Regulatory measures

Modifié le 19/11/2015


It is sometimes difficult for citizens to understand all the regulatory measures in force relating to civil security. Each level of decision-making has its own flood risk planning and management system. Let's try to clarify things

ORSEC system

The ORSEC (Civil Security Response Organization) system is the "toolbox" of civil security, combining a set of procedures and operational tools.
It is divided into two parts. An administrative and technical process of analysis, inventory and research, which has resulted in a permanent operational organization, the ORSEC system. This system can be departmental, zonal or maritime. The zonal ORSEC brings together all the support actions that the zone can give to the local departments.
It is organized around the competent Prefect (Prefect for the department or the zone, or maritime Prefect), and relies on a large network: SAMU [Emergency Medical Services], SDIS [Departmental Fire Rescue Service], police, gendarmerie [military police], associations, local authorities and businesses.
The major innovation of the Law on the Modernization of Civil Security in August 2004 is that the ORSEC system is now permanent, and based on an increased level of response , not a simple reaction to a crisis.
Some risks are known, and therefore have been made into scenarios, but others cannot be planned for. ORSEC nevertheless offers a range of tools adaptable to all situations.

For this reason, the system is divided into two types of measures :

  • General measures which determine an operational response to all types of risk, related both to prevention and the organization of assistance. The general measures are the backbone of the ORSEC system, setting out the command structures, and the principles of crisis communication and public information.
  • Specific measures determining the operational response to a specific, previously identified risk, and identifying where necessary the general measures related to the existing phenomenon. The flood risk is one of these, and is the subject of a specific zonal measure. The drafting of a Specific Flood Measure in the zonal ORSEC is an obligation required by both European and national legislation (Law on the Modernization of Civil Security of 13 August 2004 and the Internal Security Code). This measure organizes the response in the event of a major flood, by defining the aims of intervention and crisis management in all sectors. The current measure dates from 2010. It is currently being redrafted by the Secretary General of the Paris Defence and Safety Zone, which hopes to use Sequana in order to update it. This is the measure which sets out how the exercises are organized and how feedback on the experience is collected.


Flood risks management strategy

In line with European legislation, a Preliminary Flood Risk Assessment (Évaluation Préliminaire des Risques d'Inondation - EPRI) has been produced for each large river basin, in order to select the Significant Risk Areas and establish three mapping categories :

  • frequent phenomena,
  • average phenomena,
  • extreme phenomena.

This mapping helps to analyze the vulnerabilities of the zone, in terms of its socio-economic functioning: exposure of sensitive establishments (hospitals, schools, Seveso-classified businesses), strategic locations of road networks, sensitivity of the energy, drinking water and sanitation networks etc.


Several texts for managing flood risks will also be produced :

  • at national level, with the National Strategy for Managing Flood Risks, approved on 7 October 2014;
  • at river basin level, with the Flood Risk Management Plans (Plans de Gestion des Risques d'Inondation - PGRI). The Ile-de-France is included in the Seine-Normandy PGRI, which includes 16 Significant Risk Areas (TRI) (see map below).

Carto TRI

Significant Flood Risk Areas (TRI) in the Seine river basin and Normandy coastal water courses

Significant Flood Risk Areas (TRI). Limits of the Seine Normandy river basin.

The PGRI are subject to public consultation, which will take place from 19 December 2014 to 18 June 2015. They will be finalized at the end of 2015, under the direction of the Coordinating Prefects for the River Basin.

For more information

At the level of the "Ile-de-France metropolis" TRI, i.e. 141 municipalities in the Ile-de-France, with the drafting of a  Local Strategy for Flood Risk Management (Stratégie Locale de Gestion des Risques d'Inondation - SLGRI) , which must be approved by December 2016. This involves producing a diagnosis shared by all the stakeholders, accompanied by the targets to be attained.


Created in 1995 and reformed in 2003, the  Flood Risk Prevention Plan (Plan de Prévention du Risque Inondation - PPRI) is enshrined in the French Environment Code under natural risk prevention plans.

Drafted under the authority of the Prefect of the Department, this town planning document maps the risk areas and determines any prohibitions or restrictions on human settlement. It also sets out protective measures aimed at local authorities and individuals. The PPRI is a public easement and is appended to the Local Town Plan (Plan Local d'Urbanisme - PLU).

For more information

Public service establishments located in a flood-risk area are required by the Paris PPRI to draft a Flood Protection Plan. This sets out their flood prevention measures (using the 1910 flood as a reference).


The Business Continuity Plan (Plan de Continuité d'Activité - PCA) contains measures aimed at ensuring the continuation, according to various crisis scenarios, of the essential activities of the service concerned (business or administration), and organizing the full resumption of these activities.

This is compulsory for Essential Operators (Opérateurs d'Importance Vitale - OIV) and strongly recommended for all administrations and businesses.

Several businesses are recognized as Essential Operators, due to the crucial role they play in economic life and society. These are businesses whose operation cannot be interrupted, as this would seriously compromise the country's economic operation.

For more information


The preoccupation of the public authorities with precise, practical, transparent public information on natural and technological risks is relatively recent. It is set out in the following documents, made available to the public :

  • The Departmental Major Risks Report (Dossier Départemental sur les Risques Majeurs - DDRM) is an inventory of the major risks to which the population is subject, at local department scale. It is drawn up under the authority of the Prefect of the Department. It contains the list of affected municipalities, general information on all the natural and technological risks identified in the area and a summary of the prevention measures for each risk.
  • The Municipal Major Risks Information Report (Dossier d'Information Communale sur les Risques Majeurs - DICRIM) is a document drawn up under the authority of the Mayor of a municipality (commune). It is both a register of information on the risks likely to affect the municipality and a general inventory of individual and collective conduct to be followed. Using the information contained in the Departmental Major Risks Report, the Mayor produces a Municipal Major Risks Information Report which summarizes the consequences of a major event on people and property and sets out the individual and collective measures to be taken to minimize the effects.
  • The Mayors must draw up a Municipal Safeguarding Plan (Plan Communal de Sauvegarde - PCS) in order to organize alerts, transport and accommodation of affected populations, ensure the continuity of essential services and set up a municipal crisis unit.