Dialog about water resources and sustainable development in the south east Tunisian region between Gabes University students and the south east production manager for Kamel Fethi  :

Question n°1

Tunisia is located in a dust bowl, are water resources sufficient enough to ensure sustainable development?

Answer n°1

Tunisia has indeed finite water resources. Her water potential is approximately equal to 5 billions m 3 per annum. The resources that can be mobilized per capita annually account for 465 m 3 and this is deemed by far lower than the poverty line set out by the United Nations Operations - 1000 m 3-. However, Tunisia has proved successful with regard to her resource mobilization policy thanks to a well developed and properly executed integrated management strategy. This strategy that helped mobilize more than 90 % of resources that could have been mobilized in 2006 is also based on the management of water demand through the establishment of water conservation culture and the development of non conventional resources particularly in the southern Tunisian region.

Question n°2

How do non conventional resources contribute to water resource mobilization?

Answer n°2

Most good quality water resources (salinity lower than 1.5 g/l) are already in use. Given that the brackish resource potential that can be found in the southern Tunisian region is substantial, there is need to start improving water quality by resorting to desalination techniques

Question n°3

What is Tunisia desalination production capacity?

Answer n°3

Tunisia desalinated water production capacity amounts to approximately 110, 000 m 3/day produced by about 70 units; 57% of which is devoted to drinking water. Four desalination treatment plants run the production through the SONEDE: Kerkennah ( 3,300 m 3/day, Gabès: 30,000 m 3/day, Djerba: 15,000 m 3/day and Zarzis: 15,000 m 3/day). These plants use the reverse osmosis technique.

Question n°4

Why was the reverse osmosis employed?

Answer n°4

This technique that consists in separating salts from water by means of a semi-permeable membrane under a gradient of pressure was selected following a research and economic report that showed reverse osmosis was the most appropriate approach considering its high level of automation and implementation simplicity. Over the past years, this technique has undergone major developments.

Question n°5

What is the future of water desalination in Tunisia?

Answer n°5

In order to avoid overexploitation of groundwater as per the requirements of sustainable development, sea water desalination will be playing a major role in the future. The Tunisian authorities have previously called for tenders to build for the first time at Djerba a sea water treatment plant with a capacity of 5,000 m3 /day. This plant will be build before 2010 summertime as part of a concession. The Tunisian authorities have also planned to build at Mareth another sea water desalination treatment plant of the same capacity to strengthen water resources of drinking water supply systems located at the south east Tunisian region.