Water in agriculture : understanding the challenges in the face of growing climate pressure
Faced with climate change, water availability is becoming a central issue for farmers. Although less than 10% of the useful agricultural area (UAS) is irrigated in France today, the pressure on this vital resource is constantly growing.
Between reduced rains, impact on agricultural production and technological or agronomic approaches, here are 6 essential elements to better identify water-related issues in the agricultural sector.
A decrease in summer precipitation by 2100
Climate projections based on the scenario of the reference warming trajectory for adaptation to climate change (TRACC) predict an average rise in temperatures of +2°C by 2030, +2.7°C in 2050, and up to +4°C by 2100.
Climate change is expected to cause a drop in summer rains of around 20%. This phenomenon would accentuate soil drying, with up to 15 to 27 additional days of drought expected by 2050 compared to the period 1976-2005.
In summer, evapotranspiration would increase, which would lower yields. This would require the use of more irrigation, as water is becoming increasingly scarce.
Agricultural yields threatened by water pressure
According to the France Strategy report published on January 20, 2025, which analyzes the prospects of water needs for human activities, irrigation represents one of the sectors where demand is expected to increase sharply.
In the absence of a disruptive policy, water needs for agriculture could increase by 72 to 102%, depending on the scenarios.
In addition, the General Council for Food, Agriculture and Rural Areas (CGAAER) forecasts a 23% increase in areas requiring irrigation.
Tensions related to the use of water are likely to increase, in particular with the management of drinking water, but also for industrial needs.
Precision irrigation: technologies to save up to 40% of water
New approaches make it possible to optimize water supply, in particular thanks to localized irrigation and management tools.
- Drip vs sprinkler : according to INRAE (National Research Institute for Agriculture, Food and the Environment), water gains of 10 to 30% in field crops, 20 to 25% in arboriculture and 5 to 15% in market gardening.
- Decision-support tools : weather stations, tensiometric probes and soil mapping could generate water savings of 10% to 40%.
Adapting crops : the genetic path
For several years, technical institutions such as Inrae and seed producers have been focusing their research efforts on the development of varieties that are more resilient to water stress.
“We will never be able to obtain plants that maintain their productivity without a high level of perspiration, so a compromise must be found between protection and productivity,” as pointed out François Tardieu, Research Director at the Laboratory for the Ecophysiology of Plants Under Environmental Stress at INRAE.
An agronomic approach to capture and retain water
The cropping system can be redesigned to slow water flow and limit erosion. Soil conservation agriculture improves soil structure and organic matter content, increasing soil water retention capacity.
According to agroclimatologist Serge Zaka, it is possible to increase water availability by 7 to 10 days. He also points out that the establishment of hedges is particularly beneficial, as they help to slow the flow of water.
Agrivoltaics : when shade and irrigation save water
Agrivoltaics, by combining agricultural and solar production, plays a strategic role in water management. By providing rotating and partial shade thanks to dynamic solar panels, this system reduces temperature differences and limits evapotranspiration.
Some devices such as those tested at Brouchy in the Somme and soon in Charente-Maritime, by TSE, a reference in agrivoltaics in France, are also integrating controlled irrigation. Result: up to 30% water savings thanks to this synergy between shading and technology.
To be read > Brouchy innovates with agrivoltaics and smart irrigation
Do you have an agrivoltaics project? Contact TSE, French solar energy producer.
