How will water demand evolve between now and 2050?

This study, commissioned in the fall of 2023 by the Prime Minister, examines the theoretical changes in water withdrawals and associated consumption between 2020 and 2050, i.e., the portion of withdrawals that evaporates, according to three prospective scenarios. The first, called “trend”, extends past trends. The second, called “public policy”, simulates the implementation of recently announced public policies. The third, called “disruptive”, is characterized by water sufficiency.

Between 2020 and 2050, in the most unfavorable climate configuration studied, annual demand stagnates in the trend scenario (+1%) and decreases in the public policy (-24%) and disruptive (-47%) scenarios, particularly due to the decline in demand for energy production in the Rhône valley. The demand for irrigation increases sharply and becomes the majority. Unlike energy production, irrigation consumes the majority of the water withdrawn due to plant evapotranspiration. Consumption therefore increases substantially in the trend (+102%) and public policy (+72%) scenarios. In the latter scenario, they more than double in nearly a quarter of the catchment areas. Only the disruptive scenario limits the increase in consumption (+10% compared to 2020) in the most unfavorable climate configuration studied.

With the increase in the share of agriculture in water abstraction, the demand for water will be more concentrated during the hottest months of the year, when the water resource is at its lowest in aquatic environments. An upcoming publication by France Stratégie will quantify the tensions between available water resources and this demand.