TOWARDS THE CREATION OF NEW OASES ALONG THE WADIS

Abstract

It is a paradox: why do we fail to take advantage of the prime agricultural land that Mother Nature has placed at our disposal? These are the soils found in the floodplains of the wadis, a vast, dense river network that remains unexploited. Yet, agricultural land is shrinking, sacrificed to urbanization that is accelerating in the wake of rapid population growth. The answer lies in the Sahara, as the oasis dwellers who lived in harmony with flash floods were the first to cultivate the soils of the wadis' floodplains. Between 1990 and 2026, we conducted fieldwork across the oases of the Algerian Sahara. Surveys and interviews were carried out with oasis inhabitants regarding sustainable water management and its impact on oasis agriculture. The study reveals that Algeria possesses a very dense hydrographic network, particularly within the Sahara. It also shows that, despite a climate hostile to life, farmers developed oases along the wadis. They succeeded in integrating the wadi and the oasis into a single unit, creating a unique ecosystem powered by flash floods: the active river channel ensures water security, while the floodplain ensures food security. So why not create new oases along the wadis today, thereby adapting to climate change? Flash floods are an invaluable gift from nature, replenishing the alluvial aquifer to allow for year-round irrigation. Moreover, these floods inundate gardens with nutrient-rich waters a natural fertilizer for agricultural land. Sustainable water management requires the construction of hydraulic structures such as subsurface dams, recharge dams, sand dams, and aquifer recharge stations.