CHENNAI: When the Greater Chennai Corporation embarked on a project to construct stormwater drains across the city in a record time of eight months as part of flood mitigation, little did the officials realise the challenge was bigger than what they had anticipated.
Officials said this is the first time an SWD project of this magnitude has been taken up in the last 10 years. TNIE looks at how things are progressing and can the residents escape waterlogging during the monsoon.
What corpn planned in May
Corporation officials were given a deceptively simple brief by the government before they started work in May — there must be no waterlogging in areas which faced the issue in 2021. The focus was on areas identified in the Thiruppugazh Committee Report and the 578 locations that were identified by the corporation as suffering from waterlogging every year.
“Under ordinary circumstances, this would have been a two-year project. The contract period should have been for a year at least but we are working with our contractors to finish work in eight to nine months,” said a senior corporation official.
Less time, bigger problems
To finish the work within the limited window and to keep it from affecting the quality of work, the civic body made a few decisions that were atypical of its usual approach. For one, instead of starting the drain work from the disposal point (where the water from the drains are released), the contractors were asked to cover stretches which were ‘free’, meaning stretches that were visibly free of trees, pillar boxes, places of worship or encroachments.
“This was different from the usual approach. In the case of starting work from the disposal points, it would be easier for the corporation to resume work with other contractors in case of premature closure of contracts. In this case, work was done in bits and pieces which means if there were four ‘free’ portions in a stretch, four teams would be working simultaneously,” said R Rama Rao, president of the Greater Chennai Corporation Contractors’ Association. From his experience of working with the corporation since 1977, he said this was the first time an SWD project of this proportion has been taken up.
To save time, the corporation utilised earthmovers in areas where they usually would prefer manual digging. The reason why manual digging is preferred is to ensure little or no damage to the underground utilities. However, since earthmovers were engaged there were instances of power cuts and damage to drinking water or sewage pipes. The corporation had instructed contractors to replace or repair damages.
Finally, workers had to work their way around perennial sewage. By their rough estimates, around 60% of the drains were choked by sewage. “In these cases, work took more time. We would keep 10-metre stretches dry at a time by temporarily stopping the sewage and carry out work in bits,” said a senior official.
Are we ready for the rains?
So far, around 160 km of drain work has been completed in core city areas. In the central regions (Teynampet, Alwarpet, KK Nagar, T Nagar, etc.) where a majority of the work is complete, residents can expect quicker drainage of water, according to officials.
“The time taken for water to drain will be much less in core city areas. Initially, we had identified some locations where it would take five days for the water to drain. It won’t be the case this time,” said a corporation official.
In the Northern and Southern parts of the city where work is still undergoing, pumps are to be put to use to supplement natural drainage. Apart from stormwater drains, the corporation is inspecting street lamp posts, tightening cables and pruning trees. It has instructed telecom companies to keep generators ready near mobile towers and telephone exchanges.
In addition, hospitals have been asked to keep generators on the first floor to avoid mishaps and for civil supplies to be ready with sufficient stocks of grains and pulses in case there is a need for mass cooking. Relief centres and GCC’s centralised kitchens are also prepared to handle an emergency, along with a control room to take calls and complaints.