Introduction
It is well-known that Egypt lies in arid and semi-arid zone and that it depends mainly on its determined share from the Nile water for its water resources necessary for development purposes.
With this fixed water share and continuous increase in population, it is expected that the individual's share of water and arable land is decreasing unless this problem is dealt with through sustainable and continuous development of land and water resources and maximizing its uses and outputs.
It is also known that land and water are the basis of the process of food production as well as sustainable and stable development in areas of innovation, and intellect, hence progress and production.
Hence, the concept of food security and continual development in the developing countries had such importance and unique objective point specially in countries with limited water resources that lack the funds for importing food and other needs. Therefore, the persistent endeavor for achieving self-sufficiency which leads to limiting the imports to minimal levels that do not burden the state's budget is the basis that occupies the minds of planners and executors to fulfill the objectives of social and economic development.
The main axes for achieving these objectives were and will be represented in horizontal and vertical expansions in the field of agriculture and irrigation systems improvement, selection of strains, increasing the efficiency of different cultivation processes, and improvement of drainage as well as consistency of arable land because these are the factors leading to raising crop productivity. These axes also comprised the interest in providing new water resources, rationalizing and maximizing use of available resources, developing technologies for utilization of non-conventional water resources and interest in non-surface water resources including rainfall and surface as well as deep ground water.
Since the beginning of the last century, Egypt has tried to shift from basin irrigation systems to permanent irrigation systems. In the early thirties of this century, Egypt strived to expand agricultural areas and plant new lands, focusing on saline rainy lands in north Delta by draining parts of the northern lakes and some desert areas amounting to 95% from the area bordering the Valley and Delta in which total cultivated area in both old and new lands did not exceed 5% of Egypt's total area.
The Horizontal Expansion Project of Reclaiming and Planting some of the New Valley 's Lands in Egypt 's Western Desert is considered a dream for Egyptian generations particularly if this desert was a cell for producing and storing grains and food for the population in Egypt and other neighboring states during the rainy ages. The land of this valley is marked with low levels and high quality and that it embraces one of the available water sources requisite for irrigation represented in a ground stockpile. Though opinions differed in the source and sustainability of this stock, they agreed on its magnitude and accessibility in some sites. It is the reservoir of the deep Nubian sand stone in addition to other surface reservoirs.
It is noted that in the northern depressions starting from south in Al-Dakhla Oases, Abou Monkar, west of Al-Mauhoub, Al-Farafra, Al-Beheira and Siwa, water moves from the subterranean layers vertically upwards due to osmotic pressures that help spontaneous water flow without the need for lifting and pumping equipment till osmotic pressures lose effect and water sinks. At this point the necessary pumping devices are used.
Egypt started the experiment of land reclamation and plantation in the New Valley at large scales using the groundwater resources referred to at the end of the fifties and beginning of sixties in this century. That experiment was part of the state's ambitious plan to reclaim lands using groundwater and the water saved by the construction of the High Dam. Yet high ambitions did not meet the success that was hoped for. This was not because of a shortage in water, a defect in the land, nor the inefficiency of human resources, but is attributed in the first place to the lack of integrated and coordinated management necessary for mobilization, coordination and optimal use of their potentials.
With the issuance of laws and decisions under which the Ministry of Public Works and Water Resources will be responsible for managing all the water resources in Egypt whether these resources were Nilitic, non-Nilitc, conventional or non-conventional, and with the trends and objectives of the political leadership, the Ministry's officials started the tasks assigned to them. One of the most critical tasks was continuation of the old Egyptian dream of comprehensive development in the areas of the New Valley Oases.
This report discusses ideas and conceptions that were developed through studies, discussions and meetings held by the committees formed to examine the issue.
Water resources
Ground water is considered the only source for water in the New Valley . Ground water exists in the composition of the Nubian sand stone comprising two distinguished basins, i.e. Al-Kafra Basin that lies under parts of Libya , Chad and South Sudan and Al-Dakhla Basin which lies in the New Valley area in the Western Desert in Egypt .
Estimations differed concerning water potentialities of ground water basins in the New Valley . Yet most opinions agreed that age of this water ranges from 20 to 30 thousand years assuring that its renewability is limited and water stored in the different layers is fossilized water that had been leaked and stored since the rainy ages.
Most opinions also agree that the volume of the stock is enormous, perhaps exceeding 2000 milliard cubic meters; however this stock lies in three major zones. The upper zone depth reaches 200 meter, temperature of its stored water ranges from 25 to 30 Celsius. Depth of the middle zone reaches 400 meters and its temperature ranges from 30 to 40 Celsius. The lower zone is 650 m deep with a temperature ranging from 35 to 45 Celsius.
This classification may give an idea about the costs necessary for lifting water on one hand and the need to lower its temperature if it is to be used in irrigating arable land on the other hand. Therefore, the volume of the stock does not indicate the perfect economic suitability appropriate for use of water.
Statistics show that number of deep wells in 1961 in all the oases was 27 with a nearly total discharge of 150 thousand cubic meters/day. At that time, there existed about 1513 surface wells with nearly 450 thousand cubic meters/day of discharge. This situation changed completely by 1995 when number of deep wells increased to more than 550 wells whose daily discharge amounts to almost 2.4 million cubic meters. Increase in deep wells was because of decrease in water levels in many surface wells, consequently excluding them from operation so that its final number became 980 wells with total 250 thousand cubic meters of daily discharge in 1995.
Expansion Potentialities Using Groundwater
Indicators of sustainable expansion using ground water in the Nile Valley Area based on the lack of increasing the suction pipe than 100 meters in one hundred year point out the capacity of making the current abstraction to almost 2.5 milliard m 3 annually (nearly 6.8 million m 3 daily).
Land Sources in the New Valley Areas
The Current Situation
The cultivated area in the New Valley in the meantime is 65 thousand feddans to be cultivated during the winter. This area is reduced to become 35 thousand feddans during the summer. Agriculture uses more than 70 % of water pumped from wells or nearly 700 million m 3 annually (1.9 million m3/day).
Taking in account that agricultural lands' consumption of water in the summer is twice fold its consumption during the winter, water consumption rate of every feddan reaches 30 m 3 /feddan /day in winter. This rate rises to 60 m 3 /feddan /day in summer.
These numbers indicate also that water requirements for every feddan exceed 15 thousand m 3 /year while the findings of studies made on the region's water consumption and meteorology show that reference evapotranspiration does not exceed 8000 m 3 /year in Al-Kharga region and 9500 m 3 /year in Al-Dakhla. These findings explain extreme excessiveness in use of water in the mean time and the urgent need to rationalize this use in the future by developing irrigation systems and maximize water use.
Expansion Horizons in Agricultural Lands
It has been already pointed out that expansion can be carried out using ground water in the New Valley considering that the reservoirs potentials allow abstraction of 2.5 milliard cubic meters annually. 80% of this water will be used in irrigating agricultural lands which is equal to 2 milliard cubic meter/year and that the actual requirements of every feddan amounts nearly to 12 thousand m3/year after addition of crop treatment (10%) and washing requirements (10-15%) assuming that use of modern and improved irrigation systems will effectively amount to 80% thanks to the efficient field network of irrigation, distribution and transport. Thereby, horizontal expansion could be achieved by cultivating an area of 180 thousand feddans by use of ground water. This area can be distributed as follows: Al-Dakhla Oases (20 thousand feddans), Al-Farafra (30 thousand feddans) and east Al-Ewaynat (130 thousand feddans).
It is important to point out that climatic and topographic conditions involve planting trees that tolerate temperatures and aridity and can be loaded with cereal and fodders crops to utilize the shading provided by these trees which mitigates severe climatic conditions.
It is noteworthy that irrigation systems proposed for these regions are improved surface systems by substituting earth channels with lined and elevated channels manifest or buried pipelines and the use of modern irrigation systems particularly trickle irrigation system for trees, palm-trees and some vegetables types. The New Valley conditions should be taken into consideration for the application of exact scheduling systems of water drainage and allocating the crops the amount of water that they need in real time.
South Al-Kharga Area
Expansion potentialities in Al-Dakhla, Al-Farafra, and East Al-Ewaynat using available ground water were formerly discussed. Yet excavation works and the soil's classification imply the existence of large areas of lands south Al-Kharga Area which used to be called South Valley . It is expected that areas of first degree lands in this area would reach 50 thousand feddans and second degree lands would amount to 50 thousand feddans. There exists an area of 35 thousand feddans from third degree lands.
This depression's lands are marked with levelness. Its levels are mild for they are largely close to the Nile Valley levels at Aswan town according to some estimations (nearly 80-100 m above sea level). Yet these indications imply the improbability of ground water existence in large amounts enough for irrigating these lands. Hence it was thought to provide the area with surface nilitic water needed for irrigation.
Alternatives to Transporting the Nile
Water to the Region of South Valley
The process of transporting water through open courses and pipelines, working under the effect of gravity or operating with hydraulic pressure, controls the amount of discharge passing in every one of them, the slopes and the flowing water levels. In the case of upward slopes with open courses, water has to be lifted either at one or many stages to reach the required level.
As for Pipelines, water can be pushed by pressure equaling or exceeding difference in level at the beginning of the slope and its highest point in addition to resistance of the water flow in the pipe resultant from friction factors. By studying delivering Nile water to the area of South Valley in the New Valley Depression, two alternatives had to be taken in consideration. The first alternative involves abstraction from the Nile main stream downstream the High Dam during flowing near the town of Aswan and directing towards the north. While the second concerns abstraction upstream the High Dam at any suitable location on Nasser Lake heading south of the dam till the Sudanese Egyptian borders. Each alternative has its own distinctions as well as merits as much as faults and shortcomings. We shall review them in detail in the following parts.
Abstraction from the River Nile Main Stream
Downstream the High Dam
Studying the Nile Valley Topography which was basically formed from sedimentations of the Nile overflow for many years, one will find that the river is a deep stream bordered by the Valley's east and west banks. The valley's breadth differs a few meters at some sites till it reaches its maximal breadth near the town of Bani-Sweif where it reaches nearly 26 kilometers. The level of the Valley's banks differs according to the amount of water flowing into it in historic ages and sedimentations of water on the two banks in addition to the Valley's geological and morphological. The Valley's banks are bordered from the east and the west by a series of medium highlands. On the west side of the highlands in the area parallel to the River Nile within the area from Assuit in the north to Aswan in the south lie Al-Farafra Oases, Abou Menqar, West Al-Mauhoub, Al-Dakhla, Al-Kharga and the South Valley Oases whose ends extend to be opposite to Toshka Depression south of Aswan Town. Therefore, connecting any open or closed course from the River's main stream to the New Valley's Oases necessitates either rising to the summits of these highlands then sloping downwards with them to the level of natural land in the valley which approximates the level of the Nile Valley or permeating and penetrating these heights if they are broad enough to be drilled and penetrated. Till feasibility of the study is affirmed, four paths for open canal lines or pipes were chosen. We shall discuss each one separately:
1. Assiut /Al-Kharga Path
This path is the shortest one of the four for it is 210 kilometers long starting from the west of Manqebad Village which is far from Assiut Town (at level 50) and Al-Kharga Town (at level 75 meters above sea level). Between these two levels exists the west highland paralleling the valley to reach the level of 300 meters then declines again to connect to the New Valley . It is natural to lift water during its ascent on the highland through numerous pumping stations. After reaching the top of the highland, water starts to decline westwards, which requires establishment of many industrial works to diminish the power of water and weaken the force of its outflow. In its course, the canal intersects with many facilities which require constructing at least eight major bridges. It is also necessary to establish an electricity line of at least 120 kilometers length to feed the stations. The costs requisite for establishing these works inclusive of irrigation and drainage network required for the new lands (150 thousand feddans) were estimated to be 9 milliard L.E. It may be said that the foreign component will reach 50%.
2. Esna/ Al-Kharga Path
This path comes in the second place in terms of length after Assuit/Al-Kharga Path for there is no big difference between the two paths lengths. This path extends in parallel to the paved road linking Esna and Al-Kharga towns. The difference between the two paths is that the first path runs towards the western south while the second passes directly to the west, therefore it is obstructed by a series of highlands and western heights. Hence, the path begins with level of 75 upstream the New Esna Barrages, then reaches the summits of the highland where the level is 500 and continues on the same level then decreases to the level of 450, then 400 in an area exceeding 100 kilometer where it starts to decline to be 50 at Al-Kharga Town.
It is apparent from the two paths that penetrating the highland using tunnels is a difficult matter due to the long horizontal area and the nature of geological compositions. The preferred alternative is raising the canal or pipeline required for transferring water to the summits of the highland and returning back to the same level from which the canal or pipeline started.
It is normal that study of utilizing the declination in generating the power needed for lifting water is possible. It has to do with the amount of discharge and the extent of declination that would ensure producing economizing power.
Due to the great heights through which the Canal will pass, excavations will be double of those of the previous path, therefore estimated costs of this alternative will be very high reaching 36 milliard pounds.
3. Qena/Al-Kharga/Abou Tartour Path
Attention shifted to making use of that axes because of the passage of a Safaga/ Qena / AL-Kharga / Abou Tartour railroad in it. It was found also that this path that starts from level of 80 meters above sea level is headed in an upward slope to the highland till it reaches the level of 300 meters then it goes horizontally to an area of 50 kilometers and continue rising till the level of 480 meters above sea level. The overall shape of upward and downward slopes is similar to the shape of the slopes of Esna/ Al-Kharga line with the difference that the length of this line exceeds the double of length of the two previous lines , i.e. nearly 430 kilo meters, though excavations are much more less that those in the previous paths. So, total final costs may amount to 10.5 milliard pounds.
4. Aswan/Khafraa/Paris Path
This path follows Aswan / Abou Sembel Road , then heads west to link to Darb Al-Arbaeen Road which is historically known to be the land trade passage connecting Egypt with Sudan . As a result, delivering water to that area serves directly cattle, especially camels whose death rates were and will remain high because of lack of water. Despite the fact that this area is 400 kilometers long, the land topography is not as hard as the topography of the previous three paths. Consequently costs for establishment of the necessary works may be less that 9 milliard pounds.
Following the study of the former four paths, some preliminary results may be reached, for example:
I. Difference in levels of all the four paths necessitates considering the whole issue because passing a water course whether it is an open canal or pipeline in these arid lands and establishment of a large number of stations in such areas that lack the minimal services will make managing, operating and maintaining these stations a costly process. In addition, there are different possibilities of electrical and mechanical breakdowns during prime times that may lead under the prevailing climatic conditions of the lands, to which water will be delivered, to devastating the crops in a very short period of time - specially that the stations will be interdependent, in other words breakdown of Station 1 will lead to cessation of the last station in the series and consequently all the intermediate stations.
II. Economized water lifting, indicated by most references to be within 50-100 meters, has been enormously surpassed. Therefore, crop productivity will neither be competitive nor economical.
III. Costs of pipe lines are normally high compared to those of open channels because pipe lines require factors ensuring regular flow of water. Moreover, open channels in which water will run for an area amounting to hundreds of kilometers under high temperature and severe aridness in desert areas prove that evaporation rates from water surface of these channels will be extremely high. Passage of these channels in areas of creeping sands will make the blockage of water sector a frequent occurrence.
Operation of pumping and transforming stations and lines for transferring and distributing electricity as well as operation of the canal itself and the industrial works on it will require many skilled workers along the proposed path.
Therefore, it was thought that directing the path necessary for transferring water so that the canal would take water from upstream the High Dam ( Nasser Lake) instead of downstream the Dam.
Water Extraction from the Nile
Upstream the High Dam (from Lake Nasser )
It should be mentioned that water extraction upstream the High Dam had some determinants that may be usefully pointed out as follows:
1. Water abstraction from upstream the Dam should be within the agreement concluded between Egypt and Sudan regarding the Nile water distribution in accordance with 1959 Agreement.
2. The water level upstream the High Dam is fluctuating within the same year or many years, therefore establishing a fixed pumping station is almost impossible. Floating or diving stations conforming to fluctuation in the water levels will be necessary.
3. Any amount of water abstracted from upstream the Dam will affect even slightly the volume of electricity generation from the High Dam Electricity Station.
It is noteworthy that water extraction from upstream the Dam has many advantages, for instance:
1. The water level upstream the High Dam starts from 150 m above sea level in its minimal level and increases to be nearly 180m at its highest level, thus exceeding the water level downstream the High Dam with 70-100 m. As a matter of course, providing such compressing force will result in economization in lifting water to the same level of the compressing force.
2. The natural declination of the Nile Valley is directed from south to north, therefore it is expected that water lifting will be minimal as will be mentioned later.
Owing to the privilege of following the direction of abstraction from upstream the High Dam, the path chosen starts from Khor Toska and is headed westwards to connect to the road of Darb Al-Arbaeen where it ends at Paris town. The path is 350 kilometers long and starts at the lake's lowest level which is 150 and rises to the level of 250 through pumping stations till it reaches south of Paris Town where normal land level is 200 m above sea level. This path is the most cost-effective one for total estimated costs are nearly 7.5 milliard Pounds.
Conclusion
By studying the proposed paths that cover all the available alternatives for transporting the Nile River water to the area of south of New Valley , it seems clear that the most economically suitable one is the Khor Toshka/Paris path upstream the High Dam. Preliminary costs of this path are 7.5 milliard pounds, its length is 350 kilometers with maximal water pumping of 190m. It is noteworthy that the previous suggestion and costs estimations are a general and comprehensive conception that should be followed by pre-feasibility integrated studies and later by detailed feasibility studies.
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