The main source of fresh water in Egypt is the Nile River with a limited discharge of 55.5 billion cubic meter/year and most of this source�s water is already allocated. In addition to the Nile river, there is a big potential of deep groundwater in Egypt, specially in the Western Desert Oases and East Owaynat area, and only a small portion of this groundwater is used. Because of the limitation of fresh water in Egypt and the expected increase of population in the next decades, an increase in future water demand is expected. A series of national level projects are designed to conserve water such as the irrigation improvement projects, the reuse of drainage water, the rehabilitation of existing irrigation structures, and several projects to reduce water consumed on the farm level. Conserved water may be used in new land reclamation and development projects such as Southern Egypt development project. Southern Egypt development project have an integrated scheme which include, in addition to land reclamation other activities such as agriculture products industry, mining industry, and tourism. This would require the construction of canals, drains, roads, electrical network, new cities and villages, and domestic and sewage networks.

The horizontal land expansion consists of two parts. The first part is the area that will be cultivated on Sheikh Zayed Canal with a total of 540,000 feddan. The canal would get its water supply from Lake Naser through a huge pumping station with a total discharge of five billion cubic meter/year. The second part is concerned with the development of the Western Desert Oases and East Owaynat on deep Groundwater, and about 500,000 feddan will be cultivated on Groundwater in the first phase of the project.

The objective of this paper is to present and analyze the important role of GIS in Southern Egypt development project starting from the planning stage. The topography of the area and the hydraulic characteristics of the lake would determine the canal intake pump station location. The topography and soil classification would determine the path of Sheikh Zayed Canal and its four branches, the areas to be cultivated, and new roads. In addition to soil classification, the climatic conditions of the area such as temperature, relative humidity, rainfall, evapotranspration rate, and wind velocity would determine the suitable crops for the area and the water requirements for each location. Other geographic layers employed in Southern Egypt development project include the layers of existing cultivated areas in the Oases and its water requirements and population and existing roads.

The GIS is one of the tools used to control and organize the flood of information needed to assist the decision makers in there planning and water management of Southern Egypt development project.

Egyptian interest in desert development has increased in the twenty century. Many of the previous development projects did attract too much attention and investments but it did not accomplish their objectives because little efforts were directed toward integrating these projects from the beginning into a global strategic plan. Some of these previous projects include (Mouselhy, 1996):

1. Suiz Canal area development project
2. The New Valley development project
3. New Cities project
4. Lake Nasser planning and development
5. Development of the North -West Coast and North Sinai.

The purpose of this project is to construct new communities with huge capability that can be self-sufficient and absorb part of the population from the Delta and the Valley to reduce its population intensity. Many of these projects lack the global strategic planning which led to failing short of attracting permanent residents and investment opportunities with the exception of Suiz Canal area development project that attract more than two million resident over a century.

To summarize, the strategic planning for desert development projects have to satisfy the following requirements (Mouselhy, 1996):

1. Reliable source of fresh water and food self sufficient.
2. Efficient systems for transportation and communication.
3. Economically integrated sectors with respect to place and activities such as agriculture, industry, mining, tourist, and energy.
4. Giving more attention to new industries based on local materials and manufactured specially for exporting.

The GIS tools can organize and store old and new water related data into a database and make a spatial link between the information in the database and its related location on the map. The GIS tools used in this paper are the ArcInfo software and the Arc/view software. It is used to store, analyze, and display spatial referenced data. The technique will be employed to overlay several layers of Sheikh Zayed canal project to study and investigate the different elements of the project and enables the decision makers to make a well informed decision regarding the planning and management of the project components.

According to the expansion sector plans, a total sum of 3.4 million feddans will be reclaimed from the year 1997 to the year 2017 and this area is distributed as shown in table (1) (Expansion Sector, 1997). These areas are designed to be irrigated using either drip or sprinkler irrigation methods.

The Ministry of Public Works and Water Resources is conducting national scale projects to conserve water that would be used for the future reclamation through the year 2017.

A list of the sources for conserved and augmented water is shown in Table 2. (MPWWR, 1997).

Egypt has a limited share of the Nile River water estimated at 55.5 billion cubic meters. Because of the limitation of this river source, Egypt has to manage and utilize it in every possible form of development, so it can satisfy all the present and future requirements including agricultural, industrial, tourist, river transport, drinking, and power generation activities. Expanding the circle of development in Egypt in any direction is based on the availability of fresh water. Accordingly, Sheikh Zayed canal project is part of southern Egypt development project where it carries the water from Lake Nasser and heading toward the western desert. The project is a huge step toward reducing many of the social problems such as poverty, unemployment, backwardness, terrorism, and reducing population densities and degree of pollution in the old valley.

Southern Egypt is considered a very dry tropical arid region with less than 1 mm/year average rainfall. The average temperature ranges from � c in January to 32 � c in July. The absolute temperature ranges from the minimum of 1.3 � c to the maximum of 50.3 � c. The wind velocity ranges from 3 km/hr to 5 km/hr with a relative humidity ranges from 19% in the summer to 45% in the winter.

4.2 Agricultural water requirements

For the agriculture water requirements, it is estimated that the average evapotranspration for the project area is 4.97 mm/day which add up to 1816.6 mm/year. By adding consumptive use which ranges from 7000 - 9000 m³/fed/year, including the leaching and losses requirements, the total water requirements would amount to about 9000-11,000 m³/fed/year.

Sheikh Zayed Canal is part of the Southern Egypt development project where it would carry the Nile water to the fertile arable lands in the depressions and oases of the western deserts. This canal would ensure flow of water all year long, no matter what is the water level in Lake Nasser.

Reclamation of the Egyptian deserts started in the 50�s by The General Authority for Desert Reclamation, where they implemented pilot reclamation projects and started research in the fields of geology, hydrology, geophysics, topographical survey, and soil classification. Related studies continued in 1963 investigated the use of Lake Nasser to cultivate the valley and recharge the groundwater in the oases. In 1969, soil classification study were completed and proposals were presented for digging a canal from Toshka depression to the New Valley for reclaiming new lands from south of the Valley to El-Kharga oasis. In 1980, a proposal was presented of a new valley start from Toshka, passing through the desert oases of El-kharga, El-Dakhla, El-Farafra, El-Bahryia, and ending at El-Kattara depression.

The Agriculture Research Institute and the Desert Research Center carried out several studies that prepared soil classification maps of the area lands which shows the existence of large areas suitable for reclamation. An important encyclopedia about the western desert was prepared by the Academy of Scientific Research in 1989 that contains in four volumes all the available studies regarding water resources, soil, plants, animals, minerals, and touristic resources in the area since ancient times until now. In addition to that, the National Water Research Center represented by its twelve research institutes, carried out several field studies to asses the potential groundwater in the area, survey present wells, and pinpointing agricultural drainage problems in the New Valley Governorate.

Many studies of land suitability for cultivation in the western desert have been performed in the past. The lands were classified based on the Food and Agriculture Organization (FAO) specifications and the degree of suitability for reclamation was based on:

1. The degree of land leveling and slope.
2. The texture, depth, percentage of the surface and subsurface of the soil.
3. The percentage, condensity, and depth of the pebbles, rock, and sand.
4. The soil permeability and its ability to retain water which determine the irrigation water requirements.
5. The percentage and distribution of calcium carbonate, gypsum, and dissolved salts.

According to these factors, the land suitable for cultivation was classified as shown in Figure (1) with the following:

1. Highly suitable for cultivation (very good)

One of the best land which has almost leveled surface, deep soil, and medium texture with little pebble and stone constituents. Its area amounts to 501,633 feddans.

2. Suitable for cultivation (Good)

It is well suited for cultivation with leveled surface, deep soil of clayey to sandy loamy texture with no pebbles. Its area amounts to 383,144 feddans.

3. Medium suitability for cultivation (Medium)

It has medium suitability with most of its area leveled except for small areas. Its area amounts to 1,249,405 feddans.

The remaining area either not suitable for cultivation because its land has gypsum formations or hard rock, or sandy soil with limited suitability for a limited kind of crops. Other areas are not suitable for agriculture because of its high soil salinity content that needs soil leaching with a good drainage network.

The economic feasibility study conducted contains many elements, and the cropping pattern for the area is one of the most important items. The cropping pattern distribution detailed study was conducted by the Agricultural Center Institutes to give the highest net revenue from the investment unit, land types, and water. Experimental station in the area will be established to study the possibility of cultivating several crops. The researchers will focus on the crops that can resist drought, high salinity, high and low temperature changes, and self - resistance to agricultural pests. This work would be integrated with the hydrological data of the meteorological network that will be established by the National Water Research Center Institutes, to help evaluate the water needs. Experts suggested some crops that fits the tropical region such as equatorial fruits, medicinal and aroma herbs, and some kinds of citrus plants and olive that endures drought and salinity. In addition to that, the experts confirmed the possibility of growing many other crops such as vegetables and wheat.

Four previous routes were studied to withdraw water from downstream the dam as shown in Figure (2) and each has its advantages and disadvantages as follows:

1. Assiut/ El-Kharga Route

This route crosses the western plateau with a length of 210 kilometers and require a high pumping cost and many control structures.

2. Esna/ El-Kharga Route

This route is a little longer than the first one and requires a high pumping cost to cross a series of plateaus and hills.

3. Qena / El-Kharga/Abu- Tartour Route

This route runs parallel to the Safaga /Abu-Tartour railways with double the length of the two previous routes and exceed their estimated cost.

4. Aswan/Khafraa/Paris Route

This route runs 400 kilometers following aswan/abu simbel road then heads westwards to merge with Darb El-Arbeen road that made it along and costly route.

The Study of the previous four routes indicated that:

• The cost of lifting through out the routes is uneconomical.
• The estimated cost of replacing open channels with tunnels or pipelines was proven to be more expensive.
• The cost of operation and living expenses for the skilled labor that runs the pumping stations and diversion structures proven to be very expensive on the long run.

This route, as shown in figure (2), pump water from Lake Nasser, 8 km North of Toshka spillway, through a huge pumping station and head westward for 70 kilometers where four branches will be diverted from its main canal. This route proven to be the best alternative because of the natural land slope from the beginning of the main canal and its end. A lot of energy is saved by lifting water from the lake and energy cost gets lower, as water level in the lake gets higher, this route is estimated to have the lowest quantities of soil excavation compared to the other four routes.

Due to the given reasons this fifth route were chosen for the project.

This pump station is located on the left bank of lake Nasser about 8 km north of Toshka spillway as shown in figure (3). The pump station is designed to lift water from Lake Nasser to Sheikh Zayed main canal with maximum static lift of 52.5 meters to cover the difference between the lowest level of Lake Storage at elevation 147.5 meters, and main canal water level at elevation 200 meters. The withdrawal from the lake will be through tunnels and discharge through pipelines with a total designed discharge of 25 milliom³/day that could be raised to a maximum of 37 million m³/dayusing 24 pumps. The energy needed to operate the pumping station varies according to the lake water level from 200 M.W. to 375 M.W.

The main canal starts from the main pump station and heads westwards about 70 km. The main canal is designed with a bed of 30 meters width and 6 meters water depth, in addition to one-meter free board, with a side slope of two to one. The cross section of the canal is lined to prevent water leakage and the maximum canal capacity is 30 million m³/day. Two different routes for the branch canals were proposed, In the first alternative, four branch canals are diverted from the main canal with a total length of about 167 km and to serve a total area of 540 thousand feddans in the first stage. The four branches locations, lengths, command area maximum discharge and other criterias are shown in figure (3) where:

Branch (1) serve 140,000 feddans with a length of 57 km.

Branch (2) serve 145,000 feddans with a length 60 km

Branch (3) serve 100,000 feddans with a length of 28 km.

Branch (4) serve 155,000 feddans with a length of 22 km.

By using the GIS technique, it was possible to overlay the three geographic layers of soil classification, branch canals routes, and the boundary of each canal command area. As shown in Figure (3) it is concluded that:

• For branch canals (1) and (2), the branch canal courses are passing to the side of the canal command area boundary.
• For branch canal (4), the branch canal is not long enough to cover a bigger portion of the canal command area boundary. In addition, the north part of the boundary have no canal to supply it.
• Branch canals (1), (2), and (3) are passing mainly through medium suitability for cultivation land, even through there are areas with good and very good suitability for cultivation areas in the Northwest part of the area.

The second alternative route as shown in figure (4) consists of three overlaid geographic layers which are the branch canals, soil classification of the area, and the boundary of each branch canal command area. This route have several advantages over the first proposal, such as:

• Branch canals (1), and (2) pass through the chosen boundary of each canal command area which give better distribution of water through head regulators to the right and the left of the branch canal.
• Branch (4) is long enough to reach a bigger portion of its canal command area.

The main and branch canals will contain many hydraulic structures and the initial design of pump stations, Head regulators, intermediate regulators, and bridges are shown in figure (5).

Several field studies were accomplished in the project area by the different ministries and research institutes to determine the different characteristics of the project component, such as:

1. The geo-technical study aims at preparing geological maps of the area, studying the cracks, earthquake movement, movement of the sand dunes, and the characteristics of the sedimentation cover and base rocks.
2. Detailed survey studies helped in determining the canal course and the service road. In addition, maps with different scales were prepared to help in the on going construction work.
3. Soil mechanics studies were performed along the canal and the pumping station location to carry out soil tests, material specification tests, and chemical analysis. A complete laboratory and a huge excavator were employed in and near the site for soil testing.
4. Hydrographic and hydraulic studies were carried out for the intake feeding the pumping station starting from Kalabsha to Toshka area west of Lake Nasser. The studies used physical and mathematical models to simulate the directions of the water currents, the movement of material in the lake bed, erosion and sedimentation phenomena upstream the intake, and water hammer phenomena.
5. varies studies were conducted to limit drainage water and its negative impact on the environment. The proposed solutions include the use of drainage water in growing high tolerable crops and timber trees, creation of artificial lakes for touristic and recreational activities, and extracting solid salts for industrial activities.

The development of the western desert oases and East Owaynat is part of the southern Egypt development project. The main source of groundwater in the western desert is the Nubian sand stone aquifer that prove to have good fresh water suitable for all kinds of activities. The studies showed that the Nubian aquifer has a huge storage capacity and its water is non-renewable except for a very small amount of about 8 million m³ annually. The main oases in the western desert include El-kharga, El- Dakhla, El-Farafra,

El Bahariya, and Siwa. In addition to the oases, there is a big potential of groundwater and good land in East El-Owaynat and Darb El-arbeen area, where the location of these areas and the different oases is shown in figure (6).

Even though the western desert occupy two third of the Egyptian land, its population were estimated in 1995 at 551,000 resident (Sabri Hamad,1996). Many of the oases have cultivated areas in addition to the areas reclaimed from 1960�s until now. Figure (6) shows the reclamation divided into two stages, one during the 60�s and the second starting late 70�s until now (Hamed, 1996).

Over two million feddans are available for future reclamation in the oases and East Owaynat and its land classification is divided into two priorities based on its soil properties as shown in figure (7) (Nour, 1995). Deep groundwater is available in the oases and East Owaynat with huge quantities but economical lifting depth from the wells on the long run, will determine the economical visibility of reclamation.

Figure (8) shows the potential of groundwater extraction with the economical lifting depth, present extraction rate and the average water depth after 100 year (Nour, 1995). It is proposed, in the national horizontal expansion plan, to reclaime 500,000 feddans in the first stage through the year 2017.

For the determination of the canal location upstream or down stream the High Dam, five proposed routes for the canal were studied and compared. From the comparison it is clear that route (3) of Qena/El -kharga/Abu Tarour and route (4) of Aswan/Khafraa/Paris are extremely long (about 400 Kilometers) and exceed the estimated cost of the other routes. Route (1) of Assiut/El-Kharga and route (2) of Esna/El-Kharga crosses a series of plateaus and hills, which require a high pumping cost. On the contrary, the selected route (5) for withdrawing water from Lake Nasser upstream the High Dam is proven to be the best alternative because of the natural land slope from the beginning of the main canal and its end. Also, this route saves energy by lifting water from the Lake where energy cost gets lower as water level in the Lake gets higher. In addition, it is estimated that this route have the lowest quantities of soil excavation compared to the other four routes.

Comparing the two proposed routes for Sheikh Zayed branch canals, it is recommended to choose the second alternative because its canals passes through the middle of the chosen canal command area boundaries which gives a better distribution of water to the right and left of the canal through the head regulators. Als, the length of branch canal (4) is longer to cover a bigger portion of the branch canal command area.

The area climate of Southern Egypt is considered a very dry tropical arid with almost no rainfall and that raises the water requirements per feddan to about 9000-11,000 m³/fed/yr. This water requirement is very high compared to the water requirements in the Delta of about 6000-7000 m³/fed/yr. Drainage reuse requires more study to determine the locations of reuse pump stations and the drainage collection lakes.

Nour, Said Saleh, 1995. �Master Plan for using groundwater in the Western Desert areas�, The conference of groundwater Map in Egypt, Cairo, Egypt.

Hamad, Sabri Mohamed, 1996. �Toward a new development strategy for the Western Desert �, The conference of desert development, Cairo, Egypt.

Ministry of Public Works and Water Resources, 1997. �Development of southern Egypt, the New Valley canal Project�, Cairo, Egypt.

Mouselhy, Fathy Mohamed, 1996. �Toward a global strategy for desert development by evaluating recent projects�, The conference of desert development, Cairo Egypt.

Horizontal Expansion Sector, 1997. �National horizontal reclamation project of 3.4 million feddans through the year 2017�, Ministry of Public Works and Water Resources Publications, Cairo, Egypt.

Ministry of Public Works and Water Resources, 1997. �South Egypt development project�, Ministry of Public Works and Water Resources publications, Cairo, Egypt.

Dr. Nagy G. R. Yakoub

Researcher, Head of the GIS Central Unit

National Water Research Center

Fum Ismalia Canal, P.O. Box 74

Shoubra El-Kheima 13411

Cairo, Egypt

Tel: (202) 222-6762

Fax: (202) 222-6761

E-mail: NWRC @ IDSC. GOV. EG

Dr. Mona El Kady

Chairman of the National Water Research Center

National Water Research Center

Fum Ismalia Canal, P.O. Box 74

Shoubra El-Kheima 13411

Cairo, Egypt

Tel: (202) 222-6762

Fax: (202) 222-6761

E-mail: NWRC @ IDSC. GOV. EG