The District Water Commission (CDE), made up of 49 members, is the advisory body for the sustainable management of the department’s water resources and especially the management of drought periods.
The governor of Puy de Dom collected the CDE on Thursday, 23 June, given the deteriorating hydrological situation and the need to initiate restrictive measures.
This committee follows the decision issued on May 13, 2022 and the decision to activate vigilance across the department as of May 24, 2022.
Hydrological situation: deteriorating situation
Average monthly temperatures for the first six months of 2022 are higher than normal for the season and Météo-France indicates that the anomalous temperature is +2°C. In terms of rainfall, we are seeing a particularly dry start to 2022 and in particular May which is considered the driest on record with a deficit of over 70%. 2022 corresponds to the two driest years since 1976. Precipitation in June is almost normal but roughly thanks to the violent storm episode on June 2-4. Since June 8, there has been a lack of precipitation (except for the recent thunderstorms) and a sharp rise in temperatures with the heat wave starting from June 16-20.
Weather conditions have led to a significant decrease in river flows, especially since June 11. The levels of the Chaîne des Puys aquifers are low with a downward trend and the Allier placer aquifer levels show historically low values for this time of year.
The filling of the Sep reservoir at Combrailles, optimally at the beginning of the low-water season as it is filled to 100% of its capacity, makes it possible to secure agricultural irrigation in this sector. The filling rate of the Naussac Reservoir, which supports the low water level of the Allier River, is 69% at the end of June 2022, and its use in low water support must be careful to ensure water needs throughout the summer, even if the lack of rainfall persists. Thus, the governor of the basin has just asked all the governors of the departments involved to issue an order restricting the use of water on the Allier axis once the flow rate drops from 50 m3/s to the Gien hydrometric station in Loire, which is a flow. Which must be reached soon (depending on current storms and rainfall).
Measures: a deteriorating situation that requires initial restrictive measures
Taking into account all these elements, and in coordination with the neighboring departments regarding the inter-departmental basins, the Governor of Puy-de-Dôme decided, at the end of the exchanges in the CDE, to activate the restriction measures differentiated according to the state of the rivers.
Some areas of the department benefit from a less tense and vigilant state: the midwestern part of the department.
On the other hand, some other regions are already facing greater pressure on water resources and are now on alert, on high alert or even in crisis. Regarding the Allier axle, the alarm switch will be sounded once the 50m³/s flow has crossed the Gien, the same for the Bedat pool area for which the alarm can also be activated soon.
The classification of the 12 hydrographic regions of the department is as follows:
• Maintain the level of vigilance: Allier axis, Morge, Sioule, Allier upstream left bank (Couze Pavin), middle Allier on the left bank.
• Traffic at alert level: Allier downstream Left Bank, Dore, Alagnon
• Change to Enhanced Alert Level: Dordogne upstream and Ance Nord
• Crossing to CRISE level: Allier right bank and Cher upstream
These restriction measures will take effect from Saturday 25 June 2022.
Details by municipality can be found on the propluvia website http://propluvia.developpement-durable.gouv.fr/ which provides real-time information on the restriction measures being implemented on the national territory and hydrographic areas of the department.
Exceeding these thresholds leads to gradual restrictions on water withdrawal from the drinking water network and from surface water and associated groundwater.
For areas affected by the crisis threshold, all non-priority water uses are suspended. Only uses that meet the requirements of health, public sanitation, drinking water supply and irrigation are allowed to withdraw.
Restrictions and exemptions are included in the drought framework arrangement that the governor invites users to refer to.
The Governor, along with all water stakeholders, maintains a keen vigil regarding the deteriorating drought situation that the department has been experiencing since the beginning of the year.
Early preparation for the implementation of restrictive measures on several hydrographic areas of the department as well as on the Allier axis requires the commitment of everyone in terms of the measures taken, in order to avoid passing to the second level as much as possible. Restrict, aggravated alert, in the coming weeks. It is up to each of us to demonstrate sobriety and economy in our use of water, even on an alert level.
Reminder of the four selected measurement levels
• Threshold of Vigilance: Inform and encourage individuals and professionals to save water.
• Alert threshold: Initiation of the first restriction actions for certain activities, or even the first bans. The cuts are also for economic uses with the goal of reducing withdrawals by 25%;
• Increased alert threshold: Gradual restriction of recalls and significant enhancement of procedures to limit or suspend use if necessary. The cuts are also for economic uses with a target of 50% reduction;
• Crisis threshold: All withdrawal and demobilization restrictions are implemented. All non-priority water uses have been suspended.
Look for a river basin classification to implement water use restriction measures after the District Water Committee on June 23, 2022
The following are the restriction procedures by alert level: