الخلاصة:
In the semi-arid Mediterranean region, and more particularly in the Maghreb, the increased pressures on water resources (climate change, growing competition between users) are recognized as major issues. Rational water management is one of the challenges facing the Urban Grouping of Constantine (GUC) in northeast Algeria. Its water resources are renewable but limited, while the demand is constantly growing under the dual effect of population growth and increasing per capita needs. The Group is composed of five municipalities (Constantine, El Khroub, Ain Smara, Didouche Mourad and Hamma Bouziane) with a population of nearly 884,000 inhabitants in 2015, expected to reach 1.2 million inhabitants in 2030 and 1.8 million inhabitants in 2050 according to projections made by WEAP The mobilized resources provide a volume of drinking water supply of 117 million m3 of which 78 % is surface water and the rest is of underground origin. However, the volume billed is reduced to 47.3 million m3, a difference of -51% compared to the overall volume of water distributed (97 million m3). The rate of connection to the water supply network is over 80 %. The number of water leaks detected on the network has experienced a relative decline in 2015, the result of rehabilitation operations carried out at the level of urban centers. For the same year, SEACO statistics show that the hourly duration of water service increased in the GUC municipalities, reaching 18.3 hours per day and 74 % of households benefited from continuous distribution (24 hours per day). This improvement is mainly due to the increase in resources mobilized from the Beni Haroun dam. However, the spatial inequality in the supply of the GUC agglomerations remains effective. It is attributable both to the availability of the resource and to the management of hydraulic infrastructures. Also, satisfaction by mobilizable volumes may not be guaranteed in the long term, given sectoral competition, climatic hazards and the poor protection of resources. Modeling using WEAP (Water Evaluation and Planning System) has been performed. It is applied to evaluate and analyze the existing and expected resourcerequirement balance by 2050, according to future water resource management scenarios,
taking into account different exploitation policies and factors that may affect demand.
