BENGALURU: ‘Grow vertically’ is the state government’s call given to Bengaluru as there is a severe space crunch to expand horizontally. But while tall residential and commercial structures are coming up in the state capital, there appears to be no one keeping tabs on the city’s capacity to support skyscrapers — especially when seismic activities are becoming more frequent in the Deccan Plateau and skyscrapers require deeper digging to support their foundations.
Unfortunately, there is no data with any of the agencies on how many tall structures the city can support, nor on how many skyscrapers stand in Bengaluru. Neither Bangalore Development Authority (BDA) nor the Bruhat Bengaluru Mahanagara Palike (BBMP) have a list or a consolidated data on number of high-rise structures (residential and commercial) in the city.
BBMP Town Planning chief Sunil Kumar said they were giving permission based on BDA’s master plan and floor area ratio. “We do not have consolidated data on how many apartments and commercial spaces stand in Bengaluru,” he said.
The BDA officials in the meantime admitted that Bengaluru was still growing as per the 2015 master plan and there has been no evaluation of its growth till 2022.
This is also worrisome as seismic experts question the unregulated deep digging for laying foundation for high-rise structures. “So far, the Deccan Plateau is known to be the hardest and oldest rock formation. But with the recent incidents of earthquakes in various parts of Karnataka, and the rising tall structures and intense infrastructure projects being undertaken in Bengaluru, it is high time a detailed study is conducted,” said a seismologist and official from the Mines and Geology Department.
Citing the example of a 35-storey building in the city, the official explained, the foundation has to be at least 20 feet deep. The effects of such deep drilling needs to be assessed.
‘Groundwater table has also started to dip’
Experts and officials from the departments of Mines and Geology, Environment and Ground Water Board have demanded carrying capacity study.
Officials from the Ground Water Board said the groundwater table has also started to dip and permissions are being denied in many cases. “On an average groundwater table ranges from 15-25 metres. So, as a policy-decision we give permission for digging borewells for half the extraction quantity applicant is seeking permission for and also making it mandatory for double quantity rain water harvesting,” the official said.
Officials from the environment department pointed out that permission for high rise structures is taken on a piecemeal basis but the ground reality is completely different.
“The civic bodies have little or no control of the construction,” officials added. The authorities seem to have finally woken up, and have planned to take the space route to put things in order. “We have asked the Karnataka State Remote Sensing and Application Centre to prepare satellite and drone images of ground details at the cost of Rs 1.40 crore. This will be used for the 2041 master plan,” BDA town planning department, joint director, H V Sannapaiah said.