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3.3 Sag el Na'am irrigation project (northern Darfur).


The Sag el Na'am project is the only major agricultural development project in Northern Darfur. It was introduced to a region with very limited development potential to provide a nucleus of economic activities based on irrigated agricultural production for 420 families. The livelihood of the population, which is expected to increase to 3.00 3,500 in total, was to be secured through the cultivation of aura. dukhn, and summer pulses, as well as wheat and winter pulses. In addition, a wide variety of other crops. including vegetables, citrus, and forage, was to be grown to stabilize the local supply of essential food and feed products.

The project has political importance to demonstrate the desire of the government to support local initiative of the population to remain in marginal areas, despite the high costs involved. From the beginning it was clear that exceptionally high pumping costs. because of the very deep aquifer, had to be justified by results mainly on social and equity grounds, not on economic or financial ones. In this light, the main objective of the project can be considered to be the minimizing of the costs of production at Sag el Na'am to a point which balances the financial losses of the government with the private and social benefits for the population involved.

3.3.1 Performance Analysis

The project is based upon the ground-water reservoir of the Alauna Basin, which suffers from the major disadvantage that the static water level lies about 90 meters below the surface. Pumping is therefore exceptionally expensive. Despite the very high pumping costs. a decision to proceed with a pilot scheme was taken during the early 1970s. Three wells were equipped with 100 m/ha capacity pumps in time to irrigate 125 feddans during the 1975 kharif (rainy) season, and further development allowed 300 feddans to be irrigated in the following shita (winter) season. Forty 180 m/ha capacity pumps have been ordered, and by June 1976 the drilling programme in preparation for these pumps was 50 per cent complete. When these pumps are fully installed. the irrigated area will increase to just under 3,000 feddans.

The main crops grown during 1975/76 were aura (sorghum), wheat, and pulses, together with a wide range of vegetables and other minor crops. Field irrigation is based upon the traditional Angaia system (practiced elsewhere in the Sudan), with each well command divided into units of five feddans each. The main disadvantage of the present layout is its unsuitability for mechanized farming. and the failure to measure the amount of water pumped must also be considered a major deficiency.

Despite these and a few other drawbacks, the development and subsequent management of the project has been impressive. The scale of development has, however, so far been small and with expansion, a number of problems can be expected to emerge:
a) Pumping abstractions may approach or exceed the safe yield.
b) Continuous cultivation of the Sag el Na'am soils could lead to fertility and salinity problems.
c) It may prove difficult to maintain delivery of fuel and other supplies, given the project's isolation. d) The limited markets of Northern Darfur and the great distances to other markets will increasingly affect the ease with which agricultural output can be sold.
e) Managerial, maintenance, and operational problems will increase with scale of operations, and particular difficulties could be associated with the initiation of a settler scheme.
f) Budgetary constraints may become serious since the exceptionally high pumping costs and other factors will necessitate a rapid increase in the level of subsidy.

TABLE 11. Major Development Characteristics at Project Maturity in Sag el Na'am

  Rated Discharge
100 m/ha
Capacity of Pumps
180 m/ha
Well Commands (No.) 3 40
Area Irrigated (feddans)    
Summer pulse/winter cereal a - 1 200
Summer cereal/winter pulse a - 900
Summer forage/winter cereal b - 120
Perennial forage/summer cereal b - 140
Horticultureb - 80
Settler garden plotsa - 236
Total area 130b 2 676
Water Extraction (million cubic meters)  
Summer season (kharif) - 13.54
Winter season (shita) - 9.27
Total amount 0.92 22.81
Fuel Consumption (Imperial gallons/year) 54000 693 000

Source: HTS. Sag el Na 'am Evaluation. 1976. p. xii.
a. Settler areas.
b. Areas operated using directly employed labour.

TABLE 12. Capital Cost Estimates: Forty 180 m/ha Capacity Pump Programme (in thousands of S)

Yeara 1975/76 1976/77 1977/78 1978/79 1979/80 1980/81
Well construction 363.8 218.3 0.0 0.0 0.0 0.0
Pumps 79.6 161.0 115.4 79.7 73.9 68.2
Subtotal 443.4 379.3 115.4 79.7 73.9 68.2
Other capital costs b 68.6 116.7 63.4 7.9 0.5 0.0
Total capital costs 511.9 496.0 178.8 87.6 74.4 68.2
Foreign exchange portion of capital costs 350.0 281.7 117.7 81.3 74.0 68.2

Source: HTS, Sag el Na 'am Evaluation. 1976. p. xiv.
a. Financial year to the end of June.
b. Including principal repayments and interest charges.

The overall limits of this programme are based upon the current intentions of the Ministry of Agriculture. The estimates can be discussed as follows:
a) Tenant farmers will be settled on 35 commands, cultivating two main cereal/pulse rotations and subsidiary garden plots. There are few demand constraints on the main summer crops (sorghum, millet, and groundnuts), but after allowing for pumping costs, the returns, especially for the cereals, are heavily negative. In contrast, the winter pulses. and to a lesser extent wheat. face limited markets but provide relatively favourable returns.
b) Labour employed directly by the project will be used for forage, horticulture (other than on garden plots). and the units commanded by the 100m/ ha pumps, the latter being cropped as at present. Horticulture is relatively profitable but faces severely limited markets. Forage production gives a heavily negative return but is included for general developmental purposes.
c) Water extraction will rise to an estimated 23.7 million cubic meters per year. which is close to the estimated safe yield. Any expansion beyond this programme would therefore run the risk of mining the aquifer with a consequent continuous increase in the pumping costs.
d) Fuel requirements will rise to about 750,000 imperial gallons. The project will therefore require almost four times as much diesel as the total current needs of the province of Northern Darfur.
e) Each settler family will have five feddans of main crops and half a feddan of garden crops. This would result in the settlement of 420 families upon completion of the programme. Allowing for dependents and a direct labour force of 20 250, the total population in the scheme could rise to about 3,500. giving rise to a demand for housing, education. and other services.

Table 12 summarizes the estimated capital costs of the programme for the construction of 40 wells equipped with larger 180 m/ha pumps. It excludes the costs associated with the smaller pumps and aims to be representative of any further expansion. The phasing assumes that all the wells will be constructed by the end of 1976/77 but that the pumps, although delivered in 1976/77, will not be fully operational until the 1979 kharif season. The payment schedule agreed upon with the pump suppliers forms the basis for the estimate given. Other capital costs include canalization. buildings, vehicles, and equipment. An element for engineering and supervision is included in wellconstruction costs, although this is on the conservative side and may understate actual charges of the Rural Water Corporation.

Table 13 summarizes the economic analysis for the forty 180 m/ha capacity pump programme. Costs and returns are adjusted to reflect their real resource cost to the national economy through the exclusion of taxes and reflect the lack of other work opportunities during the dry season. The opportunity cost of capital is taken to be 8 per cent and the project life to be twenty years, with the pumps being replaced after ten years. Overhead costs include those costs which cannot be attributed to particular agricultural activities (for instance, management costs). Agricultural returns are given for both the present system of agriculture and for a possible system assuming that high yields are achieved (for instance, through the use of fertilizer). In practice, settlers are unlikely to achieve a level of agriculture much above that achieved at present. The increase in agricultural activities reflects the development schedule discussed earlier.

TABLE 13. Summary of Economic Analyses:.a Forty 180 m/h Capacity Pump Programme (in thousands of S)

  Present Value in 1975/76 at 8 per cent
  Present System Intensive System
Capital costs b -1 415 - 1 415
Overhead costs -455 - 455
Irrigation costs -2 909 - 2 909
Net agricultural benefits c + 1 755 + 3 063
Project deficit:    
Including capital costs -3 024 - 1 716
Excluding capital costs -1 609 - 301

Source: HTS. Sag e/ Na 'am Evaluation 1976. pg. xv.
a. Medium price, yield, and cost assumptions. valued at ''social'' prices.
b. Excluding costs of vehicles and equipment included in farm costs in the form of a depreciation allowance.
c. Net labour. machinery, and farm input costs. but exclusive of irrigation costs.

The following conclusions can be drawn from the financial analysis.
a) A large current account deficit will occur. The annual subsidy required, on medium assumptions. rises to about S 300.000 for present agricultural practices. and to S 260,000 if intensive agricultural systems are achieved. Capital costs represent. of course. an additional subsidy.
b) The method suggested for charging the farmer is a compromise designed to be practicable and to maintain financial incentives. It would give an annual income of about S 190 with present yields. and S 400 if high yields are achieved. These compare with an annual income of about S 40-50 from rain-fed agriculture. Higher charges could be made, but even so, settlers could not possibly pay for the full farm and irrigation costs.
c) The example illustrated in Table 13 indicates that total current costs (excluding settler labour) could amount to more than six times as much as the income accruing to the settlers. In other words, S 6 or more will be spent (mainly on imported fuel) for every S 1 of settler income created.

These analyses demonstrate that the Sag el Na'am project cannot be justified on economic or financial grounds. It is expensive to construct and operate, and a continuing annual subsidy of about S 260,000300,000 will probably be required from central government funds. The project will benefit only about 3,000 to 3,500 people, and even if the money involved was to be given away, many more people could be assured of a comparable standard of living at less cost to the balance of payments.

TABLE 14. Present Valuea of Costs, Benefits, and Net Return in 1975/76 (in thousands of S)

Present Value Present Value/
Well Command
  (No.) 8% 10% 15% 8%
Capital and Overhead Costs          
Capital costs 40 - 1 415 - 1 346 - 1 218 - 35.4
Overhead costs 40 - 455 - 394 - 290 - 11.4
Agricultural Benefits: Present System          
Summer pulse/winter cereal 20 - 578 - 489 - 338 - 28.9
Summer cereal/winter pulse 15 - 370 -313 - 215 - 24.7
Garden plots - +4 +3 +2  
Total on settler holdings 35 - 944 - 799 - 551 -27.0
Summer forage/winter cereal 2 - 102 - 86 - 60 - 51.0
Perennial forage 2 - 110 - 92 - 60 - 55.0
Horticulture 1 +2 +1 +1 +2.0
Total on project as a whole 40 - 1 154 - 976 - 670 -28.9
Agricultural Benefits: Intensive System          
Summer pulse/winter cereal 20 -9 -8 -5 -0.5
Summer cereal/winter pulse 15 - 3 - 1 +2 -0.2
Garden plots - +256 +217 +151  
Total on settler holdings 35 +244 +208 +148 +7.0
Summer forage/winter cereal 2 -83 - 71 - 49 - 41.5
Perennial forage 2 - 102 - 85 - 56 - 51.0
Horticulture 1 +95 +81 +58 +95.0
Total on project as a whole 40 +154 +133 +101 +3.9
Net Present Value of Project          
Including capital costs:          
Present system 40 - 3 024 - 2 716 - 2 178 - 75.6
Intensive system 40 - 1 716 -1 607 - 1407 - 42.6
Excluding capital costs:          
Present system 40 - 1 609 - 1 370 - 960 - 40.2
Intensive system 40 - 301 - 261 - 1 89 - 7.5

Source: HTS. Sag el Na 'am Evaluation. 1976. p. 177.
a. Based on medium yield. price, and wage assumptions

TABLE 15. Returns for a 5.5 Feddan Settler Holding (fS per holding)


Present (Non-intensive) System

Intensive System



Sorghum/Ful masri

Summer/ Forage Wheat

Perennial Forage

Groundnuts/ Wheat

Sorghum/ Ful masri

Summer Forage/ Wheat

Perennial Forage

Gross Return
Summer crops 240.0 151.0 137.5 275.0 450.0 234.0 200.0 400.0
Winter crops 300.0 375.0 300.0   431.0 600.0 431.0  
Garden crops 123.8 123.8 123.8 123.8 258.8 258.8 258.8 258.8
Total 663.8 649.8 561.3 398.8 1,139.8 1 092.8 889.8 658.8
Farm Costs: Excluding Labour Costs
Summer crops 119.0 48.0 22 5 45.0 155.5 113.0 47.8 95.5
Winter crops 71.0 74.0 71.0   137.5 91.5 137.5  
Garden crops 12.6 12.6 12.6 12.6 72.6 72.6 72.6 72.6
Total 202.6 134.6 106.1 57.6 365.6 277.1 257.9 168.1
Irrigation Costs
Summer crops 442.5 364.5 612.6 916.5 442.5 364.5 612.6 916.5
Winter crops 311.5 296.0 311.5   311.5 296.0 311.5  
Garden crops 99.2 99.2 99.2 99.2 99.2 99.2 99.2 99.2
Total 853.2 759.7 1,023.3 1,015.7 853.2 759.7 1,023.3 1,015.7
Net Return
Summer crops -321.5 -261.5 -497.6 -686.5 -148.0 -243.5- 460.4 -612.0
Winter crops -8.25 + 5.0 - 82.5   -18.0 +212.5 - 18.0  
Garden crops +12.0 +12.0 +12.0 +12.0 +87.0 + 87.0 +87.0 +87.0
Total - 392.0 - 244.5 - 568.1 - 674.5 - 79.0 + 56.0 - 391.4 - 525.0

Source: HTS. Sag el Na 'am Evaluation, 1976. p. 186.

If the project goes ahead, it will be important to ensure that the costs and difficulties of implementation are minimized. Nothing can be done about the great depth from which the water must be pumped, but there are other measures which could be taken to support the project to assure that, if it continues, it is as successful as possible.

3.3.2 Economic Evaluation

Table 14 summarizes the results of the economic evaluation. The life of the project is taken to be twenty years, with Year 0 in 1975/76 and Year 20 in 1996/97. Three alternative interest rates are used to illustrate the sensitivity of the results to changes in the assumed opportunity cost of capital. Eight per cent probably reflects conditions in the Sudan most closely and is used in subsequent sensitivity tests. A number of general conclusions can be drawn:
a) The project as a whole gives a heavy negative return, equivalent to a present value of S 3.0 million at 8 per cent for the present system of agriculture, and S 1.7 million for the intensive system: these are equivalent to an annual average loss of S 118 and S 67 per feddan for the whole area over the life of the project. For the settlement area alone, the-annual losses are equivalent to S 626 and S 337, respectively, for a 5.5 feddan holding. When it is recalled that the annual average income of a family on the Goz amounts to only S 40-50, such losses are clearly exorbitant.
b) If capital costs are excluded (on the grounds that these have already been incurred or are committed), then at 8 per cent the annual losses for the whole area are equivalent to S 62 and S 11 per feddan. In other words, even excluding capital costs, the benefits fail to cover overhead. In the settlement area, the equivalent annual losses are S 325 and S 37 per 5.5 feddan holding.
c) Considerable variations occur in the returns from different rotations. At one extreme. the two-forage rotations show a heavy loss, which is only slightly reduced if intensive practices are adopted. At the other extreme, horticulture (and hence garden plots) is marginal under present conditions but is substantially in surplus under intensive conditions. In between. the main summer pulse/winter cereal and summer cereal/winter pulse rotations show negative returns under existing conditions and are marginal under intensive conditions: these. however. disguise significant seasonal differences. since heavy losses during the summer (especially for summer cereals) are offset by more favourable returns from the winter crops. Although horticultural returns are taken to represent the returns from the garden plots, this may prove optimistic and it is unlikely that more than the present returns will be achieved by settlers.


The Sag el Na'am Irrigation Project shows impressive results of producing agricultural crops under adverse environmental conditions. The price to be paid is a very high pumping cost with an internal rate of return of the project well below zero. This means that the gross returns from the present system fail to cover farm and irrigation costs by a wide margin. Even if higher yields could be achieved.

3.4 Babanusa nomads' settlement project


The project was designed to open opportunities for nomads to settle on 44 potential ranch sites of 10 x 10 km selected in the West Kordofan Babanusa area. It was hoped that the livestock would provide a regular supply of milk for the Babanusa Milk Factory to stabilize market supply on the one hand and additional income for the nomads on the other. The project was to serve as a nucleus for additional agricultural activities and for the provision of central services (schooling. health, etc.).

Production Problems

Southern Kordofan Province is approximately 135,000 km in area. The central part is dominated by the Nuba Mountains and the basement-complex rocks, of which there are four major hill masses and a large number of minor. isolated hills. The mountains are surrounded by pediments and a gently undulating pediplain with soils varying from coarse. gravelly clays to dark grey and black cracking clays. the socalled ''black cotton soils," and alluvial soils. These together make up around 45 per cent of the area, and the uncultivable rocky jebels constitute around 23 per cent.

The western part of the province, Meseriya, is, in terms of the land systems encountered, very similar to the adjacent parts of Southern Darfur. It is made up largely of sand sheet (goz) and dunes, and in the small farm surplus would be insufficient to cover overhead costs. Iet alone to generate returns to offset capital costs. The project has an adverse impact on the Sudan's balance of payments. If local and foreign transactions are weighed to reflect the scarcity of foreign exchange, the economic viability is very negative.

But for pressing political and social reasons, projects of this type seem to have justification as long as suitable alternatives cannot be found. Keeping people in such areas occupied with subsidized employment may justify the high cost to the society as long as the project is used mainly to bridge a time gap until more productive employment can be created in other sectors. the south, fine alluvial deposits derived from the sand and the mountains. A belt of regebas-broad meandering channels and oxhows, lakes and depressions with spinal water courses, where water stands during and for some time after the rains-is found in the extreme southwest corner. The light sandy goz soils, which are excessively well-drained, make up around 32 per cent of the area.

The province lies between the 450 mm and 850mm mean annual isohyets with a rainy season which extends between the end of May and early June. up to the first half of October. The rainfall and the duration of the rainy season increases from north to south. During the recent drought (1968-72) in the Sahel zone, precipitation in the area fell 1020 per cent below the 30-year average (1941-70). However. the incidence of the drought was very variable, with central and eastern Meseriya recording above-average rainfall, while in the Nuba Mountains rainfall was 1 3-14 per cent below average.

The entire area falls into the low-rainfall woodland savanna formation type of natural vegetation. with the major local variations reflecting clay or sand soil types. The region is within the limits in which rain-fed agriculture is feasible.

With 7-8 months of the year without rainfall, perennial sources of water for human and livestock consumption are extremely important. In Meseriya, there are very few naturally occurring perennial water sources, being limited to the stretches of Bahr el Arab below Abyei. Lake Keilak, and possibly some of the larger regebas. Shallow clay basins and some low-yielding. shallow well fields are used to exploit the sub-surface water to be found in the course of Wadi el Ghalla. In the Nuba Mountains, some sub-surface storage from the intermittently flowing streams provides water from pools and. late in the dry season, from shallow, hand-dug depressions (mashush) in the stream beds. Also, in the coarse deposits surrounding the jebels. there are deep wells, often tapping fissures in the basement bedrock.

Undoubtedly, the most important change brought about in the economy and ecology of the province has been effected through the provision of new sources of perennial water supply through the construction of deep tube wells and hafirs. The first tube wells were sunk in 1927-28. but the major expansion came in 1967-72 during the "Anti-Thirst Campaign." During this period the number of wells in the west increased fourfold, with many of them in Meseriya. The bores generally tap the Nubian or Um Ruwaba aquifers or, occasionally, the weathered zone of the basement complex. The bores are often up to 200 meters deep, with diesel pumps supplying water for human beings and livestock through water yards at a charge of S 0.002 per four-gallon tin.

Hafirs are simple artificial reservoirs into which water is channelled and stored. The first machine-excavated reservoirs in Kordofan were brought into use in 1947 in the Nuba Mountains and Tegale. often located on the flood plain of the khors in order to be filled during the rains. Water is provided free for human and livestock consumption. Provision is made for water to be drawn through extraction wells, but in many cases these are not operational and all users, including cattle. must enter the hafir to draw water, so that it is often of very poor quality.

The main reason for the failure of the ranches was the location of ranch blocks on major and minor migration routes of the pastoralists, enclosing considerable areas of existing cultivation and areas over which both sedentary and migratory populations recognized rights. All parties concerned strongly asserted their rights to cultivate and graze, and cultivation inside the ranches increased rapidly, defended by strong thorn fences. In addition. the carrying capacity of the range in the area was too low to support the proposed number of livestock on year-round occupancy, and the production of meat and milk would not have been sufficient even to cover costs of operation.

Livestock marketing is either controlled by rural councils, where sales are registered and taxed by clerks. or handled by a large number of smaller markets operated by individuals, often merchants who buy the right to collect sales taxes. A complex system of merchants, agents, traders. intermediaries, and tribal guarantors, held together by close financial and personal relationships, perform the purchase movement. and sale of livestock. Marketing is highly seasonal, determined by the periods when livestock is in areas accessible to merchants and when movement is possible. All cattle and the majority of the sheep are trekked to the main consumer markets and the Gezira area, or to the export quarantine in Khartoum North. During the dry season, trekking involves heavy mortalities and weight losses, especially in livestock coming from the western areas. The capacity for moving stock by rail is very limited and the service unreliable.

The imperfections in the marketing system, including the often permissive link between marketing and private credit, are difficult to remove. However, if farmers are to respond to the opportunities for increased productivity and to invest in agriculture, they must receive a larger share of the final market value of their produce (for instance, through central purchasing of livestock and institutional credit).

The only reliable estimates of livestock population have been made by the aerial Pilot Livestock Census carried out in Southern Kordofan in 1975:

(in millions) cattle 1.97 goats 0.51
sheep 1.07 camels 0.08

Heavy concentrations of cattle were observed particularly in the alluvial Bahr el Arab dry season areas, well field sites, and around the alluvial valleys in the eastern parts of the Nuba Mountains. Cattle were primarily the indigenous Baggara (beef type), but in the eastern parts they were the Kenana (milk breed). In the Nuba Mountains there are still the small Nuba cattle which are resistant to trypanosomiasis.

The traditional pastoral economy of the province is managed on both sedentary and migratory systems. The Nuba and settled elements in the Baggara tribes manage their herds in the context of settled agriculture, involving the stock in only short distance migrations. Only a small part of the household labour is committed to herding and movement of stock. The true migratory pastoralists move southwards to perennial water supplies and pasture during the dry season and retreat northwards to the rainy season pastures, avoiding the mud and biting flies. The productivity of livestock is very low, particularly amongst the sedentary herds. Average commercial takeoff rates are on the order of 5 per cent for cattle and 15 per cent for sheep. The main reason for the low productivity is the very low level of nutrition, with animals receiving at or below maintenance feed requirements for up to eight months of the year. The main reason for this in turn has been the expansion of livestock numbers beyond the sustained carrying capacity of the range, which itself is shrinking as a result of over-grazing and expansion of cultivation.

The Veterinary Department tries to control diseases, especially rinderpest, C.B.B.P., anthrax, blackquarter, and H.S.C. There are veterinary hospitals, dispensaries, mobile clinics, and doctors in the area. There the efforts are entirely focused on animal health and, in particular, on seasonal vaccination campaigns. The result has been an explosion in the number of animals. However, many nomads still hesitate to have their animals vaccinated if there is not an acute danger. Vaccinations against rinderpest are free of charge, while all others have to be paid for. The fees are collected indirectly through the tax payment per head of livestock. The per-head basis of this tax payment hinders any effective extension service, as the livestock owner is not willing to reveal the number of cattle he owns, nor to discuss their performance.


The project did not reach its objectives. The settling of nomads and supplying of milk to the factory ceased. and from 1975 the programme has been reduced to essentially service provision on just four ranch areas. Apparently the areas for the project were not selected carefully enough so as not to conflict with other tribes demanding traditional rights of grazing and cultivation during the rainy season.

Major shortcomings are reported to be: low intensity of communication between management and field staff, lack of transport, insufficient finances, and absence of co-ordination between different governmental departments. Local people were not involved sufficiently in planning and implementation to accumulate enough interest. The staff showed the usual problems-shortage of qualified cadre, quick transfer. lack of adequate housing, etc. The entire exercise underlines the potential areas of conflict between cultivators and pastoralists and the difficulties of consultation between the local population and the administration in remote areas.


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