Puerto Rico is a self-governing Commonwealth in union with the United States. Both topographic and geological mapping have been undertaken by the United States Geological Survey (USGS) in association with the Puerto Rican government.
The modern topographic mapping forms part of the regular USGS program, although the basic scale used is 1:20,000 instead of the more usual 1:24,000 characteristic of most US states. The scale originally chosen was 1:30,000 and a complete series at this scale was published, but the 1:20,000 scale was adopted in the 1950s and only the sheets covering the islands of Culebra and Vieques are still at 1:30,000. The 64 sheets which cover the main island conform to the 7.5-minute quadrangle format of USGS mapping and are on a Polyconic projection, Clarke 1866 ellipsoid. The sheets are in three colors with 1 m, 5 m or 10 m contour intervals, and show municipal and barrio boundaries as well as the usual cultural detail. The first photogrammetrically produced 1:20,000 scale sheets were issued in 1957 and the series was completed in 1972. Subsequent photorevision of most sheets was carried out in 1982. Since 1988, the USGS has developed a geographical information system for Puerto Rico, and the 1:20,000 topographic maps have been digitized to form a basis for this system. Soil, geology, land use and ground water data have also been entered into the system.
Derived maps have been published by the USGS at scales of 1:120,000 and 1:240,000. They are in Spanish, and available in two-color base or five-color topographic versions. The later has contours at 50 m or 100 m according to scale, and there is also a shaded relief version of the 1:240,000 scale map.
Soviet military topographic mapping of Puerto Rico is available at the following scales: 1:1,000,000 (2 sheets, complete coverage, published 1963-1966); 1:500,000 (4 sheets, complete coverage, published in 1979) and 1:200,000 (7 sheets, complete coverage, published 1976-1983). These products are available in print, digital raster and digital vector GIS formats from East View Geospatial.
Nautical charts of the seas around Puerto Rico are published by the National Ocean Service (NOS) of the National Oceanic and Atmospheric Administration. Chart 25640 covers Puerto Rico and the Virgin Islands at a scale of 1:326,856, while a series of five 1:100,000 scale charts covers the islands in greater detail. A number of larger scale charts cover ports and their approaches.
Geological and other resource surveys were undertaken as early as the 1910s and 1920s as part of a scientific survey sponsored by the New York Academy of Sciences, the Puerto Rico Government and several other agencies. In 1952, the USGS began a project in cooperation with the Puerto Rican Industrial Development Corporation to assess the mineral resources of the island. This led to a detailed basic geological mapping program and the production of a 62-sheet, multi-color series at 1:20,000 scale. A digital 1:200,000 scale geological map of the whole island is in preparation.
A series of 1:40,000 scale marine geological maps of the Puerto Rico insular shelf has been issued since 1991. The mapping has been undertaken by the USGS in cooperation with the Puerto Rico Department of Natural and Environmental Resources in order to identify the potential sources of sand for the construction industry beach replenishment, and to understand better the movement of sediments between beaches and shelf. The maps show bathymetry as well as surficial geology.
Landslides are a common occurrence in the mountainous areas of the country and a general map of landslide hazard was published by the USGS in 1979. A more detailed study of areas prone to landslide was initiated by the USGS in 1987.
Soil survey of Puerto Rico began in 1928, but a soil map of the whole island was not published until 1942. Later the Soil Conservation Service of the United States Department of Agriculture published land capability and soil erosion maps and a number of more detailed soil maps. A new general soil map of the island was published in 1990 by the Natural Resource Conservation Service (NRCS) (formerly Soil Conservation Service). A State Soil Geographic (STATSGO) database for Puerto Rico has also been developed by NRCS and was published in 1994. STATSGO is a generalized database of soil-related data, with an input scale of 1:250,000 and a resolution of about 625 ha.
The International Institute of Tropical Forestry (IITF) of the US Department of Agriculture’s Forest Service is located at Río Piedras, and has undertaken or sponsored a number of land use mapping projects. The map of the Ecological life zones of Puerto Rico and the US Virgin Islands, published in 1973, is no longer available, but a new digital land cover map based on interpretation of 1977-8 air photographs has recently been produced as a contribution to the natural resources inventory program of the Puerto Rico Department of Natural and Environmental Resources. The data is in ARC/INFO format, and are used in combination with the USGS topographic database mentioned above. It is planned to further refine this map and to use recent SPOT imagery for analysis of land use changes since the 1977-8 period. Also sponsored by the IITF and published with an accompanying report by staff of the Institute is a set of six 1:20 000 scale maps of Land use and land cover Guanica Commonwealth Forest by L.L. Vélez Rodríguez interpreted from air photographs and depicting land cover in this biosphere reserve at intervals from 1936 to 1989. The report was published in 1996.
A map of the Caribbean National Forest, Puerto Rico 1:25,000 is published by the United States National Park Service (NPS) in their National Park and Recreation Series. There is a paucity of commercially produced maps, but general tourist and road maps are published by Karto+ Grafik, International Travel Maps (ITM) and Berndtson and Berndtson (B&B). The latter has street maps of San Juan and Ponce on the reverse.