As the southwest monsoon season draws to a close this month, this highly dynamic system leaves in its trail sharply contrasting impacts. Above-normal, if not copious, rainfall has resulted in brisk sowing in the kharif or summer season, higher reservoir levels, and adequate soil moisture for the coming winter season. But it has also entailed devastating flooding, landslides, and other disruptions, which have been most felt in north India. Due to the monsoon’s fury, the Punjab government has declared all 23 districts as flood-hit. In this vanguard agrarian state, 0.4 million hectares out of the 3.2 million hectares of crop area has been affected. Last month, Punjab received 1,272% excess rainfall in a single day. Himachal Pradesh, Uttarakhand, and Jammu and Kashmir have experienced serious flash floods and landslides resulting in a mounting death toll. Metropolitan India is woefully unprepared to cope with extreme rainfall. In Delhi, the swollen Yamuna has inundated several low-lying areas displacing around 14,000 of people. In Gurugram, there was severe water logging that brought the millennium city to a halt.
Why the rains turned extreme
It is no doubt true that extreme rainfall events have been rising every year while the number of rainy days is declining. But the scale of devastation in north India—which received three times its normal rainfall last fortnight—reflects the combined effect of western disturbances interacting with moisture-bearing easterlies from the Bay of Bengal and sometimes from the Arabian Sea. “When these two currents meet over the region, a lot of rain takes place,” according to Mrutyunjay Mohapatra, director general of the India Meteorological Department. Western disturbances refer to extra-tropical storms that form in the Mediterranean region and provide winter rains in the northwest of the Indian subcontinent. But their high frequency during the southwest monsoon season is “highly unusual”, felt Madhavan Nair Rajeevan, former secretary in the ministry of earth sciences, in an interaction with the media. There were as many as 21 cloudburst events—sudden localised extremely heavy downpour of rain—over the Himalayan states during the last two months that triggered severe flash flooding episodes.
The manmade factor and urgent fixes
While it is de rigueur to blame all of this on climate change—which is no doubt partly true—environmentalists believe that the devastation is also manmade. If there is deforestation and roads are being built in ecologically sensitive zones like the Himalayas, these developments loosen the topsoil and impact hillside stability triggering frequent rain-induced landslides. The devastation in the Himalayan states should definitely be a wake-up call for policymakers to cope with extreme rainfall by promoting sustainable development. The runaway pace of urbanisation has resulted in frenetic house and road building by encroaching upon lakes, ponds, and floodplains.
It takes only a drizzle to bring metros to their knees as stormwater drains are rarely de-silted in time and rainwater inundates roads and habitations. It took only 100 mm of rain to devastate the millennium city. When rainfall is incessant and reservoirs overflow, where will the discharged water go? For such reasons, flood-resilient infrastructure is the need of the moment. All the talk of smart cities can wait as metropolitan India needs to upgrade its drainage and rainwater harvesting facilities before the monsoon arrives. The lack of risk-proof spatial and urban planning that can check uncontrolled housing expansion on lake beds and wetlands needs to be addressed on a war-footing by policymakers.