Drained of ideas big cities need to upgrade water run off systems to account for new patterns of rainfall

Drained of ideas big cities need to upgrade water run off systems to account for new patterns of rainfall

It’s a familiar story every monsoon. A few hours of rainfall and our metros are inundated. This annual urban horror story is made worse by the fact that huge amounts of money are spent on desilting city drains every year. In fact, with Covid-related restrictions in place this year, there was hope that municipal corporations would be able to do a better job of preparing for rains. But in Delhi where monsoon showers arrived only on July 13 – delayed by around 16 days – streets, underpasses and busy intersections were flooded after a few spells of heavy rain. In Delhi multiple agencies – municipalities, PWD, irrigation – between them spend an impressive amount on desilting drains every year. But there’s little improvement in the flooding situation each monsoon.

A similar story unfolded in Mumbai. The Brihanmumbai Municipal Corporation claimed carrying out more than targeted desilting this year. But that boast was washed away with the first showers. BMC, the richest municipal body in the country, spends around Rs 70-100 crore every year just on cleaning drains. In Kolkata, waterlogging during the rains has become part and parcel of the city’s identity. Again, this isn’t for the want of funds – the Kolkata Municipal Corporation’s estimate of expenditure on sewerage and drainage for 2019-20 was Rs 273.58 crore.

Many blame unplanned urbanisation and construction on wetlands for water-logging. That’s true but it’s not a problem that can be fixed in a few months. Some improvement is possible by upgrading storm water drain designs. Current design standards take into account only one- or two-year flood levels. This must change so that drains can cater to greater volumes of run-off from heavier showers in short bursts. Plus, it makes sense to make urban storm water management a part of larger infrastructure development policies such as the Smart Cities mission. Leaving this only to municipalities, which often lack the institutional dynamism to take on new ideas, is clearly not working.