17 Juillet 2026

Fire Water Storage Tanks: French Regulations and Requirements in 2026

Installing a fire water storage tank is mandatory for many construction and industrial projects in France. Whenever the public water network cannot provide sufficient fire‑fighting flow, a dedicated fire water supply must compensate. In 2026, understanding regulatory obligations related to site safety is essential to obtain permits and protect assets.

Key Takeaways

It provides an artificial water source for firefighting operations.
It is part of the French external fire protection framework (DECI).
The minimum required capacity is 30 m³, but the SDIS may require more.
Obligations depend on the building type, location, and risk level.
It may be imposed as a condition for obtaining a building permit.
It must be maintained, signposted, and inspected regularly according to compliance standards.

Definition and Role in External Fire Protection

Before addressing obligations, here is what a fire water storage tank is and why it exists.

General Definition

A fire water storage tank is a dedicated water storage system designed to supply fire‑fighting equipment. It is considered a fire‑water point (PEI) under DECI regulations, with strict requirements for capacity, accessibility, and equipment.

It can take several forms: flexible tanks, bolted steel tanks, concrete basins, or underground tanks. The choice depends on site conditions and recommendations from the local fire and rescue department (SDIS).

Role in External Fire Protection

The external fire‑protection system ensures that firefighters have a water supply under all circumstances. When the public drinking‑water network cannot provide the required fire‑fighting flow, the private reserve takes over. Without this supply, emergency response is slowed down or compromised.

Regulatory Framework in France

Several regulations govern fire‑water reserve compliance obligations. Knowing them is essential for meeting regulatory requirements.

Decree No. 2015‑235 (27 February 2015)

This decree reformed external fire protection (DECI). It replaced older circulars with a risk‑based approach. It is complemented by the Order of 15 December 2015, which governs reserve sizing and inspection procedures.

Departmental Regulation (RDDECI)

Each French department has its own DECI regulation, prepared by the local SDIS and approved by the Prefect. The applicable rules applicable to your project depend directly on this document and must be consulted before any project begins.

Role of the SDIS

The SDIS is the technical authority. It determines the required capacity and validates the suitability of the fire‑water point. Without its approval, a private reserve cannot be integrated into the municipal DECI system.

Who Is Subject to the Obligation?

Obligations vary depending on the building type, location, and risk level assessed by the SDIS.

Industrial Buildings and Warehouses

These are the most affected. Required flow rates often exceed 60 m³/h for 2 hours. The fire‑water tank must remain accessible to emergency vehicles at all times.

Public Buildings (ERP) and Tertiary Facilities

Public‑access buildings must have an adequate fire water reserve. Criteria vary depending on the surface area and local SDIS recommendations.

Agricultural and Rural Areas

In rural zones, pressurized public water networks are often absent. Agricultural sites frequently need a private fire water tank. In rare cases defined by the RDDECI, the SDIS may grant an exceptional exemption for very low‑risk isolated buildings — but this is never a default option.

Sizing Parameters and Method

Sizing a fire water tank is based on technical parameters, not on fixed values.

French regulations require a minimum of 30 m³. Common thresholds include:

Risk Type	Reference Volume	Nominal Flow
Low risk (rural housing)	30 m³	30 m³/h
Standard risk (craft/workshops, SMEs)	60–120 m³	60 m³/h
High risk (industry)	120 m³+	60–120 m³/h
Special risk (ICPE)	SDIS study	Specific analysis

Flow Calculation

The nominal flow corresponds to the simultaneous flow required by fire‑fighting vehicles. Pump and suction line sizing must follow the Ministry of the Interior’s D9 guide.

Supply Duration

The reference duration is 2 hours. Combined with the required flow, it determines the necessary tank capacity. Longer water autonomy may be required for specific risks.

Fire Water Storage System and Building Permits

The tank must be planned during the design phase, before submitting the building permit application.

When Does It Become a Permit Condition?

If the plot is not covered by the municipal DECI scheme, a private fire water point may be required. Without regulatory compliance, the municipality may refuse to issue the completion certificate.

Accessibility and Installation Requirements

The installation must meet the following criteria:

A maximum distance of 400 meters between the supply point and the building
An all‑weather drivable access road
A stable, clear hardstanding area
Clear and visible signage

Compliant Technical Solutions

Several solutions meet DECI obligations. The choice depends on site characteristics and risk assessment.

Bolted Steel Tank

A bolted steel tank is a versatile solution for fire water storage. Manufactured in the factory and assembled on site, it can accommodate capacities from a few dozen to several thousand cubic meters. Since 1987, APRO Industrie has been designing and installing self‑supporting fire water tanks compliant with regulatory requirements.

Fire‑Fighting Manifold (Nourrice Pompiers)

Every APRO tank is equipped with suction points sized according to SDIS recommendations. The manifold (a multi‑outlet collector allowing several fire engines to draw water simultaneously) is integrated from the design stage. This is a key technical advantage ensuring efficient water extraction even during multi‑hose operations.

Available Finishes

Standard galvanization for most environments
Magnelis or C5 paint for ICPE sites or corrosive environments (marine, chemical industry)

APRO Industrie masters all three corrosion‑protection levels and recommends the most suitable option for each site.

Fast Installation

Unlike concrete basins requiring heavy civil works (excavation, formwork, curing time), APRO bolted tanks are assembled in a few days. This provides a significant advantage for projects with tight permit deadlines or rapid commissioning needs.

Choosing the right solution depends on the required capacity, terrain type, installation timeline, and local regulatory constraints. Flexible tanks suit large temporary capacities. Underground tanks are suitable for urban environments.

Mandatory Maintenance and Inspections

A compliant tank must remain operational at all times, requiring rigorous follow‑up.

APRO Industrie supports clients well beyond installation. We perform periodic regulatory inspections: checking available volume, suction equipment condition, manifold integrity, and watertightness. This simplifies operations for site managers, who benefit from a single point of contact for installation and ongoing regulatory compliance.

APRO also offers cleaning and inspection using an ROV (remotely operated underwater robots), allowing internal inspection without draining the tank. This method detects deposits or deterioration while maintaining operational availability.

Discover Our After-Sales Service

Regulatory Periodic Checks

The operator must carry out periodic inspections covering available capacity, suction equipment condition, and pressure. Authorities may conduct unannounced inspections.

Maintenance Logbook

A maintenance logbook must record all interventions. It may play a decisive role in insurance procedures in in the event of an incident.

Responsibility

The mayor is responsible for public DECI systems. The private owner is responsible for installing the prescribed fire water tank. In case of an incident, the owner may incur civil and criminal liability.

Fire Water Tank FAQ

Which regulations govern these installations in France?

Decree No. 2015‑235 and the Order of 15 December 2015. Each department has its own RDDECI specifying local rules.

What is the minimum required capacity?

30 m³ minimum. The SDIS determines the exact volume based on building type and risks. Industrial sites typically require 60–120 m³.

Who is responsible for installation?

The mayor for public DECI. The project owner is responsible when a private reserve is required for the building permit.

Is it mandatory for all building permits?

No. Only when the plot is not covered by a compliant existing fire water point, after SDIS consultation.

What is the difference between a hydrant and an autonomous tank?

A hydrant is connected to the pressurized public network. A fire water tank is an autonomous storage system from which firefighters pump water when the public network is insufficient.