The Global Lakes and Wetlands Database was developed through a partnership among WWF, the Center for Environmental Systems Research, and University of Kassel, Germany. It draws upon the best available maps, data and information to display lakes and wetlands on a global scale (1:1 to 1:3 million resolution). The application of GIS functionality enables the generation of a database which focuses in three coordinated levels on (1) large lakes and reservoirs, (2) smaller water bodies, and (3) wetlands.
Level 3 (GLWD-3) comprises lakes, reservoirs, rivers and different wetland types in the form of a global raster map at 30-second resolution. For GLWD-3, the polygons of GLWD-1 and GLWD-2 were combined with additional information on the maximum extents and types of wetlands. Class ‘lake’ in both GLWD-2 and GLWD-3 also includes man-made reservoirs, as only the largest reservoirs have been distinguished from natural lakes.
The data is available for free download (for non-commercial scientific, conservation and educational purposes).