Surface water quality
Data on surface water quality are both scarce and old. Those that exist are mainly on the White and Blue Nile.[1] Water characteristics are subject to the source and types of soil the water runs through.[2] Water pollution comes from agricultural residues and the sugar industry, although the self-purifying capacity of the natural systems is high.[3],[4] Furthermore, the 1975 Public Health Law forbids ‘the disposal of any untreated, treated or partially treated water in natural water bodies’.[5]
Groundwater quality
Groundwater is of good quality and needs little or no treatment. Other factors to be considered in the demand for groundwater are the availability of other sources as well as sociological conditions and political priorities.[6] Results from chemical and bacteriological analysis of samples from a large number of boreholes in many different towns show gross total and faecal coliform bacteria and/or nitrate pollution.[7]
Environmental and health risks
Drinking water and sanitation facilities are rudimentary, especially in rural areas. Piped water is available to only a small portion of the population. Fetching water in some villages is a woman’s job, sometimes involving walking long distances. Riverside towns and villages take untreated water from permanent water sources, which is distributed by donkey carts. During the rainy season, the high load of silt and coliform bacteria is a problem. Somewhat better quality water is distributed by carts and venders when tube wells and/or boreholes are the source.
As in many other African countries, most of the water distribution networks were established before independence.[8] Lead pipes have decayed and newer pipes are made of asbestos, which is also deteriorating. Water is delivered in the cavities where the pipes once existed. The affluent and effluent waters are mixed underground. Further, the pressure is low and water cannot be delivered without the use of booster pumps, which draws the mixed-up waters. In wealthy neighbourhoods, water filters and storage tanks are widely used. The tanks and ‘desert-type’ water coolers provide excellent breeding grounds for mosquitos. As a result, malaria has become endemic all year around. In addition, new residential neighbourhoods get flooded by rainwater due to poor drainage and almost non-existent storm drains. This standing water is another excellent environment for water-related diseases. The widespread use of septic tanks and soak-away wells contaminate the groundwater aquifers.[9] Groundwater is increasingly being used to augment drinking water.
[1] Talling, J.F., 1957. ‘The Longitudinal Succession of Water Characteristics in the White Nile.’ Hydrobiologia, 11 (1): 73-89.
[2] Bishai, H.M., 1962. ‘The Water Characteristics of the Nile in the Sudan with a Note on the Effect of Eichhornia crassipes on the Hydrobiology of the Nile.’ Hydrobiologia, 21(4): 357-382.
[3] Hammerton, D., 1972. ‘The Nile River. A Case Study.’ Symposium of River Ecology and Man. Academic Press.
[4] Moghraby, A.I. el-, 1972. A Study of the Zooplankton of the Blue Nile. PhD thesis, University of Khartoum.
[5] Moghraby, A.I. el-, 1993. ‘Water Resources Management in the Sudan. A Case History of Disaster.’ Proceedings of UN Workshop on Disaster Management, Khartoum, May 1993.
[6] Elkrail, A.; Hamid, A.; Obied, B., 2012. ‘Hydrochemistry of Groundwater at Omdurman Area, Khartoum State.’ International Journal of Civil and Structural Engineering, 2 (4): 1051-1059.
[7] SNCIHP, 2000. Vulnerability of Groundwater Resources of Sudan to Pollution Risks. Technical report, Sudan National Committee for IHP, Khartoum, Sudan.
[8] Odada, E., 2009. Overview of Africa Water Challenges and Opportunities. IAP Workshop, March 2009, Pretoria, South Africa.
[9] Abdel Rahim, M.A., 2000. ‘Pollution in the Water Supply Wells of Khartoum.’ Bulletin of Engineering Geology and the Environment, 58(4): 257-264.