What is a Base Map ?
A base map is a map which shows the existing physical pattern of the land upon which survey info analysis or planning proposal can be superimposed. The information required for base map varies from map to map because it largely depends upon its scale, the area covered and the level of planning details.
Details to be shown on different level of base map:
For different levels of maps, information in base map is different which can be further seen in the following:
- For regional level base mao:
- Boundary: The boundaries that can be shown at this level are National Boundary, state boundaries, district boundaries, taluka boundaries, tehshil boundaries and village boundaries.
- Road: National highway, state highway, major district roads, other district roads and fair weather roads. The railway lines – broad gauge and meter gauge lines, bridges are also to be included.
- Topography: The major forestland, major hilly areas, rivers and streams, lakes, swamps, marshy lands etc.
- Settlements: The urban settlements, rural settlements and important head quarters.
- Contours: The contour interval in the base map at the regional level is 100m.
- Planning and administrative boundaries: planning area boundary (if identified), metropolitan boundary, urban area boundary, municipal corporation boundaries and zonal boundaries, census ward, administrative sub-division limits (if any), urban village or rural settlement within the municipal limits or on the fringe of the municipal boundary, cantonment area boundary (if any), grids (artificial or latitudes and longitudes).
- Roads: national highways, state highways, major district roads, arterial road, sub arterial road, collector roads, and local roads.
- Topography: Hills, water bodies, Rivers and streams, canals, lakes, swamps, marshy lands etc.
- Religious places: Religious places such as temples, mosques, churches, and tombs are shown.
- Contours: The contour interval shown in the base map at this level generally ranges between 3m to 5m depending upon physiography of town and scale of map.
- Apart from these, all major places of archeological interests, public and semi-public building (important landmark), major agricultural and city forest, district parks, gardens, green belts, floodable areas, Utilities and services lines are also shown in the base map at this level.
- The site planning level base map:
- All accesses to the site,
- Vegetations such as trees, bushes, etc
- Water bodies
- High tension lines, overhead electric lines, water supply lines including hydrants, sluice valve, sewer lines including man-holes, vent pipes etc with slope diameter of lines.
- Already existing features like well, brick kilns, quarries etc
- Contours are drawn at an interval of 500mm.