The Land, Infrastructure and Transport Ministry is planning to create a digital three-dimensional map of Japan for use in such fields as disaster preparedness and fostering new businesses.

Ministry sources said Sunday the estimated cost of the project, which would improve map accuracy, is 7.8 billion yen over three years. It is to start in the next fiscal year.

For the first year, the ministry will seek roughly 2.7 billion yen to enable it to gather topographical data using aircraft and lasers.

The map will be created at the Geographical Survey Institute by combining the data with satellite photos and a two-dimensional map.

A conventional topographical map with a scale of 1:25,000, for instance, can show 10-meter elevation changes at best. But a 3D version could show changes of less than 20 cm, the sources said.

Such detailed information would allow low-cost production of more accurate hazard maps for predicting possible damage from floods or tidal waves.

By including rain data, changes in river levels and the likelihood of flooding could be predicted more accurately. Laser-measurement technology would also allow better damage estimates by comparing maps before and after landslides.

The 3D map will eventually be made available for use by private-sector companies keen on developing new services, the sources said.

For example, it could be used in combination with future mobile phones that will transmit handsets' coordinates, they said.