3. Surface water quality monitoring - summary: France

Page Last modified 29 Sep 2017
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France covers 543,964 km2 and has a population of 56.7 million (1990). The total river length is around 273,000 km of which the majority are small creeks, only about 35,000 km of the rivers being more than 1 meter wide. The major river systems in France are the Loire, the Rhône, the Seine and the Garonne covering 62 per cent of the French territory. The exact number of lakes is unknown, but the numbers of fresh and brackish waterbodies have been estimated to be 9,800 and 690, respectively. The largest lake is Lac Léman shared with Switzerland. France has coastline along the North Sea, the English Channel, the Atlantic Ocean and the Mediterranean.

Monitoring of rivers

Involved institutions

The national surface water network is based on six basin agencies acting under the general supervision of the Ministry of Environment, each agency managing a national basin network, RNB (Réseau National de Bassin). As a general principle, sampling frequencies, lists of water components to be analyzed, and analytical methods to be used are directly determined by the subsequent users of data.


The purpose of the RNB is to provide a set of reliable data related to French inland surface waters. RNB does not constitute the total of measured and available data, since many other organizations perform water composition measurements; nevertheless, it aims at being the permanent reference in its field.

Organization and coordination

The present organization is the outcome of the legal dispositions enforced by the 1964 Water Act; an overall water quality inventory is to be performed every five years. Since 1972, "permanent sampling points", linking two successive inventories supported jointly by state subsidies and basin agencies, were monitored to provide data. However, this method was expensive and only little information was gathered. In 1987, the system was radically transformed, the result being the RNB. Most of the previous variables (constituents analyzed and environmental data) and sampling sites have been kept.

Presently, RNB is co-ordinated at the state level and operated at basin agency level. State co-ordination involves the following tasks: checking the application (in each basin) of the national rules, specific problems may, however, be addressed differently by the agencies, ensuring laboratory intercalibration and approval; cooperation with AFNOR (the French National Standardisation Body) for periodical improvement of analytical methods and standardization of new methods. Providing data on public requests at national level. For the last purpose, a specific organization, the RNDE (Réseau national des donnés sur éau: National water related network), is being developed.

Network and variables measured

The RNB 1994 programme covers 1,082 sampling sites, 946 of which are sampled yearly. The minimum annual sampling frequency permitted for these sites is eight samples per year. At each sampling site general physical and chemical variables such as pH, conductivity, organic pollution indicators, nutrients and specific ions are measured. At selected sites metals and organic micropollutants are measured.


No French national lake monitoring programme exists.

Table 3.5: French national surface water monitoring programmes.

No. Name Responsible institution Variables Period of operation &
Sampling Frequency (SF)
Data & reporting
Rivers and streams
R1 Inventory of the quality of running fresh waters RNB 47 physical & chemical variables since 1987
SF: min. 8/yr
1082 sampling sites
Database; RNB
Report; RNDE, RNB
Lakes and reservoirs
  No national network exists         No national data storage
Coastal and marine areas
M1 National sea water quality monitoring network - RNO RNO basic components, enzymatic activity, metals & pesticides since ?
SF: water; 2-12/yr biomass; 4/yr
sediment; every 2-5 yr
43 areas, each composed of several sampling sites Database; RNO annual reports;
M2 French seashore microbiological monitoring - REMI REMI faecal coliform, salmonellas   314 sampling sites in 88 areas database; REMI/REPHY
M3 French seashore phytoplankton monitoring - REPHY REPHY phytoplankton species composition, toxicity SF: twice a month, alert monitoring on a weekly basis 37 sampling sites;
alert programme 70-80 sites
database; REMI/REPHY

RNB: National Basin Network; RNO: National sea water quality monitoring network; IFREMER: Institut Francais de Recherche pour l'Exploitation de la Mer; REMI: French seashore microbiological monitoring; REPHY: French seashore phytoplankton monitoring. network.

Data storage and reporting

Each basin agency usually stores its own data. Standard reporting is examined by the RNDE. At the end of 1994, systematic reporting will include historic water quality data and detailed data synthesis for each sampling site.


Coastal and marine area

Three national networks, managed by IFREMER (Institut Francais de Recherche pour l'Exploitation de la Mer), are devoted to marine waters (M1-M3):

  • National sea water quality monitoring network, RNO (Réseau national d'obsevation de la qualité du milieu marin) (M1);
  • French seashore microbiological monitoring, REMI (Réseau de surveillance microbiologique du littoral francais) (2);
  • French seashore phytoplankton monitoring network, REPHY (Surveillance du phytoplankton du littoral francais) (3).

The objectives of the RNO (M1) is evaluation of the levels and tendencies of the overall variables describing sea water quality. IFREMER co-ordinates sampling and analyses performed by several local organizations. The RNO network consists of 43 sites, each composed of several stations. Sampling frequency varies between 2-12/yr and variables measured include general physical and chemical water quality variables, metals and pesticides.

The objectives of the REMI (M2) are evaluation of the levels and tendencies of microbiological contamination of the sea, mainly focused on shellfish. The programme consists of a survey network of 88 sites and 314 sampling points and an intervention network of 278 points. Faecal coliforms are measured at all sampling sites and Salmonella is measured at intervention sites.

REPHY (M3) is a long-term phytoplankton survey, and monitoring programme that is used during blooms of toxic algae, "red tides", etc. The programme consists of a survey network of 37 sampling sites and an alert network of 70 to 80 sampling sites. Sampling is undertaken twice a month with determination of phytoplankton species and shellfish toxicity assays.

Geographic coverage

Filed under:
European Environment Agency (EEA)
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