Page 82 - Module_5_en

Module
5 CASE STUDY

Saudi Arabia’s food self sufficiency policy
and impact on water resources

9-12 December, 2013 Source: http://www.fao.org/documents/show_cdr.asp?url_file=/docrep/W4356E/w4356e0q.

htm

Environmental issue of concern
Water withdrawal

In 1992, total water withdrawal was estimated at 17 km3, of which 90 per cent was for
agricultural purposes. That was up nearly five per cent over the 16.3 km3 recorded in 1990.
Desalinated water is used for municipal not agricultural purposes because it is too saline for
irrigation even after treatment. Treated wastewater is used to irrigate non-edible crops, for
landscape irrigation and for industrial cooling. However, most of the water used (> 13.5 km3)

comes from non-renewable, deep aquifers. At the 1990 rate of abstraction, it is estimated
that the usable reserves will last for no more than 25–30 years. The quality of the abstracted
water is likely to deteriorate with time because of the flow of low quality water in a given
aquifer towards the core of the depression at the point of use. In 1988, there were 4 667
multi-purpose government wells, and 44 080 multipurpose private wells.

Irrigation and drainage development

The most recent soil surveys (1989) and classifications put the area of land suitable for
irrigated agriculture at about 10 million ha. However, the limiting factor is water. Depletion of
non-renewable “fossil” water already is taking place at a very high rate.

All agriculture is irrigated, and in 1992 the area under water managment was estimated at
about 1.6 million ha, all equipped for full/partial control irrigation. Surface irrigation is practiced
on the old agricultural lands, cultivated since before 1975, which represent about 34 per cent
of the irrigated area. Sprinkler irrigation is practiced on about 64 per cent of the irrigated
areas. The central pivot sprinkler system covers practically all the lands cropped with cereals.

Normally, pumped groundwater from one deep well supplies one or two central pivots. The
irrigation application efficiency of this method is estimated at between 70 and 85 per cent.
Vegetables and fruit trees in general are irrigated by drip and bubbler methods respectively.

80 Integrated Analysis of Environmental Trends and Policies