The Agricultural Drainage Database (“BD Drainage”), the result of two years of collaboration, is a new interactive mapping tool for drained plots and drainage systems that improves knowledge of ground infiltration patterns and water flow systems at the plot and/or watershed level.
13 December 2019
The Drainage Database on the Seine-Normandy SIGES

Dissemination and consultation of the Drainage Database on the Seine-Normandy SIGES: example of a map showing the upstream routes of the drained water flow.


The need

In the second half of the 20th century, in order to boost agricultural yields, local and regional authorities and the State generously subsidised drainage constructions, which can have both qualitative and quantitative impacts on surface water and groundwater. However, data related to agricultural drainage are now jeopardised (lost or damaged archives, uncertainty about locations, etc.). It is therefore necessary to preserve this knowledge by giving it a new lease of life in digital form, which would also make it easier to exploit through the use of information technologies.

Consultation sheet for a drained area

Consultation sheet for a drained area.


The results

In the first phase of the project, the archives for the Eure and Seine-Maritime départements were identified and a model was developed to exploit the digitised data. The second phase, which began in 2016, focused on implementation. The system (from data entry to information dissemination) set up under this project is as follows:

  • Data entry  website
  • Data storage in a PostgreSQL database hosted at BRGM,
  • Data dissemination  website, in the Agricultural Drainage section.

The consultation and data entry websites were launched in 2017. In order to add value to the data, innovative features have also been developed. For example, by creating connections between specialist applications, it is possible to determine the direction of flow of drained water from agricultural plots to the points where they are discharged into the natural environment.

Using the results

Since February 2017, the SIGES Seine-Normandie has made online consultation available to everyone. Map layers, services showing upstream and downstream paths and more detailed technical data sheets all enable the public to access the knowledge contained in the database and to exploit its different characteristics. The enrichment of the drainage database with related services makes it a real decision-making tool in terms of water and risk management and resource protection for local authorities and engineering design firms.

The partners

  • Seine Normandy Water Agency
  • Eure Departmental Council
  • Seine-Maritime Departmental Council
The Seine Estuary and its marshes

Our partnership with BRGM enabled us to create a database in which we have compiled the data archived since the 1970s. We make them available to water managers who can themselves add to them with their own research results on drainage. This tool is of use to local and regional authorities for water conservation, risk management and also for knowledge of the agricultural landscape.

Jérôme Ledun, AREAS association

BD Drainage: drained agricultural plots, where does the rainwater go?

The BD Drainage collaborative database provides information on the path taken by water from agricultural plots that have been drained, through to its discharge into the natural environment, watercourses or groundwater. This video explains the process involved in setting up this database and its possible applications.