CONCERTED WATER MANAGEMENT OF LARGE IRRIGATED PERIMETERS. CASE OF THE HABRA PLAIN (NORTH-WEST ALGERIA)

Abstract

The perimeter of Habra covers an area of 21210 ha, equipped on 19630 ha. Founded in 1940, it is part of the northern plain of the Macta in the Wilaya of Mascara. It is one of the most important perimeters of the Oran region. At the beginning of the 1960s, this perimeter received water quantities of around 80 million M3 / year. Since the creation of the Office that manages water from irrigated areas during the 1980s, the quotas allocated to irrigation of all irrigable areas did not exceed 32 million M3 / year.

This reduction, due to the insufficiency of the resource caused by the drought that has served over the Oran region for two decades and by the allocation of water in priority to domestic use.

The consultation between the irrigators' associations and the water management organization remains the only way and hope for farmers, allowing them to maintain their citrus orchards. Our surveys carried out with the public services and users, on the characterization of the agricultural plot of the Habra perimeter, on the supply and demand approach of which both actors are represented by ONID and irrigators, revealed The important role of the collective associations in a dynamic of concerted action that can be described as paralyzed, having the objective the surviving of the perimeter and transmitting their heritage to future generations. The collective network Of gravity irrigation is the only way to make subsist the citrus fruit orchards, some farmers resort to the purchase of water by tanks in order to maintain the survival of their farms. The functioning of the collective network is also greatly hampered by management deemed inefficient with a low level of maintenance. This places the perimeter in state of alert. This work illustrates the characteristics and mechanisms of water demands of farms, supply management and demand across the perimeter, managed by the national irrigation agency. The surveys realized that dam water remains the main water resource for the majority of farms in the perimeter, the water in the aquifer being highly saline, it can not under any circumstances provide for the irrigation of citrus fruits. Some farmers, often, having other incomes, have recourse to irrigation by the purchase of cisterns in order to maintain their orchards. The combined use of the two systems, collective network and tanks, makes it possible to irrigate about 30% of the cultivated area annually, this irrigation only allows the safeguarding of orchards and a low production of about 80 quintals/ ha.