Land management and irrigation water rationalisation and valorisation in east-south Algeria: Oasis of Sidi Mahdi in Touggourt Valley (Oued Righ, Ouargla, Algeria).
Pilot overview
Georgaphical location: city of Ouergla, Touggourt region (Oued Righ Valley), Sidi Mahdi oasis, 5km east-south Touggourt.
Local irrigation problem: within the general context of water shortage, the improper management of irrigation water and drainage network resulted in the rise of the water table level, having as consequence the increase of soil salinization and hydromorphy, which had severe socioeconomic and environmental impacts.
Theme: Restoring hydromorphic soils and addressing salinization and improving irrigation water efficiency through the intensification of oasis systems.
Farming system: is based on date palms (deglet Ennour) and other food crops partly destined to local consumption.
Water resources: two main sources of water: the Continental Intercalary (CI) containing geothermal water and the Terminal Complex (TC) whose water resources are extracted by means of forages.
Irrigation water availability: the available water resources in Sidi Mahdi oasis can cover the agricultural needs of the region. Nevertheless, the improper water management resulted in local water conflicts and led to water deficiency.
Water quality: the water of the two tables (CI and TC) has an average salinity of 3-4g/l which would obviously lead to irrigated lands salinity.
Water management: irrigation water resources are managed by local agricultural associations. Open drainage systems located outside farms are managed by the National Irrigation and Drainage Office (l’Office National de l’Irrigation et du Drainage ONID).
Threats: soil salinization and hydromorphy, irrigation water deficiency, and the lack of maintenance of drainage networks are the major threats to the sustainability of Oued Righ oases.
System evolution: with the absence of a coordinated intervention from water actors to rationalise water resources management in the region, irrigation will be gradually abandoned and the oasis agricultural system will decline.