Technical details
The dam is designed to have a length of about 9 km (5.6 mi) and a crest height of up to 67 m (220 ft). It will consist of polystyrene-faced rockfill dams on each river bank, an earth-rock dam with a pepper core in the left river channel and a live water section in the right river channel (sluices, spillway and power intake dam with turbine housings). Once finished, it will contain a reservoir of 12.5 km3 (3.0 cu mi), or about 20% of the Nile's annual flow. The reservoir lake is planned to extend 174 km (108 mi) upstream.The powerhouse will be equipped with ten 125 MW Francis turbines, each one designed for a nominal discharge rate of 300 m/s (980 ft/s), and each one driving a 150 MVA, 15 kV synchronous generator. The planners expect an annual electricity yield of 5.5 TWh, corresponding to an average load of 625 MW, or 50% of the rated load. To utilize the extra generation capacity, the Sudanese power grid will be upgraded and extended as part of the project. It is planned to build about 500 km (310 mi) of new 500 kV aerial transmission line across the Bayudah desert to Atbara, continuing to Omdurman/Khartoum, as well as about 1,000 km (620 mi) of 220 kV lines eastwards to Port Sudan and westwards along the Nile, connecting to Merowe, Dabba and Dongola.
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Planning and construction
The idea of a Nile dam at the 4th cataract is quite old. The authorities of the Anglo-Egyptian Sudan proposed it several times during the first half of the 20th century. It was supposed to equalize the large annual Nile flow fluctuations, create the possibility of growing cotton and provide flood protection for the lower Nile valley. After Sudan achieved independence in 1956, Egypt finally decided to control the Nile floods with a dam and reservoir on its own territory—the Aswan Dam and Nasser Lake.
The military government under President Nimeiri revived the plan in 1979, now with the intention of producing hydroelectricity for Sudan's rising demand. The following decade saw international industry and planning offices busy, producing a total of four feasibility studies [1 - Coyne et Bellier, 1979 / Gibb, Merz & McLellan, GB, 1983 / Sweco, SE, 1984 / Monenco Consultants Ltd., CA, 1989]. However, insufficient funding and lack of investor interest effectively stalled the project at the planning stage.
This appears to have changed fundamentally since the country started exporting oil in commercial quantities in the years 1999/2000. A greatly improved creditworthiness brought an influx of foreign investment, and the contracts for the construction of what is now known as the Merowe Dam project were signed in 2002 and 2003.
The main contractors are:
- China International Water&Electric Corp., China National Water Resources and Hydropower Engineering Corp. (construction of dam, hydromechanical works)
- Lahmeyer International (Germany - planning, project management, civil engineering)
- Alstom (France - generators, turbines)
- Harbin Power Engineering Company, Jilin Province Transmission and Substation Project Company (both China - transmission system extension)
River diversion and work on the concrete dams began in early 2004. The project timeline schedules the reservoir impounding to start in mid-2006 and the first generating unit to go on-line in mid-2007. The work will be finished when the water level in the reservoir will have reached 300 m (980 ft) above MSL and all ten generating units will be operational, scheduled for 2009. The dam was inaugurated on March 3, 2009.
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Financing
The total project cost is reported to be €1.2 billion. This can be subdivided into partial amounts for the construction work on the dam itself (ca. 45%), its technical equipment (ca. 25%) and the necessary upgrade of the power transmission system (ca. 30%). The project receives funding from- China Import Export Bank - approx. EUR 240 million
- Arab Fund for Economic and Social Development – approx. EUR 130 million
- Saudi Fund for Development – approx. EUR 130 million
- Oman Fund for Development - approx. EUR 130 million
- Abu Dhabi Fund for Development – approx. EUR 85 million
- Kuwait Fund for Arab Economic Development – approx. EUR 85 million
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Benefits
The electrification level in Sudan is very low, even by the standards of the region. In 2002, the average Sudanese consumed 58 kWh of electricity per year [1], i.e., about one fifteenth of their Egyptian neighbors to the north, and less than one hundredth of the OECD average. The capital Khartoum and a few large plantations account for more than two thirds of the country's electric power demand, while most of the rural areas are not connected to the national grid. Many villages use the option of connecting small generators to the ubiquitous diesel-powered irrigation pumps. This way of generating electricity is rather inefficient and expensive.The combined grid-connected generating capacity in Sudan was 728 MW in 2002, about 45% hydroelectricity and 55% oil-fired thermal plants. However, the effective capacity has always been a lot lower. The two main facilities, the Sennar (constructed in 1925) and Roseires (1966) dams on the Blue Nile, were originally designed for irrigation purposes rather than power production. Generating units were added during the 1960s and 1970s when the demand for electric power increased, but their power production is often heavily restricted by irrigation needs.
The government in Khartoum has announced plans to raise the country's electrification level from an estimated 30% to about 90% in the mid-term [2]. Large investments into the medium and low voltage distribution grids will be necessary but not sufficient to reach this ambitious goal: First and foremost, the foreseeable increase in power consumption would require the addition of generating capacity. During the 1990s, Sudanese electricity customers have already been plagued by frequent blackouts and brownouts due to insufficient generation. Three new thermal power plants went into operation in the Khartoum area in 2004, increasing the installed capacity to 1315 MW. The Merowe dam with its peak output of 1250 MW will almost double this capacity once it comes online.
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Human impact
Resettlement
Before the construction began, an estimated 55,000 to 70,000 people were residents of the area which will be covered by the reservoir lake, mainly belonging to the Manasir, Hamadab and Amri tribes. They settle in small farming villages along the banks of the Nile and on the islands in the cataract. The whole region is relatively isolated, without paved roads or other infrastructure, and the communities are widely self-sufficient. Except for beans and millet the farmers grow vegetables, both for their own consumption and for trading at the weekly regional markets. However, their main source of income—and their most valuable possession—are the groves of date palms growing in the fertile silt on the river banks.Once the dam is completed and the reservoir impounding begins, the whole population will be forced to move. While the majority of the farmers would prefer to stay as close to their old grounds as possible and build themselves a new existence at the shores of the new lake, the government has decided otherwise and pointed out three resettlement sites: Al-Multaqah, Al-Makabrab and Al-Muqadam. At these locations, farmers will receive plots of land relative in size to their former possessions, in addition to financial compensation for lost assets—houses and date palms.[2]
Though government officials claim there are improved living conditions at the resettlement areas, with relatively modern buildings and infrastructure, the affected people reject the compensation plans. Their main objections are:
- The soil at the resettlement areas is sandy, and its quality is extremely poor, particularly if compared to the excellent farmland by the Nile. It would take much effort and a long time—probably decades—until it became fertile enough for growing vegetables and other marketable produce.
- The government has announced that it will provide free water supply, sand removal and fertilizer during the first two years after the resettlement [3]. After this period, the farmers will have to pay the full price for these services, none of which had to be used at the old site.
- Compensation for a date palm amounts to about four years' harvest, while a good palm tree can bear fruit for a hundred years. Compensation for vegetable gardens is very low, and only married men will receive compensation for their houses[citation needed].
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Nomads
A significant fraction of the Manasir tribe inhabits the desert regions close to the Nile valley. The exact size of this nomadic population is unknown, but estimated to be of the same order of magnitude as that of the resident farmers, i.e., tens of thousands. Both groups maintain tight cultural interchanges and trade relations with each other.Only the owners of real estate purportedly are covered under the compensation scheme[citation needed], although reports are that families have been displaced without compensation or adequate provisions for relocation. Nomadic families will not receive any compensation, even though the resettlement of the farming Manasir will deprive them of their symbiotic partners. The consequences for their ability to sustain their lives in a harsh environment remain to be assessed.
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Human rights concerns and fears of another war
UN Special Rapporteur on Adequate Housing Miloon Kothari issued a statement August 27,[2007], calling for a halt to dam construction at Merowe until an independent assessment of the dam's impacts on the more than 60,000 people who stand to be displaced by the dams at Merowe and Kajbar. Kothari stated he has "received reports that the Merowe reservoir’s water levels have already risen, destroying dozens of homes in the area and putting many more at risk."[4]Kothari announced, "The affected people have claimed that they received no warning that water levels would be raised and that no assistance from Government authorities has been forthcoming since their houses were destroyed." According to reports, the Government of Sudan has not honored its promises to those who have been displaced. Kothari noted that, "thousands of people in the same area were relocated in similar circumstances that left many temporarily without food or shelter, and that some of those people remain homeless today."[5] Kothari called upon the Sudanese government to ensure safety and adequate housing to all those affected by the dams and warned the projects "would lead to large-scale forced evictions and further violence."
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Archaeology
The fertile Nile valley has been attracting human settlement for thousands of years. The section between the 4th and 5th cataract—a significant portion of which will be inundated by the reservoir lake—has been densely populated through nearly all periods of (pre)history, but very little archaeological work has ever been conducted in this particular region. Recent surveys have confirmed the richness and diversity of traceable remains, from the Stone Age to the Islamic period.Several foreign institutions have been recently or are currently involved in salvage archaeology in the region, among them the ACACIA project University of Cologne, Gdańsk Archaeological Museum Expedition (GAME), Polish Academy of Sciences, Humboldt University of Berlin, the Italian Institute for Africa and the Orient (IsIAO), the University College London, the Sudan Archaeological Research Society, the Hungarian Meroe Foundation, University of California at Santa Barbara - Arizona State University consortium, and the Oriental Institute Museum of the University of Chicago.
Their main problems are the shortness of the remaining time and limited funding. Unlike the large UNESCO campaign conducted in Egypt before the completion of the Aswan High Dam, when more than a thousand archaeological sites could be documented and complete buildings were moved to prevent them from drowning in Lake Nasser's floods, work at the 4th cararact is much more restricted.
Historian Runoko Rashidi recently issued a statement in solidarity with Sudanese Nubians protesting the dams and called for a halt to their construction.
.We have never forgotten the terrible tragedy resulting from the Aswan High Dam in Egyptian Nubia. The project in Sudanese Nubia, which we call the "damn dams", will perpetuate yet another tragedy, another atrocity, against African people. Nubia is a treasure-house of artifacts that attest to the ancient greatness of Africa. For it to be inundated will cause irreparable harm to a noble heritage.
We must organize to resist this project. One of the great figures among Africans in America, Frederick Douglass, said that "power concedes nothing without demand. It never did, and it never will."
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