The department enters alert status following several weeks of declining water levels and groundwater. The prefecture calls on each user to reduce their consumption to limit pressure on the resource and delay any potential restrictions.
The heavy rains that fell yesterday on the Alpes-Maritimes department have not changed the trend observed for several weeks. The drought alert remains in place due to progressive deterioration of the resource since the beginning of spring.
The prefect of Alpes-Maritimes, Laurent Hottiaux, has activated the first level of drought management. The decision came after an early decline in water flows and groundwater levels, with a level comparable to that usually observed two months later.
The period from September 1, 2025 to May 26, 2026 showed a cumulative rainfall deficit of approximately 15.5%, with some areas reaching -20%. In November, Laurent Hottiaux already warned about the issue. April recorded a deficit close to 87%. May remained deficit at -20%. Average temperatures exceeded normal levels since the start of the hydrological season. April 2026 ranked as the second warmest April since 1947. This situation intensified evaporation and evapotranspiration, with a direct impact on aquatic environments.
The decline in water levels accelerated from mid-April. Flow rates fell in all alert zones. The Artuby dropped to 294 l/s with an alert threshold of 200 l/s, compared to 706 l/s a year earlier. The Cagne reached 157 l/s with a threshold of 150 l/s, whereas the flow was near 800 l/s in late April 2025. The Estéron fell to 2,170 l/s with a threshold of 1,300 l/s, compared to 6,590 l/s the previous year. The Loup stood at 1,303 l/s with a threshold of 400 l/s, compared to approximately 6,000 l/s in April 2025. The upper Siagne showed 1,320 l/s with a threshold of 700 l/s, compared to 4,360 l/s in late May 2025. The lower Siagne reached 1,490 l/s with a threshold of 800 l/s, compared to 4,640 l/s in late May 2025. These data revealed a common trend: flow rates divided by two to five depending on the basins. The rapid snowmelt observed in the mountains supported certain areas, but this contribution remained temporary and limited.
Groundwater followed the same pattern. As of May 26, 2026, 70% of monitored groundwater levels were below seasonal norms. This situation confirmed lasting fragility of the resource.
A call for water conservation to delay any potential restrictions
The move to alert status does not include restrictions. The level aims to “encourage users and managers to achieve water savings in order to prevent or delay any further deterioration that might justify implementing restrictions.” The recommendations focus on domestic uses, watering, pool filling, outdoor washing and daily practices. The document emphasizes that “everyone is called upon to be vigilant and demonstrate civic responsibility and solidarity.” Local authorities are urged to reduce leaks, optimize green space watering, adjust cleaning practices and distribute water-saving equipment. Agricultural and industrial operators are encouraged to adapt their practices, particularly through water rotation, water-saving equipment or closed-loop systems.
The situation will be subject to continuous monitoring. Alert levels, enhanced alert or crisis levels may be activated based on changes in flow rates and groundwater levels. The departmental directorate of territories and the sea continues to implement the action plan initiated during the Water Assizes of January 23, 2023, in coordination with technical and institutional bodies.
