Agricultural Use

Irrigated agriculture is the major water consumer in Angola (60 % of total consumption) and Namibia (40 %).

The two major factors affecting the future of water use and demand are human consumption and irrigation. The irrigation water demand will be influenced by:

• Progress in water efficiency;
• National legislation on water pricing and rights; and
• Market forces arising from greater economic integration between SADC countries.
   

Angola

In 2004 agriculture was the main economic activity for 71 % of the Angolan population. Agriculture is also the main water consumer. In 2005, of the 2 851 million m³ of water consumed, 90 % were used for irrigated agriculture and 3 % for livestock.

Smallscale irrigation in the Middle Kunene basin.

Source: AHT GROUP AG 2009

( click to enlarge )

Recent data regarding irrigation in Angola estimates that about 340 000 hectares are currently under full or partial irrigation and that the irrigated area in the Kunene basin was about 42 000 ha (representing 12.3 % of total irrigated area in Angola) (SWECO Grøner 2005). According to FAO estimates from 2005 (FAO 2005a), the total potential irrigable area is around 3.7 million ha. Before independence the total area under irrigation was estimated at 400 000 ha (11 % of the potential area). The rehabilitation and extension of irrigated areas has been made a priority activity in rebuilding the country and to ensure food security.

The Kunene River basin is the only basin in Angola currently with a coordinated irrigation plan. Current plans for the basin foresee a considerable increase of an additional 572 000 ha coming under irrigation until 2025. In the short to medium term this will include:

• The rehabilitation of almost 9 000 ha in the Middle and Upper Kunene (6 000 ha near Matala, 2 000 ha by Chibia and 870 ha in Humpata):
• The installation of a further 2 000 ha in the Middle Kunene in the west of the basin (300 ha near Chicungo, 200 ha near Quipungo and 1 500 ha near Sendi).
• The installation of 8 500 ha in the Middle Kunene in the centre of the basin (1 500 ha along the Mucope tributary and 7 000 ha between Calueque and Xangongo).

The water use for irrigation in the Kunene River basin was 372 million m³ (13 % of total irrigation water demand in Angola) in 2005. Thus, an average of 8 900 m³/yr has been applied per hectare of irrigation area.

The water demand for livestock within the Kunene basin was estimated to be 30 million m³ in 2005. This was equal to 29 % of the total water consumption by livestock in Angola (SWECO Grøner 2005).

Cattle farm in the basin.

Source: Tump 2007

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Namibia

Irrigation of crop land consumed about 135 million m³ (40 % of total demand) in 2008. Water Consumption of livestock is estimated in the range of 87 million m³ per year and thus represents the second largest use sector (26 %) in the country.

Agriculture contributed 5 to 6 % of Namibia's GDP for the past five years. However, about 70 % of the Namibian population depends on agricultural activities for livelihood, mostly in the subsistence sector. Animal products, live animals, and crop exports constitute roughly 5 % of total Namibian exports.

Subsistence farming is confined to the "communal lands" of the country's populous north, where roaming cattle herds are prevalent and the main crops are millet, sorghum, corn, and peanuts.

Livestock

The latest available stock census (2006) in Namibia calculated the approximate stock numbers for the main stock categories as follows: 2.4 million cattle, 2.7 million sheep and 2.1 million goats. The total water demand for livestock was estimated to be 87 million m³ in 2008. This includes a wastage of about 50 % due to overflowing reservoirs, evaporation, leaking pipes et.

The livestock water demand within the Kunene water basin was estimated to be about 7.3 million m³ in 2008 (IWRM Plan Joint Venture Namibia 2010). The major stock categories were cattle and goats.

Cattle farming in Lower Kunene basin, Namibia.

Source: Meat Corporation of Namibia 2008

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Irrigation

In 2008, about 9 800 ha were equipped for irrigation: 4 500 ha surface irrigation, 3 300 ha sprinkler irrigation and 2 000 ha flood irrigation (FAO 2010a). The main irrigated areas are:

• The Etunda Scheme on the Kunene River with 640 ha equipped area - surface irrigation (day) and center pivot irrigation (night);
• The Hardap Scheme, supplied from the Hardap Dam. Equipped area is about 2,260 ha - mainly surface and sprinkler, some farmers are changing to drip;
• Schemes along the Orange River (such as Noordoewer Scheme - mainly flood irrigation, Aussenkehr Scheme). Equipped area is about 2,000 ha;
• Schemes along the Okavango River (such as Shadikongoro Scheme - center pivot) with about 1,350 ha equipped area;
• Schemes on the Zambezi River, like the Katima Farm (approximately 200 ha) and the Isisi Scheme (36 ha, flood irrigation).

Further information can also be obtained from the Irrigation Infrastructure chapter.

Studies have been undertaken to determine the broad availability of irrigable soils that could be used to improve food production in Namibia. It was found that only about 950 000 hectares (ha) are highly suitable for irrigation and about 2 650 000 ha are suitable for irrigation. About 10 000 ha are presently under irrigation. If all the highly suitable soils would be irrigated at an application of 15 000 m³/ha/yr the water requirement would be about 14 km³. This is three times more than the total mean annual runoff in the Kunene River or about 1.5 times the flow in the Orange River.