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1.2Water resources management

1.2.1 Institutional aspects

In Tunisia, the legal instrument for water management is the Waters Code promulgated in 1975 (Law 75-16 of March 31, 1975).

The Ministry of Agriculture, Environment and water resources has large assignments of the Water Code administration. It is commissioned to resources scheduling and development, and public water production by the system of dams or deep wells, and determination of water allowances to different sectors of water use. The struggle of pollution and the treatment of wastewaters depends on the National office of purification (ONAS) reattached to this Ministry.

While assuring a centralized management of dam-reservoirs, the Ministry of agriculture, environment and water resources adopted since 1989 an extensively decentralized organization. To the level of each of the 24 regional department, a Regional Administration of Agricultural Development (CRDA),

CRDA public establishment with administrative character with financial autonomy, is charged to the application of the Ministry politicizes.

The public establishments with industrial and commercial character involved in the water are following:

- The National society of exploitation and Distribution of Waters (SONEDE), public organism depending on the Ministry of agriculture, environment and water resources and charged of the exploitation and the distribution of the drinking water in cities and villages of 2.500 inhabitants.

- The Society of exploitation of the Channel and the network of the North Waters (SECADENORD), depending on the Ministry of agriculture, environment and water resources and responsible of the management of the transfer of water adduction in view to supply SONEDE and some CRDA from the North basins.

- Groupings of Collective interest (GIC) are associations of owners and users, endowed of the civil responsibility and the financial autonomy and charged of the exploitation and the upkeep of irrigation and drinking systems of water realized by the government. Currently, 2500 functional GIC’s of which 1600 groupings to supply drinking water to 1,4 million of rural inhabitants (40% of the total rural population), and 900 groupings of irrigation covering 116000 hectares, either 58 % of the public irrigated areas.

- The private sector is essentially implied in the underground water management unless 50 m of depth. These resources are freely exploited from well equipped by pumping material. The almost totality of waters thus mobilized is destined to the irrigation of privet irrigated areas. Currently they are about 177.000 hectares (47% of the total irrigated area of the country).

1.2.2 Economic aspects

In view to encourage the private investment in water use domains, the law of 1993 foresees measures of incitement and encouragement:

- The exoneration of taxes on the import of many hydraulic facilities for irrigation.

- Credits and subsidies to relative investment expenses to the realization of private projects, and to the utilization of saving water techniques in irrigation.

In the sector of the drinking water in management by the SONEDE, the level of water losses is appraised to 19%. For saving water, a tariff policy founded on the adjustment of tariffs to the national ladder and the progressivity of tariffs, wich penalizes the high consumptions and discourages wasting. In fact, a « social » tariff for the weak consumptions is maintained. Tariffs of the urban drinking water cover currently 95% of the total costs. The mobilization of resources from dams remains of the responsibility of the Government.

Compared to the urban cities, supplying fresh water to the rural zone doesn't benefit on any fixed tariffs. Every GIC is in the obligation to adopt the specific tariffs covering charges of them exploitation. Nevertheless, a subsidy is often granted by the Government in charge by the CRDA’s for facilities replacement.

In irrigation sector, water rental charges are generalized on the total public irrigated areas in direct management by the CRDA’s (83000 hectares) or by the GIC’s (116.000 hectares). The adopted tariffs are very variable and depend notably on the regional context, of the level of intensification and cultures exercised in the irrigated areas, with in some cases of the preferential tariffs for cultures to strategic character (cereals and fodders) or for the reuse of treated wastewater in agricultural. The rate of exploitation and upkeep charges recovery in the irrigated areas varies from 50 to 100%. A yearly increase of 15% of tariffs has been decided since 1990 in view to accelerate the total recovery of costs of water exploitation, and to encourage to a prudent management of the agricultural exploitations and to a faster adoption of processes and techniques of water saving.

1.2.3 Water supply facilities

Historically, Tunisia has an important tradition in the mobilization and management of waters, as testify vestiges existents: the Roman aqueducts, the feskia in Kairouan (Center). The system of water sharing in the South and the system of water capture in Gafsa.

The country has been endowed of a varied infrastructure, some of them are interconnected (Figure.6): 22 big dams, 680 hillside stream dams and hillside lakes, 2830 drills (deep wells) and 120000 wells permitting to assume the different demands of drinking water and the various sectors: agricultural, tourist, industrial and environmental.

  • Conventional water development options:

- Supply management

The mobilization of conventional resources and integrate the underground resource management with a regional basis with good mobilization of the deep underground resources and more intensive aquifer recharge, while using the results of the experimental program of artificial recharge.

    • Management of water resources

To provide to the increasing water demand, a strategy of conventional water resource mobilization has been adopted since 1990 in view to mobilize, on the horizon 2005, 90% of surface resources and 100% of the underground resources. Otherwise, it is considered to reinforce and to spread connection between reservoirs and the regional transfers.

    • Quality Control

The high saltiness level of the majority of water in Tunisia reduces possibilities and limits irrigation use. Fast urban and industrial extension zone develop biologic and chemical pollutants. During the last years, to control the corresponding risks, it has been introduced many programs of mobilization with measure networks and observation to follow the quality of all resources of water (surface and underground), as well as the evolution of the soil saltiness in the irrigated areas.

- Collection of rainy waters
In Tunisia the rainy water collection with basin constitutes a millennial traditional practice. It is developed to provide drinking water needs of dispersed populations. The individual basin construction is encouraged by government credits. During the last years, more than 10.000 units are realized at the center and south of the country.
- Enforcing water authorities’ regulations
During the last twenty years, the recruitment and training privileged the domains of the exploitation of water systems construction. However, by reason of the evolution of needs of the Ministry of the agriculture, many specialized programs of engineers’ formation have been realised. They concern computer technologies, information systems of management, communal involvement related on saving water.
- Research and development
Although acquirements of water domain research are numerous, notably the reuse of marginal water in agriculture, research is considered even insufficient. A new reform of the institutional agricultural research has been hired from 1996. This action will be able to avoid the disparity of the research actions and to spread the activity to other strategic domains: saving water, management optimisation, economic and social aspects of the water use and valorisation of marginal water.

1.2.4 Non-conventional water development options:

    • Reuse of Treated Wastewater

The exploitation of no-conventional water resources (the reuse of treated wastewater) is one of ways of the national strategy to mobilize water resources. Even though these waters count only about 5% of the available resources, they present the advantage of the stability during the year compared to the various rainfalls without considering that their mobilization avoids environmental impacts.

Since 25 years, the purification sector knew a continuous development that permitted the setting up of importing infrastructure Park. At 2001, 61 treatment plants were operating and produced 156 millions of m3 of treated wastewater. The park of these purification unit is evolving to reach 135 treatment plants in 2006 producing more than 200 millions of m3 of treated wastewater and will adjoin 250 millions of m3 in 2010.

The treated wastewater volume is function of several parameters of which the most important as following:

  • The volume of drinking water consumed by the different users.

  • The rate of discharge that is function of user type

  • The rate of connecting to the purification networks.

  • Rainfall qualities intercepted in purification networks.

  • The capacity of the park of purification units

The following table 5. gives quantities of treated wastewater in Tunisia during the period 1996-2000 (in millions of m3).

Table 5.






Treated wastewater (M m3/year)






Rate of growth (%)





Number of treatment plant






(Source: ONAS)

In 2000, the volume of treated wastewater reused is 27,437 millions of m3 in the agricultural and other sectors: golf course, green spaces. In 1999, this volume was 19,148 millions of m3.

Urban and periurban of the Capital totalize a reuse volume of treated wastewater of 8,841 millions of m3 in 2000, either about 32.2% of total quantities reused in the country. The rate of reuse is about 11.5%.

    • Desalination:

The brackish water desalination took the extension to improve the quality of the intended drinking water to some tourist urban area and complex agglomerations of the south region. The total capacity installed by SONEDE is 20.000 m3/day, which increased in 2000 to 58.000 m3/day following the extension of the Gabes station and the operating of Jerba-Zarzis station. In the industrial and tourist domain, the total capacity of desalination units reaches 30.000 m3/day.

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