FAO REPORT ON LIBYA | |
GEOGRAPHY, POPULATION AND WATER RESOURCES | |
The Libyan Arab Jamahiriya, situated on the northwest Mediterranean coast of Africa, has a total area of about 1.76 million km2. The cultivable area is estimated at 2 170 000 ha, which is 1.2% of the total area.
TABLE 1
Basic statistics and population
Area of the country Cultivable land Cultivated land |
1993 1992 1987 |
175 954 000 2 170 000 1 933 648 |
ha ha ha |
Total population Population density Rural population |
1994 1994 1990 |
5 225 000 3 18 |
inhab. inhab./km2 % |
Water supply coverage Urban population Rural population |
1990 1990 |
100 80 |
% % |
The total population is about 5.2 million inhabitants (1994). The population density is 3 inhabitants/km2 and the rural population was estimated to be only 18% in 1990. Agriculture contributes less than 5% to GDP, although it provides employment for approximately 13% of the active population.
Climate and water resources
The average annual rainfall is 26 mm. It is more than 100 mm/year over only 7% of the land surface. The highest rainfall occurs in the northern Tripoli region (Jabal Nafusah and Jifarah Plain) and in the northern Binghazi region (Jabal al Akhdar): these two areas being the only ones where the average yearly rainfall exceeds the minimum value (250-300 mm) which is considered necessary to sustain rainfed agriculture. Rainfall occurs during the winter months and shows an extreme variability from year to year and from place to place.
The total mean annual runoff water calculated or measured at the entrance of the wadis in the plains is estimated at 200 million m3/year, but part of it either evaporates or contributes to recharge of aquifers. Therefore the surface water resources are roughly estimated at 100 million m3/year. Sixteen dams, with a total storage capacity of 387 million m3 and with an expected average annual volume of water controlled in the order of 60 million m3, had been constructed by 1991. Additional dams are planned, to achieve a total storage capacity of 686 million m3. This disproportion between the average annual runoff and the storage capacity of the dams is made with the purpose of storing the runoff water of exceptionally wet years.
TABLE 2
Water balance
Water resources: Average precipitation Internal renewable water resources total Internal renewable water resources per caput Global renewable water resources Dependency ratio Total dam capacity De-salinated water |
1994 1992 1988 |
26 46.1 0.6 115 0.6 0 0.4 70 |
mm/yr km3/yr km3/yr m3/yr km3/y % km3 106 m3/yr |
Water withdrawal: - Agricultural - Domestic - Industrial Total per caput as % of internal renewable water resources Other withdrawal |
1994 1994 1994 1994 |
4 000 500 100 4 600 880 767 - |
106 m3/yr 106 m3/yr 106 m3/yr 106 m3/yr m3/yr % 106 m3/yr |
Wastewater: Produced Treated Re-used treated wastewater |
1990 1990 |
- 100 100 |
106 m3/yr 106 m3/yr 106 m3/yr |
TABLE 3
Irrigation and drainage
Irrigation potential |
1992 |
750 000 |
ha |
Irrigation: 1. Full or partial control irrigation: equipped area - surface irrigation - sprinkler irrigation - micro-irrigation % of area irrigated from groundwater % of area irrigated from surface water part of the equipped area actually irrigated 2. Spate irrigation area 3. Equipped wetland and inland valley bottoms 4. Other cultivated wetland and inland valley bottoms 5. Flood recession cropping area Total water managed area (1+2+3+4+5) as % of cultivated area increase over last 10 years power irrigated area as % of water managed area |
1990 1990 1990 1990 |
470 000 - 470 000 - - - 51 - - - - 470 000 - - - |
ha ha ha ha % % % ha ha ha ha ha % % % |
Full or partial control schemes: Criteria Large schemes > - ha Medium schemes Small schemes < - ha Total number of households in irrigation |
- - - - |
ha ha ha | |
Irrigated Crops: Total irrigated grain production as % of total grain production Harvested crops under irrigation - |
- - - - |
t % ha ha | |
Drainage - Environment: Drained area as % of cultivated area Flood-protected area Area salinized by irrigation |
- - - - |
ha % ha ha |
Water withdrawal (total: 4.6 km3 in 1994)
Currently, recharge of aquifers occurs only in the northern regions, namely in the northwestern zone, Jabal Nafusah and Jifarah Plain, and in the northeastern zone, Jabal al Akhdar. Renewable groundwater resources are estimated at 0.8 to 1 km3/year, but part of it (perhaps 50%) now flows out either to the sea or to evaporative areas (sabkhas) and could not be abstracted without affecting the environment, because of the deterioration of water quality by saline water encroachment. South of the 29th parallel, an important development of Palaeozoic and Mesozoic continental sandstones enabled water to be stored safely during the long period of the late Quaternary, when the climate turned extremely arid. The major part of water used in Libya will be coming from these huge fossil reserves.
Total water withdrawal for agricultural, domestic and industrial purposes was estimated at 4.6 km3 in 1994 (Figure 1).
A number of de-salination plants of different sizes have been built near large municipal centres and industrial complexes. The total capacity of installed plants is approximately 140 million m3/year, but parts of them are either not in use or only partly operational. It is estimated that only 70 million m3/year is annually de-salinated.
A number of sewage treatment plants are already in operation or planned for the near future. When all the plants become operational, their total output will average 285 000 m3/day or about 100 million m3/year. All treated water is currently used for irrigation.
IRRIGATION DEVELOPMENT
The total water managed area is approximately 470 000 ha, most of it for sprinkler irrigation because of the sandy soils prevailing in most areas of Libya. Of these 470 000 ha equipped for full or partial control irrigation, according to figures from several years ago, only 240 000 ha was actually irrigated, distributed as listed in Table 4.
There are three different categories of farming in the irrigation sub-sector:
TABLE 4
Regional distribution of irrigation
Zone |
Area actually irrigated (ha) |
Water use (106 m3/yr)* |
Year (approx.) |
Murzuq Basin Jabal Nafusah; Suf al Jin; Western Sirte; Hammada el Hamra Jifarah Plain Al Jabal al Akhdar Al Kufrah-As Sarir |
50 000 25 000 100 000 40 000 25 000 |
551 241 500 150 423 |
1985 1985 1985 1985 1990 |
Total |
240 000 |
1 865 |
* Figures probably under-estimated.
smallholders, generally on 1 to 5 ha plots, receive substantial State support for water equipment, energy, and agricultural inputs; this type of farming represents approximately 30 to 40% of the total irrigated area but is mostly concentrated in the traditional development areas, i.e., the Jifarah Plain, the Jabal al Akhdar, and the Murzuq Basin;
large-scale state farming, mainly located in the southern areas, where new irrigation schemes have been set up based on highly productive deep wells supplying water to blocks divided into small plots and cultivated by small-scale farmers; and
large-scale state farming, mainly located in the desert areas (usually pivot systems), operated by state technicians and workers.
At present, no water fees are imposed on water users.
INSTITUTIONAL ENVIRONMENT
Responsibility for all water resources assessment and monitoring rests with the General Water Authority, while the Secretariat of Agriculture and Animal Wealth is responsible for the development of irrigated agriculture and the implementation of major projects. A special Authority The Great Manmade River Water Utilization Authority is responsible for the use for agricultural purposes of the water transported from the desert to the coast. The Secretariat of Municipalities takes care of water supply to urban settlements.
TRENDS IN WATER RESOURCES MANAGEMENT
Irrigation development in Libya is linked to the implementation of the water transport project from the desert. The Great Manmade River Project consists of the following five phases:
Phase 1: 2.0 million m3/day of water will be conveyed to the coastal area, extending from Binghazi to Sirt. Water will be produced by two well fields, Sarir and Tazirbu;
Phase 2: 2.5 million m3/day of water will be conveyed to the Jifarah Plain in northwest Libya from more than 500 wells distributed in several well fields located in the northern and northeastern part of the Murzuq basin;
Phase 3: 1.6 million m3/day of water will be added to Phase 1 from an additional well field within the Kufra basin;
Phases 4 and 5: These phases will not involve any additional water production. Instead, conveyance lines of Phase 1 will be extended farther to the east to reach Tobruk, and farther to the west to link with Phase 2 pipelines.
Part of the water transported will be used for the water supply of the major cities of the coast: Tripoli, Binghazi, Sirt and Misratah.
MAIN SOURCES OF INFORMATION
Pallas, P. 1980. Water resources of the Socialist People's Libyan Arab Jamahiriya. In: The Geology of Libya. Proceedings of the Second Symposium on the Geology of Libya. London: Academic Press.
Salem, O.M. 1992. The Great Manmade River project. Water Resources Development, 8(4).