More than five years after it was recommended and after spending Rs 7 crore, the civic body has finally completed the first-ever base maps of the city.
But it can use the map only to improve the drainage system and prevent floods; the map cannot be used to help the Brihanmumbai Municipal Corporation (BMC) keep a check on illegal constructions, encroachments on its open spaces and for revision of the development plan, as originally planned.
A contour map, which is part of project, shows topographical elevations and depressions, and would be a great help in showing the city’s low-lying areas and predicting floods.
The reason: Mapping requires a go-ahead from the ministry of defence, and currently the BMC has permission to use the contour maps only for the city’s nullahs (drains that carry floodwater) and storm water drain system.
All areas that are under the defence ministry will be blacked out.
“As these maps can be a security risk, we will study only the nullahs inside the defence areas and black out everything else,” said Laxman S Vhatkar, chief engineer, storm water drain department.
“For the maps to be used for any other purpose, defence officials have told us that we will need to apply for fresh clearance,” he added.
The map was suggested by the state-appointed Chitale Commission after the July 26, 2005 deluge that claimed around 1,000 lives.
It is Mumbai’s first three-dimensional base map and has been made using state-of-the-art technology and aerial photography.
The BMC plans to use the map for this year’s monsoon preparations.
“We will also strengthen our flood-fighting efforts in low-lying areas in the map,” Vhatkar said. “We will then look at which areas need a stronger drainage system and pumping stations.”
Based on the contour maps, MWH consultancy, which is working on the project, will draw up a master plan for the city’s storm water drain system by the end of 2012.
The defence ministry’s spokespersons were unavailable for comment.