North Western Sahara Aquifer System - SASS

Approval Date

Approved by le Fonds Français pour l’Environnement Mondial (FFEM) and the Global Environment Facility (GEF) in 2008

Project Duration

Phase III: 5 years (2010 – 2015)

Financial & Technical Partners

Le Fonds Français pour l’Environnement Mondial (FFEM) and the Global Environment Facility (GEF)


Country of operations

Algeria - Libya – Tunisia

Main Beneficiaries

Algeria - Libya – Tunisia


The « North Western Aquifer System » is shared by Algeria, Libya and Tunisia. It extends over one million km2 and contains considerable yet little renewable water resources. With the aim of establishing sustainable development in the region, OSS has conducted between 2000-2010 a number of studies as part of two major projects (SASS I and SASS II). These studies led to a better knowledge of the NWSAS, the establishment of a common information system and the instauration of a permanent Consultation Mechanism between the three partner countries. In addition, the studies showed that the current form of agricultural development based on offer leads to many risks related to high water mobilization costs, soil salinization, and degradation of water quality. The studies have brought insight into the inefficiency of the traditional irrigation techniques used and the lack of water valuation. This situation could be affected in the future due to the constant increase of water needs and the adverse impacts of climate change. It is within this framework that the SASS III project was launched with the aim of producing operational recommendations for establishing a sustainable agriculture and preserving water and soil resources.

Project Status


Achievements & Results


  • Socio-economic components

The socio-economic component aims essentially to study the behaviour of the main user of the NWSAS resource, namely the irrigator, with a view to assessing his real valuation of water and especially his adaptation methods to water scarcity and degradation. In addition, based on the data collected through surveys, an integrated hydro-economic model which explicitly takes into account all the variables and determinants of water demand was developed.  The model allows to elaborate scenarios with a view to increasing agricultural revenues. Out of the 4500 planned surveys, 4139 surveys were conducted over two field campaigns and included a sample of 3000 farmers throughout the basin. The survey campaigns were preceded by a field training which included 40 technicians from different national institutions from the three partner countries. The surveys were conducted, verified and validated which helped to set up a large database integrating more than 800 000 socio-economic data. The analysis of these data highlighted the major elements that have a significant impact on the economic productivity of water:


  1. Ill-adapted pricing;
  2. Salinity and its impact on water productivity;
  3. Cropping systems by identifying the most adapted ones;
  4. Importance of livestock breeding in farmers’ income.
  5. Hydro-economic model

The hydro-economic model was developed with the aim of supporting decision-makers to design and implement agricultural development policies with a view to increasing agricultural revenues. The hydro-economic model operationalization was possible thanks to the global and micro-economic data collected and to the results obtained. The development of this model required a complementary survey campaign at the level of 647 collective water points.


  • Agricultural Demonstration Pilots

The “Demonstration Pilots” component aims at testing approved and irrigation-efficient technical solutions by the farmers for demonstration and replication purposes at the local, national and regional levels.
Six major issues related to unsustainable management of irrigation waters were identified and selected by the water authorities in the three concerned countries: 

Pilot 1: Safeguard of “foggaras” (traditional water catchment structures) and agricultural production systems in Reggane (Adrar, Algeria)
Objective: Strengthen the efficiency of ancestral irrigation systems and intensify oasis agriculture.
Activities: establishment of a localized irrigation system and implementation of two agricultural campaigns. The solar plant installed helped to increase the “foggaras” flow.
Results: ownership of the water-saving concept by the farmers. Significant quantities of water were saved thanks to localized irrigation and the abandonment of the « séguias » (highly permeable water channels which result in high water loss and infiltration).

Pilot 2: Improvement of water efficiency and reduction of water degradation in Wadi Righ in Algeria
Objective: Efficient irrigation, improved water quality and enhanced soil
Activities: Installation of a localized irrigation system and a buried drainage network. Two agricultural campaigns were conducted.
Results: Increase of agricultural yields, reduction of soil salinity (from 10g/l to 6g/l) and decrease of waterlogging translated in the decrease of 30cm of the aquifer level.   Agricultural production increased by 50%.  

Pilot 3: Restoration and safeguard of irrigated agricultural systems in the plain of Djeffara (Libya- Bir Etterfess)
Objective: Increase irrigation efficiency using brackish waters of 1,6 g/l ;
Activities: Installation of a localized irrigation system and implementation of two agricultural campaigns (off-season greenhouse crops and open fields).
Results: The agricultural productions systems introduced allowed to improve the farmers revenues by 80%.

Pilot 4: Use of geothermal waters in the irrigation of off-season crops in the zone of Oueds in the center of Libya (Merdoum, Zemzem):
Objective: Transfer a local know-how on the use of geothermal waters.
Activities: Given the difficult situation in Libya, this pilot was canceled and replaced by another pilot in Tunisia. The new pilot focused also on the use of geothermal waters for irrigation and the greenhouse technique. A related regional workshop was organized and was attended by nearly one hundred people including farmers, researchers, and journalists, etc.
Results: The awareness of decision-makers on the importance of geothermal waters for irrigation was increased. The experiment conducted within this pilot was replicated by other countries.

Pilot 5: Rehabilitation of irrigated lands affected by salinity and waterlogging (Oases of Jedida/Mansoura, Kebili) in Tunisia.
Objective: Rehabilitation of irrigated lands affected by salinity and waterlogging
Activities: Installation of a buried drainage network and water discharge system using solar pumping due to the absence of a natural slope for water evacuation.
Results: Drainage using solar pumping proved to be efficient as it led to the decrease of the aquifer level by 30cm and the reduction of soil salinity by 30%.  

Pilot 6: Rationalization of brackish waters use in irrigation in the Tunisian plain of Djeffera (region of Sidi Makhlouf, Medenine, and Tunisia) 
Objective: Desalinization of water for irrigation purposes
Activities: Installation of a localized irrigation system, a water demineralization station and two greenhouses.
Results: irrigated areas increased by 100%, more efficient irrigation and improved revenues.


  • Dissemination
  1. Development  of the SASS Website for a large dissemination of the SASS III results and recommendations
  2. Presentation of the SASS III results at the World Water Forum (South Korea, 2015) at the « Adaptation to Climate Change : Examples of Good practices” organized jointly by UNECE and the International Office for Water (OIEau)
  3. Dissemination and presentation of the SASSIII results at different international events (COP 12 to the UNCCD and COP 21 to the UNFCCC, 2015)
  4. Communication « Water management in arid areas: introducing social innovations and technical innovation in the NWSAS zone »  presented at the 26th Euro-Mediterranean Conference (Montpellier 2015)
  5. Dissemination of final reports and communication materials to different financial and technical partners (FFEM, GEF, UNESCO, FAO, GIZ, GWP-Med…), countries (national research institutions) and international research entities (IRD…)