrigate double cropping of wheat and summer corn enables increasing yields by 1.2-1.6 times, compared to yields of non-irrigated areas. It was applied in Nanpi Pilot area (China), [17], with water salinity of 2.4 g/l and 4 to 6 g/l. Exploitation and use of shallow groundwater enables regulation of the groundwater table at a sufficient depth to transform the variable natural rainfall into a more reliable water resource for the comprehensive control of drought, water-logging, salinity, and saline water. It not only increases crop yields but also allows the regulation of four waters [18], reducing the evaporation of phreatic water, increasing the rainfall infiltration, reducing the losses of runoff, and enhancing the function of water-logging prevention, soil salt leaching, and freshening of groundwater quality. The alternative use of saline and fresh water, according to the salt tolerance in different growth stages, allows optimizing the role and benefit of saline and fresh waters respectively. Saline water is used when irrigating salt-tolerant crops in the rotation or when irrigating salt-sensitive crops during a salt-tolerant growth stage. Fresh water is used at all other times. Whatever salt build-up occurs in the soil from irrigating with saline water, it is leached in a subsequent cropping period when fresh water is applied [19]. In the Nanpi area, fresh water (<1 g/l) was used during the seeding stage, and saline water (5 to 6 g/l) was used during the jointing stage, which


achieved a good harvest. The blending of saline water with fresh one decreases the salinity and sodicity because of the mutual dilution of the two types, and decreases the RSC by the chemical combination of the ions. Using saline water for irrigation differs from irrigation with fresh water, because it not only should meet the requirement of moisture of the crops, but also should control the damage by salt. The principles of salinity control for irrigation with saline water are that the salt accumulation in the soil should not exceed the crops salt tolerance limits, and that the salt added to the soil by irrigation with saline water should be leached by rain or irrigation water, so that the long term balance of soil salinity is maintained and that the salt accumulation does not occur in the root zone of the soil. The saline alkali land may reduce; the exploitation of shallow groundwater has thoroughly changed the conditions of water table. The present groundwater level was 15 m near Cairo decreases in the north to reach about 0.5 m, may decreases by used groundwater, create rainfall storage to replenish the hydrogeological environment. Accordingly, all the rainwater infiltrated into sub-ground, no runoff, water logging is out. It can help salt leaching, water quality improved, groundwater net may increase, the area with freshwater also may increases. The application of such model in the present circumstances of change of seawater intrusion rate, is required a special management and monitoring. The specific conductance of groundwater pumped from a monitoring well at a public supply well field should be measured twice each day by use of an automated groundwater sampling system called Robowell [9], and [20]. It can control and manage the seawater intrusion. 5. AquaChem Program The AquaChem program can estimate the combination between different groundwater samples and fresh water under the ground. AquaChem is a fully integrated software package developed specifically for graphical and numerical analysis and modeling of aqueous geochemical data sets. The mix samples tool mixes specific proportions of two samples from the open project database in a stepwise process. The net result is hydrogeological environment, regime, health, crops, income per capita, and fresh water area, and quality are all improved. Fig. 10 is the TDS decline by dilution estimated by AquaChem program and clarifies the saline and brackish water is decreased. Also the unsuitable output of TDS can repeat the dilution cycle to be used for irrigation purposes. Here, the TDS demand is around 4 g/l, to be used for irrigation alternated with fresh water in different stages like in China project. Fig. 11 delineates the selected mixing between groundwater samples to apply the resulted waters for irrigation instead staying underground. So the aquifer can recharge and diluted by surface runoff and the leakage water.


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Fig. 10 The output of AquaChem for the TDS concentration decline by mixing proportions steps of the River Nile and groundwater.

6. NetPath Program [21], [22], [8], and [23] and others discussed the chemical changes in water composition due to rock water interaction. In Netpath program, mixing of two or more initial waters is modeled to show hydrogeochemical processes taking place due to mixing and migration of waters from two or more sources of recharging groundwater aquifer. The prevailing minerals in the formations, through which the migrating water passes and interacts, were used in the model. The initial and final waters are River Nile and seawater. Ground-and surface-water chemistry cannot be dealt with separately where surface and subsurface flow systems interact. The movement of water between two solutions provides major pathways for chemical transfer between terrestrial and aquatic systems. This transfer of chemicals affects the supply of carbon, oxygen, nutrients such as nitrogen and phosphorous and other chemical constituents that enhance biogeochemical processes on both sides of the interface. This mixing zone establishes sharp changes in chemical concentrations, it enhance biogeochemical activity develops in shallow groundwater resulted from flow of O2-rich surface water into the subsurface environment, where bacteria and geochemically active sediments coatings are abundant. Actual chemical reactions depend on aquifer mineralogy, shape of the aquifer, types of organic matter in surface water, and groundwater, and nearby land use. The percentage of water from River Nile and seawater are estimated and figured (Fig. 12). Two models are determined from the output that established the limit of seawater intrusion. Assume the minimum percentage of seawater in groundwater samples is about 10 %, it is not only contributed by seawater intrusion but also from the anthropogenic sources, so above 10 %, the seawater impact is dominant. Model 1 is clarify the limit of seawater intrusion (Fig. 12a and b), which coincide with the limit depending on the distribution of the Cl, Na, TDS, and Cl/HCO3 (Fig. 13). On the other hand, model 2 (Fig. 12c and d) reflect the limit but more


extending in the south (at Tanta). The high abstraction rate in the eastern Nile Delta area may cause much decline in water table, favored the limit of seawater intrusion to be extended in the south as delineated by the second model. The decrease in thickness of clay aquitard in the south enhances the intrusion and increase the groundwater vulnerability. Anyway, we need to detect and monitor the problem occurrence and intrusion. In the middle and southern part of the study area, the groundwater samples should be automatically collected, analyzed for salinity, and send the data to net. It can carried out through five to ten monitor wells, to realize the seawater intrusion level, then it can drop the pumping rate to recognize the decline in salinity. At these conditions, we can use the groundwater safely in irrigation until the salinity increases by moving the diffusion zone toward the aquifer, then decrease the pumping and so on. Otherwise, the limit of seawater intrusion may be prolonged and attack a good groundwater quality to be useless. Table 1 and Fig.14 clarify the selected parameters as estimated by AquaChem program; the dissolved minerals are indicated also. In Piper graph (Fig.14) the water evolves to the sodium chloride facies.

1 2 3 4 5 6 7 8 9 1 0.1 0.17 0.23 0.30 0.37 0.43 0.5 0 0 0.9 0.83 0.77 0.70 0.63 0.57 0.5 1

Fig. 11 Mixing between low and high groundwater salinity with different proportions


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Fig. 12 Percentage of Mediterranean Sea and River Nile in the groundwater samples


Fig. 13 Areal distribution of selected ions to trace the limit of seawater intrusion. CONCLUSIONS AND RECOMMENDATIONS The natural occurrence and movement of saltwater has been enhanced by the development of groundwater resources for human uses. It lowered the water levels and caused saltwater to intrude into many of the region’ most productive aquifers. In response, substantial effort should be directed to understand the several pathways and processes that control saltwater movement through fresh water aquifer and the development of water quality observation well and networks and other monitoring approaches to detect and track saltwater movement. Seawater intrusion in the study area is resulted from a variety in hydrogeologic settings, sources of saline water, history of groundwater pumping, freshwater drainage. Also the recent rise in population is contributed to the problem. The main issues that should be described are periodic evaluation of the adequacy of groundwater monitoring networks and estimates of groundwater use; improved understanding of the controls on saltwater occurrence and intrusion; The role of groundwater in coastal ecosystems; and scientific evaluation to support groundwater management. One solution to deteriorating water quality is to increase recharge to the area, perhaps by infiltration of huge surface water, to reverse the incursion of saltwater.


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Table 1. The selected outputs of the AquaChem program

Sample ID Madi-17 Madi-5 Madi-1 Mesaed Madi-2 Arada-3 Water type Na-Cl Na-Cl Na-Mg-Cl Na-Mg-Ca-Cl Na-Cl Na-HCO3-Cl Total hardness mg/l CaCO3 679 626.8 627.5 2876.5 643.2 91

Ca/Mg mmol/l 1.234 1.234 0.261 0.693 0.818 1.213 Ca/SO4 mmol/l 0.366 0.366 0.397 1.97 0.621 1.065 Na/Cl mmol/l 1.159 1.159 0.947 0.491 0.966 2.395 Cl/Br mmol/l 680.89 680.89 222 208.82 257.29 186.933

Dissolved Halite (NaCl) mmol/l 185.0447 32.445 50.32 50.32 42.63 3.75 Dissolved Sylvite (KCl) mmol/l 0.7258 0.4374 0.75 0.746 0.4632 0.2316

Dissolved Anhydrite (CaSO4) mmol/l 10.236 3.706 5.965 5.97 4.664 0.468 D Dolomite (CaMg

(CO3)2) mmol/l 5.811 5.811 0.031 Carbonate (CaCo3)

SampleID Mkassab MedSea Mhabasha-244 Qulienkadr Water type Na-Mg-Ca-Cl-HCO3 Na-Cl Na-Ca-SO4-Cl Ca-Na-Mg-Cl-HCO3 Total hardness mg/l CaCO3 1108.1 7481.5 781.7 351.2 Ca/Mg mmol/l 0.897 0.191 1.5 1.668 Ca/SO4 mmol/l 1.511 0.436 0.335 3.148 Na/Cl mmol/l 0.835 0.857 2.583 0.522 Cl/Br mmol/l 228.74 573.98 1538.9 206.9

Dissolved Halite (NaCl) mmol/l 16 566.46 12.1 3.78 Dissolved Sylvite (KCl) mmol/l 0.59 10.57 0.23 0.205

Dissolved Anhydrite (CaSO4) mmol/l 3.467 27.6 13.992 0.698 Dolomite (CaMg

(CO3)2) mmol/l 1.77 1.316 Carbonate (CaCo3) 0.1819

Madi-4 Arada-2 Arada-4 Arada-5 Elhadady Elhamoul Elwastani Tanta-333 Haikal-190 Na-Cl Na-Cl Na-Cl-HCO3 Na-Cl-HCO3 Na-Mg-Cl Na-Mg-Cl Na-Cl Na-Ca-HCO3-Cl Na-Cl-SO4 1786.5 80.8 1.516 0.633 2469 2923.1 958.6 94.5 524 0.956 1.617 1.198 0.27 0.876 0.804 0.714 2.831 0.4 1.808 3.994 1.349 1.113 2.914 3.31 2.217 16.776 0.166 0.706 1.09 228.83 211.118 0.679 0.611 0.808 1.415 1.14

229.124 157.328 18.19 32.822 236.3 276.28 296.3 112.69 244.5 60.89 19.62 0.515 1 79.16 74.33 53.023 2.116 25.51

0.4889 0.669 0.625 2.217 1.287 5.352 1.85 0.283 2.34 4.831 0.125 0.124 3.958 3.935 1.8 0.042 8.995 3.902 0.309 7.57 9.089 2.19 0.247

0.065 0.4106 Rasheed Rnile Ssalem Selahad-36 Soapman Tmounfia-24 Tanta-20

Na-Mg-Cl Ca-Mg-Na-HCO3 Na-Mg-Ca-Cl Ca-Mg-Na-HCO3-Cl Na-Cl Na-HCO3-Cl Na-Mg-Ca-Cl 8246.1 200.1 2870.7 189.7 1696 133.9 955.1 0.176 1.221 0.955 1.713 0.623 0.809 0.888 0.5 2.05 1.85 28.759 1.39 38.35 2.876

0.819 1.42 0.674 1.175 0.76 1.1 0.625 369.99 142.74 842.73 175.3 251.57 188.8 83.33

531.231 0.7113 81.73 0.8101 70.2 3.78 24.1 6.22 0.201 1.2 0.386 1.72 0.59 0.87

24.663 0.435 7.57 0.042 4.7 0.016 1.56 0.565 6.44 0.699 1.8 0.583 2.93 0.4571


Fig 14. Graphical representation of groundwater samples of the middle Delta


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human impact. Science, 260: 628-634 pp. [2] Stanley, D. (1996): Nile Delta: extreme case of sediment entrapment on a delta

plain and consequent coastal land loss. Marine Geology, 189-195pp. [3] Sestini, G. (1992): Implications of climatic changes for the Nile delta In: L. Jeftic,

J.D. Milliman and G. Sestini (Editors), Climatic Change and the Mediterranean. Edward Arnold, NY, 535-601pp.

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HYDROGEOLOGY AND HYDRO-GEOCHEMISTRY OF ......The Nile Delta area is approximately 22000 km2 and accounts for two thirds of Egypt’s agricultural surface, its smooth arcuate coastline,