Monsoon has covered almost the entire nation and it has already started (as usual) playing havoc with human lives and property. Some of the cities like in Mumbai life has come to a standstill with many lives lost and properties destroyed. Many places in Mumbai city are inundated (including a site where municipal water treatment plant was located) by rain water, suburban train services stopped and road mobility disrupted. Soon heavy rains will be followed by water borne diseases, pothole filled roads and visibly shaken common man who is already disturbed by Covid-19 and prolonged lockdown.
Of course, such problems are not restricted to one city alone or some of the cities in India but are experienced elsewhere in the world too. According to European Environment Agency (EEA), increased flooding is likely to be one of the most serious effects from climate change in Europe over coming decades.
During heavy rain, cities may be flooded if the water cannot drain quickly into the ground and the sewage system in cities cannot cope with the amount of water. A growing city means urban area covered with more impervious surfaces such as buildings, concrete or asphalt, where the soil is ‘sealed’.
Some of the developed cities like Paris, Bucharest and Barcelona have more than three quarters of their surface area sealed, meaning that there may be a risk that water cannot disperse so quickly into the ground during heavy rainfall. Most of the Indian cities too will soon fall into this category unless our urban planning is suitably modified. However, it is important to be aware that soil sealing is only one factor contributing to increased risk of urban flooding.
Poor stormwater drainage system may also aggravate the situation. Extremely heavy rainfall which was seen recently in Mumbai can cause flooding as the sewers may not be able to cope with the huge volume of water.
Experts also have pointed out that global warming is causing multiple observed changes in the climate system like increases in both land and ocean temperatures, as well as more frequent heatwaves in most land regions. There is also view that the global warming has resulted in an increase in the frequency and duration of marine heatwaves. Scientists have also warned that short bursts of intense rainfall are likely to increase with global warming for Indian cities. With sub-daily precipitation extremes are increasing faster than daily extremes due to global warming we may have to live short spells of intense rains and its after effects.
Thus, though poor urban infra in Indian cities aggravate the situation caused by intensive rainfall, it’s the global warming which is the main reason for flooding. So, the solution to the problem doesn’t lie with the urban local bodies as the problem is global one. Therefore, it’s the case of cleaning the mirror when the dirt is on our face. Unless we find solution to the global warming there is no point in blaming the urban local bodies for the problem.