The Greater Hyderabad Municipal Corporation (GHMC) has commissioned a safety audit on its stormwater drains, with emphasis on the open drains, in preparation for the monsoons. About a year ago, a 10-year old girl got washed away in a stormwater drain at Kalasiguda in Secunderabad after slipping through the gap in the concrete slab covering the nala. In September last year, another four-year-old walked into an open manhole in Pragathi Nagar during heavy rains, and got swept away. His body was found in a lake nearby. Within a few weeks, another woman residing by a stormwater drain in Chilkalguda fell into it and died.
The safety audit is expected to help the civic body prevent similar incidents. Zone-wise tenders have been called for inviting agencies to submit their bids for the consultancy services for conduct of nala safety audit of the existing stormwater drains in the city. The third party agency needs to conduct the audit by designating teams to have a walk-through of the entire length of all nalas and drains in the zone and to ascertain safety of the existing drain network with an aim to reduce the adverse effects on people and property. Duration of the study is 90 days, ending with report submission.
The city has a stormwater drain length of 1,300 kilometres, 390 kilometres of this is covered by open drains.
“After the report, necessary repairs and rectifications will be taken up, and they need to carry the follow-up inspections and submit another report,” an official informed.
As part of the job, the agencies need to conduct a field survey of the drain network to ensure that they remain adequately protected, not to let any person fall into them during heavy rains, and not to allow public dump solid waste into the nala. They would check the open nalas for width and fencing, and the covered drains for any abrupt openings. With regard to the box drains, they would take a survey of damaged or missing catchpit covers and inspect if the covers level with the road.
They are also required to check if warning signs are provided along the nalas, identify vulnerable locations where there is scope for littering and dumping of solid waste, plastic waste and also construction debris leading to blockage of the drain.
Also to be identified are locations of erosion where roadside waste or dirt can get washed into the drains during rains, and where untreated sewage water or industrial waste is being let into the drains. Identifying strategies to prevent both the situations too is factored in as part of the task, besides carrying out rainfall data analysis, derivation of intensity-duration-frequency curves and deficiency analysis, as per the tender document.
It has become a common occurrence in city during heavy rains for people to die after falling unawares into the stormwater drains or catchpits, and getting washed away. The safety audit is being done on the city’s nalas for the past three years, in order to prevent untoward incidents resulting in fatalities.
