The Continental Intercalary in Algeria: Analysis, Survey and Perspectives for Green Agriculture Development

Abstract

The Northern Sahara Aquifer System (NSAS) is a complex system that includes several aquifers overlying most areas. The Continental Intercalary, also known as the "Albian groundwater" is an aquifer with impressive characteristics. It extends over three countries: Algeria, Tunisia and Libya. Intended for crop irrigation, the boreholes drilled in this Algerian aquifer, the boreholes carried out on this aquifer are artesian in their totality, with flows and pressures reaching in some places considerable values, of the order of 0,4 m3.s-1 for the flow and 3.106 Pa for the pressure. These two parameters are necessary to appreciate the energy potential of the Albian groundwater. A survey of the Continental Intercalary was carried out to study its energy potential. We were able to gather all possible data concerning the boreholes in the Algerian aquifer part. The study covered 295 boreholes that were identified and well documented, spread over 3 regions in southern Algeria. The water from the artesian boreholes in the Albian groundwater is transported to storage basins (for drinking water supply, irrigation and industry) for later use, or distributed directly to users after lowering the temperature of the water in the cooling towers. In these operations, all the hydraulic energy is lost and external energy is required from the electricity grid to meet the needs. The cumulative energy potential of all the boreholes identified has reached the theoretical value of 168GWh/year, the equivalent of 14520 toe (ton of oil equivalent) that are lost annually. Best management of this natural resource will not only enable resilient and sustainable management of the production systems and the environment, but also the energy needed to cool the water, as well as the energy needed for the maintenance of the boreholes and the facilities in the direct neighbourhood.