lunes, 23 de mayo de 2011

Artículo No. 32 Saudi ARAMCO World Libya s water Regional and National Efforts

The four NSAS countries have all signed up to the international Convention on Biodiversity and the United Nations Convention to Combat Desertification. In 1992, the ‘Joint Authority for the Management of the NSAS System’ was created by the four Nubian countries to enhance cooperation in managing NSAS water resources. The IAEA has and continues to work with NSAS countries to address water resource management issues through national, multi-country regional projects — foundations for the larger ‘Nubian Project’.

International initiatives

The four countries of the NSAS have all signed up for international initiatives geared to better understanding and resolving environmental issues affecting them. Each country signed and ratified the international Convention on Biodiversity (CBD) geared to the conservation of biodiversity, sustainable use and sharing the benefits arising from the commercial and other utilization of genetic resources in a fair and equitable way.
Connected to this, Chad and Egypt have completed National Biodiversity Plans underlining the importance of protecting oases ecosystems. For example, Egypt aims to designate oases in its Western Desert as protected areas while Chad aims to re-introduce plants that have disappeared from arid areas such as the Logoni Basin. All four countries also signed and ratified the United Nations Convention to Combat Desertification (UNCCD) which aims to promote effective action through innovative local programmes and supportive international partnerships. National strategies have also been or are being developed. For example, in Egypt´s National Plan to Combat Desertification, groundwater resources will be used in measures to grow natural buffers to stop the advancement of desert dunes advancing and threatening the Kharga and Farafra oasis communities and palm plantations. Similar measures can also be found in Chad and Libya.

The ‘Joint Authority’

In the early 1970s, Egypt and Libya initiated a process for the four NSAS countries to start cooperating in managing NSAS water resources. In 1992, it was formalized with the creation of the Joint Authority for the Management of the NSAS System. Sudan joined in 1996 and Chad followed in 1999. Its original objectives were to oversee strategic planning, develop an NSAS monitoring programme and exchange data and information on water resources and extraction.
The respective National Project Coordinator (NPC) institutions for the Joint Authority are the Research Institute for Groundwater in Egypt, the General Water Authority of the Secretariat of Agriculture in Libya, the Groundwater and Wadis Directorate in Sudan and the Direction de l‘Hydraulique of MEE in Chad. Successes include an agreement to develop a regional monitoring network with 60 existing wells and 14 recommended new wells. A regional strategy assessed the future impacts from extractions and made recommendations for minimizing impacts. Socio-economic aspects were also proposed to address theharmonisation of groundwater access and availability between regions, improve the understanding of and communication with indigenous communities, and adapt development plans to local conditions.
This cooperation was activated from 1997–2002 through baseline activities supported by the International Fund for Agricultural Development (IFAD) under the project management of the inter-regional organization, the Centre for Environment and Development for the Arab Region and Europe (CEDARE). This resulted in a joint survey of the socio-economic development policies and plans in the aquifer areas and the establishment of the NSAS Regional Information System (NARIS) database. NARIS modelling scenarios provided initial indications of the impacts on water levels and water quality over a sample period of 60 years of development and abstractions, while the model still needs to be adapted for operational use. The Nubian countries are currently planning for the expansion of aquifer monitoring and observation well networks. There remain, however, significant data and capacity gaps.

Regional IAEA assistance

The International Atomic Energy Agency (IAEA) is currently actively cooperating with countries in the NSAS region to address water resource management issues through multi-country projects. It is a cooperating partner and co-funder in the UNEP/OSS/GEF ‘IullemedenAquifer Project’ and UNEP/OSS/GEF ‘Northern Sahara Aquifer Project’.
It is also providing technical assistance to Nile Basin countries to develop a more accurate, complete water balance there. Since March 2003, the IAEA has also been funding and working with Egypt, Libya and Sudanon a regional project entitled ‘Towards a Sustainable Development of the Nubian Aquifer’. With five goals, its first goal is to expand and consolidate the technical and scientific knowledge base regarding the aquifer system including the development of an appropriate model using isotope techniques. Its second is to develop and strengthen a joint Nubian Aquifer Management Framework to guide water use and build international cooperation. Its third and fourth are to develop links and networks between international and national organizations as well as a public participation and communication plan. Finally, it also seeks to explain past damages to ecosystems and design ways to prevent further future damage. The regional project, and other IAEA efforts at the national level, helped to improve overall understanding of the NSAS and to set the basis for the much broader current ‘Nubian Project’.

National efforts

To date, all of the NSAS countries have planned and implemented activities geared at better understanding their groundwater resources and how to exploit them, in some cases through projects with the IAEA. For example, the IAEA is currently helping Sudan to assess the origins of pollution, especially from organic fertilizers, pesticides, landfill leakage and human sewage, entering the ‘Khartoum Aquifer’, a reserve that has contact with the NSAS.
Recent efforts by Egypt´s government to better understand NSAS resources include the development of methodologies for the desalination of brackish groundwater, artificial recharge and for storing water for drinking, industrial and agricultural uses. Egypt is also installing 15 observation wells in the southern part of the NSAS. Past collaboration with the IAEA included groundwater assessments in the Western Desert to help the government make its population redistribution program there more sustainable.
Libyan Arab Jamahiriya (Libya)
A current IAEA project is using isotope hydrology to better understand the impacts of water abstraction from the Kufra and Sarir sub-basin sections of the NSAS for the purpose of piping water to coastal areas. Efforts will address concerns about how abstraction might deteriorate water quality through the mobilisation of saline groundwater. The project is also looking into questions of recharge, connectivity and age determination.
A number of IAEA-assisted technical cooperation projects have been executed for many years in Sudan, mainly to investigate the influence of the Nile River system and large seasonal wadis on adjacent parts of the NSAS. Results from IAEA isotope studies contributed to an improved understanding of the sources and origins of water, hydraulic interconnections between aquifer units, groundwater recharge, the sources and processes of water salinization and identification of pollution sources and their transport dynamics. While information gathered has been useful (e.g. for updating hydro-geological maps), there is still an urgent need for additional isotopic investigations in the NSAS area and other parts of Sudan. A new IAEA project is helpingSudan to assess the origins of pollution, especially from organic fertilizers, pesticides, landfill leakage and human sewage, entering the ‘Khartoum Aquifer’, a reserve in contact with the NSAS.
Some preliminary research has been carried out on the geology and hydrogeology of Chad. National authorities have adopted a national water resources strategy to investigate the possibility of introducing state-of-the art technology to extract groundwater from aquifers. Initially, this will involve the drilling of boreholes and the setting up of modern pumping systems that will require large financial and human resources. Funds are now being sought. Sites for monitoring wells in the NSAS area have also been identified based on existing springs and wells. Before the Nubian Project began, there were no IAEA activities in Chad.
Because the Nubian Aquifer is shared among four nations, and because Libya and Egypt are now going forward with big water-pumping projects that tap the Nubian Aquifer, the International Atomic Energy Agency (IAEA), co-recipient of the 2005 Nobel Peace Prize, is trying to bring the countries together in a joint effort to plan for a rational shared use of the water.
Nuclear scientists are leading the way now, but sometime in the future diplomats may be signing aquifer-sharing treaties similar to those that now commonly control the sharing of surface waters. Such a treaty allots the Nile River’s flow among Ethiopia, Sudan and Egypt. Esmat AbdelMeguid, former secretary-general of the Arab League and Egyptian foreign minister, likes the sound of the words diplomacy and hydrology in the same sentence. “International agreements are the only way to go, especially among thirsty neighbors who live in the desert,” he says.
Dr. Aly Islam, chairman of the Egyptian Atomic Energy Authority (EAEA), whose isotope-hydrology laboratory in Cairo is a key asset in the project, has an even sharper perspective on the subject of “atoms for peace.” “Mankind’s use of nuclear science to date has been rather sad,” he says. “But if we who specialize in the atom can dedicate ourselves to peaceful ends, like water analysis, or seed research, or even irradiating semiprecious gems to make them more beautiful, then we will have done our part.” Dr. Islam is himself a world expert in the nitrogen-15 isotope, used for water-pollution studies.
The stakes are certainly high. Although the population density of the area overlying the aquifer is less than one person per square kilometer (2.6 people per square mile)—1/2000 that of the populous Nile Valley—desert agriculture and resettlement plans dating from the 1960’s are being dusted off. Egypt eventually hopes to use almost half a billion cubic meters of groundwater annually—more than the volume of Lake Erie. Libya is already pumping water from the Kufra Oasis, in its southeast corner, through a four-meter-diameter pipeline to its thirsty coastal cities. When fully operational, that project will pump some 3.6 million cubic meters per day. Still, at current extraction rates, the aquifer is not likely to be depleted for a thousand years.
Kufra lies not far across the border from Egypt’s East Uweinat agriculture project, which itself is just north ofSudan’s Salima Oasis, whose soils have proved high fertility. Farther north, Libya’s Al-Jaghboub Oasis and Egypt’sSiwa Oasis are pumping from the aquifer’s same limited sub-basin. Even northern Chad’s 3415-meter-high TibestiMassif, where any development plans are far in the future, is critical to what little rainfall does recharge the aquifer in southern Libya and Egypt. In the region where the four countries touch, everything underground seems connected
The EAEA’s isotope hydrology lab, filled with high-tech machinery and directed by Dr. Sawsan Abd El-Samie, is a long way from the blazing desert. But water from that desert is tested here and compared to previously quantified international samples, supplied through the IAEA by the United States Geological Survey in tiny vials labeled with such far-off names as “Antarctic Water 1” and “Puerto Rico Water 1.” The machine that does the comparisons, an isotopic ratio mass spectrometer, is periodically recalibrated against the IAEA standard, known as VSMOW, or “Vienna Standard Mean Ocean Water.”
Abd El-Samie and her team go about the task of purifying and maximizing the component gases that she squeezes out of her water samples, using extreme heating and cooling and vacuum pressurizing to a tiny fraction of normal atmospheric pressure. “Sample purity is essential when we work at the atomic level,” she says, “and we must check and recheck for anomalies. Sometimes our irrigation-engineer colleagues do not understand why they must protect a sample against contamination—they think water is always just water.”
Abd El-Samie is looking for oxygen and hydrogen atoms with extra neutrons in their nuclei; such atoms act as markers, or fingerprints, for that particular sample and can give a relative timeline for the groundwater’s deposition. Water sampled at different depths acts almost like a rain-gauge record that goes back tens of thousands of years.
Another machine, the liquid scintillator, looks for the sample’s carbon-14 isotope, which attaches to water molecules in the sky when cosmic rays strike. Since carbon-14 is an unstable isotope with a known half-life, it can be measured and dated with some accuracy. But the scintillator is a thirsty machine: It usually takes a 60-liter water sample to yield just 300 milligrams of testable carbonate.
The project’s reach extends from the laboratory to the desert, with an intermediate stop at the Groundwater Research Institute, part of the National Water Research Center under Egypt’s Ministry of Water Resources and Irrigation. This is the core of the nation’s irrigation know-how, which stretches back some 5000 years. The center is located, appropriately, at the Nile Barrage just north of Cairo, where engineering works divide the two branches of the Nile and provide a testament to Egypt’s long history of manipulating the flow of water.
Dr. Taher Muhammad Hassan is charged with pulling together all the project’s many strands, from isotope laboratory results to piezometer (well-pressure) readings, from geological maps to the resettlement dreams of social policymakers. “We know some things about the Nubian Aquifer but many other things we do not,” he says. “The aquifer is what we call a closed system, but within it there are many internal dynamics—sub-basins and drainages, impermeable clay layers, vertical faults and horizontal fissures, and a limited potential for local recharge. And everything is deep underground, far out of sight.”
He gives the example of the Great Sand Sea, the dune system between Egypt and Libya west of FarafraOasis. Eighteen-meter dunes overlie a layer of clay, which may hold a large isolated reservoir, a perched water table. Ground-penetrating radar indicates something is there, not far from the surface—but how to access it and, given the rough topography and poor soil conditions, why bother? “Not now,” says Hassan with a smile. “But maybe later.”
“One thing that isotope studies have shown us,” Hassan continues, “is that there is surprising little aquifer recharge from the Nile. Nile water has a younger isotopic profile, and samples from wells dug as close as five kilometers from the river show no sign of the Nile fingerprint. In fact, some of that well water is dated at 26,000 years old.” Since scientists now know they cannot rely on passive recharge taking place naturally, they might engineer it artificially, channeling water from the Toshka emergency spillway, just north of Abu Simbel, toward Kharga Oasis and helping it to enter the aquifer there by digging infiltration basins, injection (pumped) wells and gravity (percolation) wells.
“We had a huge Nile flood in 1996,” says Hassan, “and 33 billion cubic meters of river water filled the Toshka depression, just 50 kilometers from Kharga, where it has been evaporating ever since at a rate of three billion cubic meters each year. Now we have salt marshes there, good for duck hunting but not much else.”
 alt="Once the well is ready for testing, the ministry engineers check its static and dynamic levels with a sounder, a kind of fisherman’s bob at the end of a tape measure that rises and falls with the water table.">
Hassan is confident there is little likelihood of international conflict over aquifer sharing. “We know that the velocity of underground flow in most places is just two meters a day,” he says. “It’s like sucking a thick milkshake through a straw—it doesn’t happen fast, and eventually it stops completely.” Even Libya’s big extraction plans forKufra will probably have only a minor effect on Egypt’s East Uweinat farming area, given the distance between the two. If Kufra’s water table drops 200 meters, the Egyptian side might see a drop of only 10 centimeters.
Such confidence does not travel very far, however. In the Bahariyya Oasis, a five-hour drive southwest of Cairo out past the Pyramids, the famous Roman spring called Bishmu has gone dry in recent memory due to over-pumping from nearby wells. The oasis has some 75 government-dug deep wells and hundreds of privately dug shallow wells. Because Bahariyyais a geological uplift, comprising limestone underlaid here by sandstone, some of the aquifer’s 30-odd horizons, or distinct water-bearing rock strata, are near the surface; some wells are thus free-flowing and require no mechanical lifting.
Sixty-five-year-old Abdel Min’am Hasaballah, who farms 12 feddans (roughly 12 acres) of wheat, barley, alfalfa and date palms, relies on a nearby 1000-meter-deep government well to allocate him 11 hours of water in each 15-day irrigation cycle, called a dawrah. Before the construction of the Aswan High Dam, his father dug a 100-meter free-flowing well which subsequently went dry in this long-farmed part of the oasis. Abdel Min’am blames the deep well’s hot 50°C (122°F) water for killing his apricot trees—which may be true—and also blames the dam for knocking the hydrology of the oasis off-kilter, which is less accurate.
More likely his father’s problem stemmed from the steady reclamation of thirsty new lands on the oasis’s margins. Not far away, Talaat Abdel Bari works as a contract well-digger, using the free-spinning wheel of an old tractor set on blocks to power a pipe-driving hammer. He charges small farmers $10 per meter of well depth ($3.05 per foot); by 70 meters’ depth he usually strikes water that will free-flow at a rate of 10 cubic meters per hour—just about right to irrigate this client’s eight feddans. Each feddan requires about 25 cubic meters per day, depending on the crop mix. Even if a well goes dry after five years of steadily decreasing flow, a farmer will have profited from the investment, and need only sink another well close enough to the first one to use the same irrigation channels.
Ministry of Irrigation engineer Ibrahim Salama oversees the drilling of deep government wells such as that currently being dug at al-Agouza West. A 10-story drilling rig, the same kind used to drill oil wells, has reached 800 meters and is now evacuating the drilling mud and widening the bore. It has taken 20 days to penetrate layers of shale and clay to reach the saturated sandstone—the basement of the Nubian formation is some 1800 meters deep here—at a cost of about $400,000.
Samples are taken every 10 meters for analysis. Because the northern half of the Nubian Aquifer is overlaid with limestone layers which carry brackish water containing up to 8000 parts per million (ppm) of dissolved salts, wells in this zone must drill through them in order to reach the sandstone’s sweeter water, containing only 200 ppm.
Once the well is ready for testing, the ministry engineers check its static and dynamic levels with a sounder, a kind of fisherman’s bob at the end of a tape measure that rises and falls with the water table. The static level is the water’s depth under natural conditions; the dynamic level measures its drop when water is pumped out at varying rates, say 100 or 200 cubic meters an hour. Under the new project, information from the well drillers—geochemistry, lithography and hydrology—will be fed into a database married to the isotope readings from special test wells that will help to penetrate the aquifer’s deeper secrets
A first draft of such a database, lacking only the isotope readings, has been built by the Egyptian non-profit Center for Environment and Development of the Arab Region and Europe (CEDARE). CalledNARIS, for “Nubian Aquifer Regional Information System,” the database is a computer-based display of hydrological maps, water-use scenarios and long- term projections.
CEDARE water-resources manager Dr. Khaled Abu Zeid notes that much of the NARIS data was collected through the Joint Authority for the Nubian Aquifer, an international office headquartered in Tripoli that was established by the Libyan and Egyptian governments in 1992 and joined a few years later by Sudan and Chad. “It was not a very systematic approach, but at least it was a beginning,” says AbuZeid.
He stresses the social context of water-resource development, and the need to keep in mind traditional water users as well as new users. Small farmers and Bedouin who rely on shallow wells should not be ignored in favor of the big development schemes. “They need water today,” he says, “and will still need it tomorrow. We must not let it run dry because deeper wells are more cost-effective. But neither should we have an absolutist conservationist approach, in which we try to keep fossil water in some kind of ‘museum’ for their benefit.”
Abu Zeid might have been thinking of Rifaat Sayyid Hamida and his brother Atef in Bahariyya. Although not traditional users in the full sense—Rifaat is an accountant, Atef is an English teacher, and both are weekend farmers—their roots here go back many generations, and their grandfather was a full-time date grower in the old farms of the oasis. Eight years ago, feeling a need to “return to the land,” they bought 11 feddans of reclaimed desert, paid $2600 for a 130-meter free-flowing well, and now farm apricots, grapes and alfalfa. Their seven sons are learning to do as a hobby what their great-grandfather once did by necessity.
Dr. Ahmed Khater, director of the Groundwater Research Institute at the Nile Barrage, finds it ironic that in a desert region like the Middle East, petroleum geology is much better understood than subsurface hydrology. “But water is what makes our life possible here, and we must use it wisely,” he says. He cites the experience of President Nasser’s “New Valley” project in the 1960’s, which proposed a massive resettlement of Nile Valley farmers to the western oases. It was a failure.
“These isotope studies hold the promise of learning more about what is really our most precious asset—water, not oil,” he says. Nasser, he notes, got the New Valley project’s motto wrong. “He said, ‘When settlers come, then we will find water,’” says Khater. “He should have said, ‘When we find water, then settlers can come.’”

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