Saturday, 04 February 2023 | PNS | DEHRADUN
The Information Technology Development Agency (ITDA) has done a comprehensive drone survey of the Joshimath city affected by alarming levels of land subsidence. A high resolution contour map of the Joshimath region with a contour interval of two meters has been made in the survey done by drones. The map would now serve as a base map for mapping of geological features on a 1: 5000 scale which would help in preparing a proper geological model of Joshimath city and nearby areas.
The Geological Survey of India (GSI) demanded a large-scale contour map of the Joshimath area to prepare its own maps depicting the local geology and geological features. A team of the GSI is deployed in Joshimath which is collecting samples and data from the subsidence-affected areas of the city. The agency demanded a high-resolution contour map of the area to plot its data on them. On the demand of the GSI, the Uttarakhand State Disaster Management Authority (USDMA) sought the required information from the ITDA. In a letter to the director of ITDA, the additional chief executive officer of USDMA, Savin Bansal requested that the agency should prepare a high-resolution map of the Joshimath region with a two-meter contour interval. The USDMA told the ITDA that the contour map should filter out the houses and trees.
The director of ITDA Nitika Khandelwal told The Pioneer that the department deployed a team of seven experts who used two drones to conduct the required survey of Joshimath area. She said that the map has been provided to the SDMA.
A contour map shows the topography of an area and it depicts the contours which are lines joining points of equal elevation. A high-resolution contour map with a spacing of two metres would help in preparing a terrain model of the area and in it, the position of the micro-features including cracks on the ground is also clearly visible.
