Feb 26, 2024
Feb 26, 2024
A second 'cyclone' has just given Tamil Nadu a miss. It was a close shave and had promised to give Chennai an avoidable third drubbing of the season.
Winter rains are not a novelty in this part of India. The Northeast monsoon has been an annual visitor since Time Immemorial. Then why this sudden emergence of a Chennai city drowning in rain waters, prompting the former BJP president Venkiah Naidu to demand that all the rivers and rivulets in the city be dredged as a long term measure.
Would dredging save Chennai? Except in the short term? These rivers and rivulets have been there for a long long time too. The sudden emergency of the 'flood-in' fate of Chennai reminds one of the floods that wrecked havoc in Mumbai earlier this year; they are also reminiscent of the now recurring annual floods that visit western Ahmedabad.
Both sides of the celebrated S G Highway turn into enormous water bodies dotted by marooned residents during the monsoon. The phenomenon is a novelty as western Ahmedabad was not ever flooded, once upon a time. It is so now. And it is on the basis of Ahmedabad's experience that one is tempted to draw the conclusion: that these floods are more man made than Nature's, as the quantum of the downpour has not really increased to justify the extent of the flooding.
That part of the city has seen unprecedented rush of construction of high and low rise buildings, bungalows, row houses etc accompanying the residential edifices are complementary commercial ones, shopping plazas, multiplexes, plus of course, the concomitant quota of paved roads.
While planning the main and arterial roads, how much attention is ever paid to the natural flow of water and extra efforts made to ensure that those natural passages are not blocked? Who ever thought of that?
So it comes about that the natural flow of the monsoon downpours no longer have their traditional outlets. Fields have been given over to concrete mazes, water bodies filled over and even where there is a natural flow, its path is interrupted by pucca roads: spanking new highways and autobahns which are the pride of the place.
Nobody links them to the overflowing of the canals which are themselves broken down cesspools plugged with garbage and waste, quite incapable of containing their own natural inflow, leave alone the extras generated by the highways closing off other flows.
Now if this can cause major havoc in a city like Ahmedabad, why not in metropolis like Mumbai and Chennai?
In both these cities, the pace of construction is much more frenzied and extensive. Chennai is a growing industrial hub that requires not that much more housing for its extensive work force. And the demands of modern work forces also include 'necessities' such as cultural centers, clubs, shopping malls, go-karting and bowling alleys etc. all of which make for solid concretized grounds which do not allow for the soaking in of rain waters in substantial enough quantum to prevent flooding out; while the roads and highways come in the way of the natural flows.
Mumbai has been expanding at a frenetic pace, its saltpans and marshlands swallowed up in construction accompanied by access roads and all the modern wizardry of communications.
Ditto Chennai that is set to become a leader amongst the developed and industrialized states of India. The country needs to move ahead. Which means coping with the problems which crop up in the steady march towards 'development'. So perhaps the way out would have to be a dramatic upsurge in drainage facilities design to cope with the sheet flows of the monsoon and cyclic storms.
How Ancient India Coped?
The wisdom of our hoary traditions was the conservation of sheet flows of rainwater in any and every way possible. Way back in the sixteenth century, India harnessed upto 60% of its precipitation, despite the fact that most of the annual rains came in bursts. These have been variously estimated at an average of 300 hours or twelve and half days in a year.
Of the 300 hours, half comes in less than 30 hours. In places like Jaisalmer, Bangalore or Bombay, 100 cms of rain come within 30 hours, spread over a rainy season of 100 days.
The genius of Ancient India dictated that water be stored wherever it rained, ' i.e. in hundreds of thousands of reservoirs, all over the countryside, known by different names in different parts of the country.
The sheer variety of names given to the water storage units reveals how widespread the practice was throughout the different parts of the country:
The eri, the kulam, the jheel, thesagar, the johard, the talab, thesar, the nadi, the khadin, thekund, the kunta, the katta, thepukur, the bandh, the ahar, even irrigated fields such as paddy, surrounded by bunds, which allowed percolation, built up soil moisture, reduced soil/land erosion and maintained atmospheric humidity.
Besides, there were also sub-surface tanks, deep step-wells in the urban areas and roof water harvesting, in which rain water was piped down to basement reservoirs or sub-surface tanks, to provide drinking water throughout the year ... the modern day version of which may just be the new found interest in percolation wells in commercial complexes and public places like gardens.
More by : Kusum Choppra