Cost of rapid urbanisation: Inundation
The First week of December 2015 was something out of a science fiction movie for the people of Chennai. Horrifying images were beamed across the globe as the country woke up to the devastating after-effects of rapid urbanisation without a plan. For people who lived through that week from hell, images and videos from Mumbai over the last 48 hours were familiar, to say the least.
India’s bustling financial capital turned into a poor man’s Venice as the last vestiges of the South West monsoon attacked the coast of Mumbai with all its fury. Depressingly, Mumbai’s example is not the outlier, it is very much the norm.
Take Bengaluru for instance. India’s IT capital may have developed into a Tier-I city but the effects have already handicapped it. So far this year, it has witnessed flooding three times. Encroachment of storm water drains (SWDs) is the primary reason for this seasonal recurrence.
Within the core of the urban agglomeration of Bengaluru, there are only 633 SWDs in a network spanning 842 km. Of these primary drains account for 142 km of the network, and secondary drains 426 km. Bengaluru’s drainage system can cope with 80 mm of rain. But due to encroachment and lack of maintenance, that capacity has diminished to 35-40 mm of rain. If it rains continuously for half an hour, flooding is inevitable.
In July 2016, BBMP officials had a given list of 1953 SWD encroachments, of which 1255 have been cleared. The remaining 728 encroachments are yet to be cleared. “We had sought deputation of land surveyors to mark the encroachments following which we will remove them but it hasn’t been done yet,’’ said a senior BBMP official.
Bhubaneswar is feeling the same effects. With a topography that slopes from west to east, Bhubaneswar was once known to have a natural run-off system that evacuated storm water within 20 minutes of a heavy shower. Some 30 years ago, the city had its natural drainage channels intact. Now, Odisha’s capital, spread over 186 sq km, is a concrete jungle. All its natural drainage systems have been encroached upon by high-rises.
The Bhubaneswar Development Authority, the urban planning body, closed its eyes to zoning regulations being violated. As the city burst at its seams, pressure on urban infrastructure grew. The Works Department and National Highway Authority of India went on a road expansion spree without bothering about basic engineering to facilitate drainage of water. The Bhubaneswar Municipal Corporation built more arterial roads while the old drainage system remained inadequate. A familiar tale.
