The year 1992 was a tipping point in Tunisia's water resource management and strategy. The drought that troubled the entire region that year forced Tunisia to recognize that a sound water management policy must be developed to deal with droughts and water shortages. The urgency of the matter led the government to focus its attention on the building of large water infrastructure to the disadvantage of the traditional systems developed over centuries of rural practices.
Although 1992 was a pivotal year, water shortages became the topic of a debate that lasted throughout much of the 1980s. The debate was sparked as a result of consecutive periods of drought. In 1992 a real strategy was put forward to mobilize water resources in a plan that had to be thoroughly reviewed every five years. Tunisia's new policy was based on a three objectives: the mobilization of conventional resources (i.e. surface water), underground resources located at least 50 meters deep, and non-conventional resources such as the treatment of used and waster water. The country boasts modern dam irrigation in the central regions but also uses old rainwater harvesting techniques in the Sahara.
Despite a semi-arid climate in the north and an arid one in the south, Tunisia's investment in water infrastructure began to pay off with the volume of water collected in 2000 exceeding 4.8 billion cubic meters of surface water, compared with 3.1 billion in 1970. The volume of underground water collected in 2000 was 700 million cubic meters, while the volume of deep underground water was 1.4 billion cubic meters.
While these results are encouraging, Tunisia's water consumption is expected to grow further, largely as a result of improvements in the population's standard of living and the expansion of agriculture. Today, farming consumes 84% of the total used water, while household water consumption accounts to just 12%. Could Tunisia face a major water shortage then? From the infrastructure standpoint, Tunisia is well prepared as its dams and reservoirs across the northern and central regions are interconnected, allowing a more equal distribution of water nationwide. This system is designed to absorb water during humid period, providing farmers and livestock owners with sufficient water. The system also captures and stores water during rainy periods to regenerate the underground reserves in the south, while reducing risks of floods in the center of the country.
The sector is centrally managed and by 2011 the government's tenth plan envisages a 95% use of the dam and reservoir system capacity. Tunisian planners believe their goal could be reached thanks to the country's 23 major dams and hundreds of accompanying infrastructure units such as over 2,000 drillings and 36 projects to replenish deep underground reserves. But there are risks given the nature of water, and agriculture is being singled out as a potential trouble spot. Agriculture consumes large volumes of water, amounting to about 4,500 m3 per hectare of irrigated land per year with dam wate,r and 6,000 m3 per hectare per year of water originating from surface wells. However, agriculture in Tunisia also uses treated wastewater at the economical rate of 4,000 m3 per hectare per year. As such, the use of recycled wastewater is expected to be favored so as to save some 5% of the normal water in the 2030 horizon. Tunisia is hoping to irrigate some 100,000 hectares of land in 25 years using treated wastewater.
© The North Africa Journal 2005
