What happens when a municipality actually starts to run out of water?

Usage restrictions are the most visible part of a drought: limitations on watering, bans on filling certain swimming pools, restrictions on washing vehicles, or reductions in certain agricultural and industrial withdrawals.

But for local authorities and network operators, another challenge is unfolding in parallel: continuing to guarantee access to drinking water when the available resource decreases.

In September 2026, this question is far from theoretical. According to the BRGM, as of September 1st, 61% of groundwater observation points showed levels below monthly normals, and 90% were still declining. The situation is more degraded than at the same period in 2025.

The Ministry of Ecological Transition also describes the summer of 2026 as a period of early and severe drought. In some territories, the issue is therefore no longer just about reducing consumption: it is also necessary to anticipate situations in which the usual drinking water supply becomes insufficient.

Network interconnections, mobilization of new resources, storage, tanker trucks, bottled water distribution, or mobile treatment units: how can a local authority secure its supply during a drought? FLX Water takes stock.

Drought 2026: what is the state of water resources in France?

After several months of rainfall deficit and high temperatures, the groundwater situation remains difficult at the end of the summer of 2026.

The bulletin published by the BRGM on September 8th indicates that the summer depletion of aquifers continued in August. Levels were down at 90% of observation points, stable at 8%, and up at only 2%.

In total, 61% of levels were below monthly normals, compared to 44% at the same period in 2025.

However, the situation is not uniform across the territory. Some aquifers maintain satisfactory levels while others show very low levels, particularly in certain areas of the Limousin, the Jura, or the Alsace plain.

This territorial difference is essential. A national drought does not mean that all municipalities have the same level of resources or face the same difficulties.

The BRGM also points out that groundwater plays a major role in the country's supply: in mainland France, it accounts for nearly two-thirds of drinking water consumption.

A prolonged drop in groundwater levels therefore constitutes a direct issue for municipalities that depend on underground catchments.

In the short term, autumn rains can help improve some situations, but their effect is neither immediate nor uniform. In particular, the soil must be sufficiently rehydrated before effective recharge of the aquifers can take place.

Water restriction and supply disruption: what is the difference?

A municipality placed under water restrictions is not necessarily a municipality that is running out of drinking water.

The objective of the restrictions is precisely to avoid reaching that situation.

The French drought management system is based on different levels of severity, allowing measures to be progressively adapted to the local situation. Depending on the level reached, certain types of consumption may be limited or prohibited in order to preserve the resource.

The national guide for implementing restriction measures, amended in July 2026, recalls that the system must make it possible to protect priority uses, which include health, civil security, and drinking water supply.

Restriction is therefore first and foremost a tool for preventive management.

A supply disruption corresponds to a different stage: despite the conservation measures and the securing solutions put in place, the usual system is no longer capable of providing enough drinking water to all users.

This distinction is fundamental for local authorities: managing a drought does not consist only of publishing restrictions. It is also necessary to prepare for the continuity of the water supply if the situation deteriorates.

How can a drought weaken the drinking water supply?

The most intuitive consequence of a drought is the reduction in the quantity of available water.

When an aquifer drops, a catchment may produce less water. A stream may reach a very low flow rate. A spring used by a small municipality can also lose a significant part of its flow.

But quantity is not the only issue.

A prolonged drought can also change the conditions under which the resource is exploited and treated. A decrease in flow rates can, for example, reduce the dilution of certain substances present in the environment.

Depending on local characteristics, variations in water levels can also change the quality of the raw water collected.

For a local authority, the problem can therefore become twofold:

• having a sufficient volume of water;
• having water that can be treated to reach the quality required for human consumption.

To this are added the constraints specific to the distribution network.

In a situation of extreme shortage, a significant drop in pressure or an interruption of the supply can complicate the sanitary management of the network. The return to service must then be controlled in order to avoid the risks of contamination.

Securing drinking water must therefore be thought of as a complete chain: resource, treatment, storage, distribution, and backup solution.

How can a local authority secure its water supply?

There is no single solution applicable to all municipalities. The strategy depends on the territory, available resources, population size, the existing network, and the duration of the crisis.

However, several levels of response can be combined.

1. Reduce losses on the network

The first available resource is sometimes the one that is already being withdrawn but is not reaching the user.

Searching for and reducing leaks therefore constitutes a major structural lever for securing the supply.

The National Water Plan, moreover, places the reduction of leaks among the actions that allow for securing the drinking water supply.

These investments obviously do not constitute an emergency solution when a municipality is already close to disruption. On the other hand, they make it possible to reduce its vulnerability before the next periods of tension.

2. Interconnect networks

Interconnection consists of allowing a drinking water network to be supplied, temporarily or permanently, by another network.

When a local resource becomes insufficient, a municipality can thus benefit from the capacity available in a neighboring territory.

The Ministry of Ecological Transition explicitly cites network interconnections among the first security solutions to be mobilized before switching to an emergency supply.

This strategy, however, assumes that the infrastructure has been planned in advance and that the mobilized resource is itself available.

3. Diversify resources

Depending on a single catchment mechanically increases the vulnerability of a territory when a drought or pollution affects that resource.

The mobilization of other catchments, complementary resources, or storage solutions can therefore strengthen the resilience of the system.

This diversification must be prepared before the crisis: a new resource intended for drinking water production cannot be mobilized without an assessment of its quality, any necessary authorizations, and adapted treatment.

4. Anticipate priority needs

Not all uses have the same priority in a situation of shortage.

Drinking water supply, health, and civil security are among the uses to be preserved.

A local authority must therefore be able to identify in advance the essential volumes and sensitive sites: the general population, health establishments, nursing homes, schools, reception structures, emergency centers, or other essential infrastructure.

This mapping then makes it possible to size the necessary means in case of network interruption.

What happens when the network can no longer provide enough drinking water?

When the solutions for maintaining the supply through the public network have been exhausted, the local authority enters into a logic of substitute supply.

The Ministry of Ecological Transition identifies three main solutions in particular:

• the distribution of bottled or bagged water;
• supply by tanker trucks authorized for the transport of food products;
• the production of water using mobile treatment units.

Mayors and those responsible for the production and distribution of water are in charge of this substitute supply according to the needs and the minimum quantities provided for the different categories of users.

However, these solutions do not meet the same constraints.

Bottled water: simple to distribute, heavy to supply

Packaged water has the advantage of being able to be quickly distributed to the population.

But when a crisis concerns several hundred or several thousand people for several days, the volumes quickly become considerable.

It is necessary to transport pallets, organize their storage, define distribution points, mobilize staff, and then manage the packaging waste.

Tanker trucks: transporting large volumes

Tankers make it possible to transport more water in a single rotation.

However, they remain dependent on an available external resource, a suitable vehicle, a passable route, and continuous logistical organization.

The longer the crisis lasts, the more important the issue of rotation frequency and distance to the filling point becomes.

Mobile treatment units: producing water locally

A third approach consists of exploiting a resource available on-site and treating it using a temporary or mobile unit.

The principle then changes: instead of transporting all the necessary water to the population, one moves a treatment capacity to the resource.

This approach can be particularly interesting when fresh surface water is accessible but cannot be consumed directly.

Treating water on-site: a solution to reduce logistical dependence

When a river, lake, reservoir, or other compatible resource remains available nearby, local water production can complement other emergency measures.

This logic is of particular interest for isolated communities or when a crisis is prolonged.

It is precisely for this type of situation that FLX Water has developed its Crisis Solution.

This mobile unit is designed to allow the treatment of fresh surface water in the field, when the characteristics of the resource are compatible with the device.

It can treat up to approximately 1,000 liters of water per hour and operates using a manual pump. It therefore requires neither electrical power nor the addition of chemicals to ensure its filtration process.

The system is based on several successive filtration steps allowing the water to be treated before its distribution.

This autonomy is of particular interest in a crisis management approach: a power cut or the absence of a functional energy infrastructure does not prevent the use of the unit.

The solution can notably be mobilized in contexts of temporary network failure, natural disaster, isolation of a population, or punctual need for water supply.

However, it does not constitute a universal response to all shortages.

The FLX Water Crisis Solution is notably not a desalination system. Seawater cannot therefore constitute its input resource. Likewise, the quality of the available resource must be assessed in order to verify its compatibility with the intended treatment.

For a local authority, the value of a mobile unit is therefore not to replace the public network but to constitute an additional capacity that can be mobilized when the usual operation is compromised. The FLX Water Crisis Solution can thus be integrated among the anticipated means to ensure a temporary water supply.

Why should emergency solutions be anticipated before the disruption?

A water supply crisis is much more difficult to manage when the first decisions are taken once the catchment is already exhausted.

The experience of the 2022 drought showed this on a large scale.

According to the interministerial feedback published by the Ministry of the Interior, more than 2,000 municipalities in metropolitan France had to resort to alternative solutions in an emergency to distribute drinking water to all or part of their inhabitants.

Seven municipalities had even found themselves completely destitute for several days, while several large cities or metropolitan areas had been close to disruption.

This feedback had notably highlighted the need to improve anticipation, crisis management, and territorial solidarity.

Preparation can therefore consist of:

• identifying the emergency resources available in the territory;
• knowing the capacities of existing interconnections;
• mapping priority populations and establishments;
• planning for storage and distribution means;
• identifying bottled water suppliers and available logistical capacities;
• planning for tanker transport means;
• identifying resources that could potentially be treated locally;
• having mobile solutions available that can be quickly deployed.

The objective is to have several scenarios rather than a single backup solution.

ORSEC, PCS: integrating water into crisis preparedness

Securing the supply does not solely come under technical network management.

It is also part of the broader preparation of territories for emergency situations.

The ORSEC system organizes the civil security response under the authority of the prefect and allows for the coordination of the public and private means necessary during a crisis.

The ORSEC doctrine includes tools relating to the restoration and emergency supply of essential networks, including water.

This system also links with municipal safeguard plans (PCS) and inter-municipal safeguard plans.

For local authorities, the challenge therefore consists of not considering water disruption as a purely theoretical scenario.

Which neighborhoods should be supplied in priority? Where should a distribution point be installed? How many liters need to be transported each day? What alternative resources are available? What equipment can be deployed? How long can they function?

These questions are much easier to resolve when they have been asked before the start of the crisis.

From crisis management to territorial water resilience

Successive droughts show that securing drinking water can no longer rely solely on a punctual response during the summer period.

The National Water Plan is precisely part of a broader logic of resilient and concerted management of the resource.

Among the identified axes are sobriety of use, reduction of leaks, valorization of certain non-conventional waters, mobilization of existing resources, and improvement of the response to drought crises.

The water resilience of a territory therefore relies on several complementary levels:

Preserve the resource. Reducing avoidable consumption and losses makes it possible to limit the pressure on catchments.

Diversify the supply. Interconnections and complementary resources allow for reduced dependence on a single catchment.

Monitor quantity and quality. Having water is not enough: this water must be able to meet the requirements necessary for the use for which it is intended.

Prepare substitute solutions. Tankers, packaged water, and mobile treatment units make it possible to maintain access to water when part of the usual system becomes unavailable.

For FLX Water, this last dimension is essential: crisis management does not begin on the day the water stops flowing from the tap. It begins with the identification of resources, risks, and solutions that can be quickly mobilized if the network is weakened.

Drought: anticipating disruption rather than suffering it

Water restrictions constitute an essential response when the resource becomes scarce. But they only represent one part of the strategy.

For a local authority, true security consists of being able to maintain access to drinking water even when a resource or a usual infrastructure becomes unavailable.

The experience of 2022 and the situation observed in 2026 show that this scenario is no longer exceptional enough to be ignored.

Reducing leaks, interconnecting networks, diversifying catchments, and preserving the resource constitute the priority structural responses. But when they reach their limits, substitute supply means must be able to take over.

Packaged water and tanker trucks will remain essential in many situations. When local conditions permit, a mobile treatment unit can supplement these methods by enabling water production directly near the affected population.

With its Crisis Solution, FLX Water fits precisely into this approach: providing local authorities and crisis management stakeholders with an autonomous treatment capacity that can be deployed when standard access to water is compromised.

Because in the face of droughts, the question is no longer just how to consume less water. It is also about knowing how to continue providing it when the usual resource is no longer sufficient.

Frequently Asked Questions

Does a water restriction mean a municipality is at risk of running out of drinking water?
Not necessarily. Restrictions are precisely intended to reduce certain uses in order to preserve the resource and priority needs, including drinking water supply. A shortage occurs when available resources and backup solutions are no longer sufficient to maintain a normal supply.

Who is responsible for organizing the water supply in the event of an outage?
The Ministry of Ecological Transition specifies that mayors and those responsible for water production and distribution are in charge of providing substitute water supplies for populations when the network can no longer ensure access to drinking water.

How can a municipality distribute water if its network is no longer working?
Among the solutions identified by the State are the distribution of bottled or bagged water, supply via tanker trucks authorized for the transport of food products, and water production using mobile treatment units.

Can a river be used as a source of drinking water in an emergency?
River water should not be considered drinkable without appropriate treatment and testing. Depending on its quality and the equipment used, surface freshwater can, however, constitute a resource to be treated in the context of an emergency supply.

Does the FLX Water Crisis Solution work without electricity?
Yes. It uses a manual pump to provide the pressure required for its operation and requires neither an electrical power supply nor the addition of chemicals for its filtration process.

Can it filter seawater?
No. The FLX Water Crisis Solution is not a desalination system. It is intended for freshwater resources compatible with its treatment process.

Sources

• BRGM – Groundwater levels as of September 1, 2026
  Bulletin published on September 8, 2026: 90% of monitored levels are declining and 61% are below monthly normals. The BRGM also details regional disparities and outlooks for the autumn.
• Ministry of Ecological Transition – Everything you need to know about drought
  Overview of the 2026 drought, restriction measures, and substitute supply solutions in the event of an outage: packaged water, tanker trucks, and mobile treatment units.
• Ministry of Ecological Transition – Drought Guide: Implementation of water usage restriction measures
  National guide amended in July 2026 specifying the drought management framework and the preservation of priority uses.
• Ministry of Ecological Transition – Action plan for resilient and concerted water management
  Presentation of the Water Plan and its 53 measures focusing on sobriety, leakage, resource availability, and response to drought crises.
• Ministry of the Interior – Feedback on water management during the 2022 drought
  Interministerial report indicating that more than 2,000 metropolitan municipalities had to resort to alternative solutions to distribute drinking water during the 2022 drought.
• Civil Security – ORSEC: The Prefect's crisis management tool
  Presentation of the ORSEC system, its integration with communal safeguard plans, and tools dedicated to the restoration and emergency supply of essential networks, including water.