Medam is a database of the Marine Strategy Framework Directive (MSFD) monitoring program for the Mediterranean Sea, "Benthic Habitats and Seabed Integrity" component.
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The Medam website has been integrated into the European Sea Atlas of the European Commission.
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The Medam website has been updated significantly in 2016 and 2017.
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MEDAM is the sister website of MEDAMP, the observatory of the protection of biodiversity :
Any quotation or use of elements of this data management system should be mentioned as "MEDAM Université Côte d'Azur CNRS ECOSEAS"


Calculation of the surface area of shallow bottoms was based on the outline delimited:
 - on land, for sea level (0 m), by the line of the natural coastline (see particular cases in outline of original coastline)
 - at sea,
     + for the -10 m and -20 m isobaths , the marine charts of the Service Hydrographique et Océanographique de la Mer (SHOM) were digitalised,
     + for the delimitation of countries (France-Italy, France-Monaco and France-Spain) and the ECD water masses, the official limits were taken into account. On the other hand, for the delimitation between the regions Provence Alpes Côte d’Azur and Languedoc Roussillon, and all the counties and urban and rural districts (départements and communes), we have drawn artificial delimitations since these administrative subdivisions have no official extension in the sea (at sea, it is the public maritime domain of the State). The line adopted follows the administrative limits on land and is extended out to sea perpendicularly to the coast.

The maps used are of different scales: in each case we have used the most accurate maps (the largest scale available). In contrast to the linear measurements, the surface area measurements are less exposed to major variations depending on the scale and the geography of the coastline. Measurements are a little more precise on the largest scale maps for irregular coastlines.
Several particular cases, in particular related to redevelopments partly constructed on areas excavated on land, superimposed constructions and urban and district borders that overlap a reclamation site, are cited for each reclamation concerned in the descriptive note for each reclamation (in the ‘Comments’ section of each descriptive note).

The total surface area of the zone richest in marine biodiversity in the Mediterranean (between 0 and -20 m) extends:
 - for the whole of the French Mediterranean coast (not including Monaco or Berre), over 1688 km² (807.23 km² between 0 and -10 m and 880.46 km² between -10 m and -20 m),
 - for the coasts of Monaco, over 0.9 km² ( 0.57 km² between 0 and -10 m and 0,35 km² between -10 m and -20 m),
 - for the Etang de Berre, over 163 km² (162.07 km² between 0 and -10 m and 0.85 km² between -10 m and -20 m),
 - for the whole of the coasts included in MEDAM, over 1851 km² ( 969.87 km² between 0 and -10 m and 881.65 km² between -10 and -20 m).

Measurements were made on the SHOM maps digitalised using a scanner then geo-referenced with Arcgis 10.

The total surface area of the shallow bottoms richest in biodiversity (0 to -20 m) extends:
 - on the French continental coast (not including Monaco or Berre), over 1188 km² ( 554.18 km² between 0 and -10 m and 634.04 km² between -10 and -20 m),
 - on the coast of Corsica, over 499 km² (253.06 km² between 0 et -10 m and 246.47 km² between -10 m and -20 m),
 - on the coast of Provence-Alpes-Côte d’Azur (not including Monaco or Berre), over 669 km² (308.88 km² between 0 and -10 m and 359.45 km² between -10 m and -20 m),
 - on the coast of Languedoc-Roussillon, over 520 km² (245.30 km² between 0 and -10 m and 274.54 km² between -10 m and -20 m).
All these data show that the zone richest in biodiversity in the Mediterranean represents a very narrow strip along the French Mediterranean coast. It is in this linear marine oasis that the light enables the development of most of the under-sea plants (quantitatively and in number of species). It is upon this ‘oasis’ that the redeveloped areas have been reclaimed from the sea.
The data presented in MEDAM provides a basis for specifying the wide differences that may be observed according to the type of coast: the surface areas of shallow bottoms are considerably more extensive off alluvial coasts (sand) than off rocky coasts. For example, off the coast of Provence-Alpes-Côte d’Azur, there are more extensive shallow bottoms along the 108 km of coastline of the Rhône delta (from Martigues to Saintes-Maries-de-la-Mer), or 349.66 km² , than off the 745 km of mainly rocky coastline from Menton to Martigues (318.68 km²). Similarly, of the mainly sandy coastline of Languedoc-Roussillon, there are more extensive shallow bottoms (520 km² for 226 km of coastline) than around the whole coastline of Corsica (499 km² for 977 km of coastline).

The details of surface areas by county (département), urban and rural district (commune) or by ECD water mass, are available in the numerical data.



An image data base has been developed in order to present visually the changes in the coastline at the sites of reclamation redevelopment schemes.


1628 photographs are available at this site, with ongoing updating of the image bank. The photographs may be recent or more historical (views of the coast prior to reclamation have been sought). Some are photographs taken from the air others at ground level (sea or land).


The images made available are of low resolution. The photographers are cited and may in some cases be contacted by e-mail (list of photographers). Any new photos or similar documents are welcome: contact us to upload them ! (aims, procedure, conditions)


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Access the cartographical data base to view the contour lines of all the reclamations and the contours of all the bathymetric and administrative limits.


Access data on the characteristics, description, year of redevelopment, illustrations and localisation of each reclamation > 100 m².


Access the historical record data base: the construction of each structure or part of a structure has been dated. This data provides the basis for showing on bar charts the progression over time of reclamations and their impact on the basis of administrative units (country, region, county ( département), municipal and rural district (commune) or ECD water mass).


For all French Mediterranean coasts (excluding Monaco and the Etang de Berre) (see ‘details’ for noteworthy regional or more local particularities).

MEDAM Inventory :

Original coastline : 2 062 km (> see details)

Surface area of shallow water bottoms prior to any reclamation (> see details) :

Between 0 and -10 m : 80 723 ha soit 807 km²

Between -10 m and -20 m : 88 046 ha soit 880 km²

Between 0 and -20 m : 168 769 ha soit 1 688 km²
Between -20 and -50 m : 330 030 ha soit 3 300 km²


Number of reclamations (>100 m²) : 1 050 (> see details)


Coastline ‘artificialised’ by reclamation : 223.02 km (> see details)

Surface areas reclaimed by these redevelopments (> see details) :

Between 0 et -10 m : 4 226.13 ha

Between -10 m et -20 m : 903.70 ha

Between 0 et -20 m : 5 129.83 ha


MEDAM Impacts :

Rate of ‘artificialisation’ of coastline (linear) : 12.27 % (> see details)

Rate of irreversible destruction of shallow water bottoms by reclamation (> see details) :

Between 0 et -10 m : 5.24 % 

Between -10 m et -20 m : 1.03 % 

Between 0 et -20 m : 3.04 %


Progression :
A step in the right direction: a clear slowing down of reclamation from 1985  (> see details).