The public irrigated schemes (PPI) of the Lower Medjerda Valley (BVM) were put in place almost 60 years ago and cover an area of ca. 27,000 ha. The infrastructure originally installed (the Laaroussia canal, the pumping stations, the gravity-fed water intakes, the canal networks, etc.) is now largely dilapidated. The modernization of the perimeters is essential to preserve existing perimetres and improve farming conditions for agriculturalists. At the same time, achieving both rational and sustainable use of the water resources available in the region remains a key objective.

For the modernization measures to be completed, both spatial and temporal planning must be carried out. Moreover, the capacity of the Laaroussia Canal to meet the future irrigation water needs of those modernized perimetres fed by the canal, must also be gauged. This justifies a study which prepares a master plan for the modernization of the PPI of the Lower Medjerda Valley. Such a master plan must serve as a coherent and credible tool for planning future modernization projects up to 2035. In addition, it should provide the necessary technical foundation to guide and justify the actions required for the restoration and the modernization of the Laaroussia Canal.

The project was implemented in two phases and entailed the following components:

Phase 1: The development of  a master plan for the modernization of the PPI under command of the Laaroussia Canal. The Master Plan aims at providing a coherent planning tool for the modernization over the next two decades of the lower Medjerda Valley irrigation area comprising 19 schemes with close to 27,000 ha irrigated land. The Plan is developed through a participative and consultative approach involving all actors ; different government entities as well as farmer representatives and other stakeholders in the use (and abuse / pollution) of land and water resources. The first step is a pre-diagnostic study of the canal system and the irrigation schemes which aims at identifying the major issues on the basis of available information and orient further investigations like topography, water availability (surface-, ground- and waste water), soil studies, infrastructure (canals, irrigation schemes, pumping stations), environmental surveys, user questionnaires, etc.). These further investigations formed the basis for a detailed and multi-disciplinary diagnostic study which was presented by means of thematic maps, regrouping different criteria and indicators (land, irrigation, infrastructure, drainage, agricultural production, institutional framework, urbanization, environment, financial and economic analysis). The diagnostic study allowed the subsequent development and prioritization of a series of development and rehabilitation scenarios for the Laroussia canal and the irrigation schemes as per a multi-criteria analysis. This strategy document was then, during the last stage of the phase 1, converted into an action plan which not only dealt with the sequence, the approach and the programming of the rehabilitation of the canal and the irrigation schemes but also with the accompanying measures at irrigation scheme level as well as key cross-cutting issues. Amongst the latter were identified the issues of land tenure, urbanization, water resources planning and management, agricultural sector support, and the formulation of an environmental and social action plan.

Phase 2: The carrying out of a feasibility study (preliminary design) for the rehabilitation of the canal and its regulation system and the enlargement of its transport capacity with the primary objective of determining rehabilitation requirements of the Canal taking into account the technical and economic feasibility of measures. A study of the canal regulation system was also included in the study, which aimed at satisfying the future water requirements of irrigation schemes and ascertaining the hydraulic performance of the canal during different periods.