The national mapping agency in Thailand is the Royal Thai Survey Department (RTSD). It was founded in 1885 and is responsible for ground and aerial surveys, for the production of topographic and thematic maps, and for geodetic and geophysical surveys of the country. The first modern base mapping of the country was a 1,161-sheet 1:50,000 scale map, (Series L 708), produced in the 1950s under a joint mapping agreement with the United States, which was compiled using photogrammetric methods and covered all the country north of latitude 7° N. This map was recast as (Series L7117) from 1964 to give 772 quarter-degree sheets by 1973; 58 border sheets in other series have been added for complete coverage of Thailand in 830 sheets. This multi-color map is bilingual, uses the UTM projection and grid, Everest ellipsoid, and shows relief with 20 m contours. A continuous revision program is in operation, using aerial photographs and SPOT imagery, and since 1993 an automated mapping system has been used to capture 1:50,000 scale data, which allows faster map production and provides basic topographic data for national GIS development. Up to 100 sheets a year are being converted.
1:250,000 scale mapping was compiled between 1969 and 1973 as part of the Joint Operations Graphic (JOG) series, covering the country in 52 bilingual sheets. The civilian version of this map is (Series 1501S). Two other larger scales: a 1:25,000 scale base map (Series L 8019) was started in 1971, to cover development areas with 10 m contoured mapping, and about 350 sheets are maintained, while 1:12,500 scale coverage is compiled for areas around 160 primary and secondary administrative centers.
Soviet military topographic mapping of Thailand is available at the following scales: 1:1,000,000 (9 sheets, complete coverage, published 1960-1985); 1:500,000 (23 sheets, complete coverage, published 1964-1992); 1:200,000 (105 sheets, complete coverage, published 1963-1985); 1:100,000 (338 sheets, complete coverage, published 1968-1991) and a city (1:25,000) topographic map of Bangkok published in 1981. These products are available in print, digital raster and digital vector GIS formats from East View Geospatial.
Digital data has been captured from the 1:250,000 scale topographic map by the Environment Information Center (EIC) of the Thailand Environment Institute. These have been merged with data captured from other sources and reassembled as a national data set. The final version of data is now available as ARC/INFO coverage organized into nine layers (administrative, agricultural, environmental, forestry, geology, infrastructure, socio-economic, topography and water). These are distributed on CD-ROM and split into five regions.
The national hydrographic mapping agency is the Hydrographic Department Royal Thai Navy (HDRTN). Established in 1922, HDRTN is responsible for hydrographic and aeronautical charting of the country, including the maintenance of a range of 63 charts relating to the coasts and ports of Thailand.
The Department of Mineral Resources (DMRT) is responsible for official earth science mapping of Thailand. The country is covered with a full-color geological series published at 1:250,000 scale. Work on this map started in 1966 with German aid, and Bundesanstalt fϋr Geowissenschaften und Rohstoffe (BfGR) continues to contribute towards the geological mapping of Thailand. Following completion of 1:250,000 geological coverage some sheets are being revised and a new 1:250,000 scale map has been compiled and published on provincial sheet lines, to show carbonate resources in the country. From the mid-1990s emphasis has turned to the compilation and publication of a 1:50,000 scale series, on topographic sheet lines, with over 150 sheets now compiled. A fully automated production flowline has facilitated recent increases in the rate of production in this series. Other geological mapping includes geological and hydrogeological coverage at 1:1,000,000 and 1:500,000 scales, and at 1:2,500,000 scale a set of maps for 14 minerals and a geological map. 1:2,000,000 scale tectonic, mineral, Cainozoic sediments and basalt distribution mapping is published by BfGR in Geologisches Jahrbuch and issued with an English explanatory text.
The Thailand Remote Sensing Centre under the auspices of the National Research Council of Thailand is the national center for remote sensing activities, including participation with numerous map publishing agencies.
The Department of Land Development (DLD) is responsible for monitoring soil, land capability and land use. To support these activities it compiles 1:2,000 and 1:5,000 scale topographic coverage for farm planning, using 1:15,000 scale aerial coverage and a digital mapping system. DLD’s Soil Survey Division has carried out soil surveys of Thailand since 1963, and published reconnaissance level coverage of the whole country in 1:50,000 or 1:100,000 scale series using provincial sheet lines with a red overprint on monochrome RTSD base maps. Data was compiled from aerial coverage with ground interpretation and is being updated using SPOT satellite imagery. Smaller-scale derived soil mapping of Thailand includes a four-color printed 1:1,000,000 scale map using USDA soil taxonomy, as well as 1:2,000,000 mapping of the distribution of organic matter. 1:250,000 scale multi-colored maps of the distribution of saline soils have been derived from reconnaissance maps, LANDSAT imagery, earth science mapping, and published for northeastern Thailand. Applied soil mapping is also prepared, for example assessing land suitability for various plantation crops. The Land Capability Division of DLD produces a 1:250,000 scale land capability map for land use planning, most sheets being published in multi-color editions. 1:100,000 scale provincial land use maps are also compiled, and based upon interpretation of LANDSAT images and aerial photographs. Regional patterns of land cover are mapped in a 1:500,000 scale series derived from LANDSAT imagery.
The Royal Forest Department compiles land use and forest type maps. 1:250,000 scale forest boundary coverage of the whole country was derived by visual interpretation of LANDSAT imagery and digital image processing and is now being used to compile forest land use, cover and type maps of the most important areas. A 1:1,000,000 scale map of general forest types has also been revised from LANDSAT imagery. Detailed four-color forest mapping at 1:50,000 scale has been derived from 1:15,000 scale aerial coverage. Small-scale mapping of national parks is also published.
RTSD maintains and updates sheets in the loose-leaf bilingual National resources atlas of Thailand, which provides 51 small-scale thematic maps of the country. Other publications include a topographic atlas and road maps of Thailand.
Cadastral mapping is carried out by the Cadastral Surveying and Mapping Division of the Department of Lands. Urban areas are being mapped as 1:1,000 scale photomaps, with 1:4,000 scale photomap coverage of rural land parcels. An automated mapping system was instituted in 1990. The Agricultural Land Reform Office (ALRO) was established in 1975 and uses RTSD maps and aerial coverage for the planning and implementation of land reform. Several other official agencies produce large scale planimetric and topographic mapping of the country. The Royal Irrigation Department compiles large scale line maps and orthophoto maps of irrigation projects, the Electricity Generating Authority of Thailand also carries out its own large-scale topographic surveying to compile mapping of transmission line routes, while the Department of Energy Development and Promotion produces large-scale topographic and cadastral plans for energy resource development areas. The Bangkok Metropolitan Administration has completed 1:4,000 and 1:10,000 scale mapping of the City following photogrammetric survey in a cooperative project with the Japan International Cooperation Agency, and from 1992 has established 1:1,000 and 1:10,000 scale digital base mapping of the city, with Canadian and Australian technical support. Other digital urban coverage of the capital is compiled from aerial coverage by Loxley Intergraph, at scales up to 1:4,000.
Bangkok is the location for the headquarters for the South East Asian node of the GRID network (GRID Bangkok).
The Highway Department Club regularly revises a four-sheet 1:1,000,000 scale road map and many western commercial mapping agencies also publish general mapping of Thailand. These include HarperCollins, Macmillan, New Holland, International Travel Maps (ITM), and RV. Nelles Verlag, New Holland, and Berndtson and Berndtson (B&B) also issue indexed street maps of Bangkok. Periplus started a tourist series relating of popular areas in Thailand in the mid-1990s.