No proper outfall for drainage channels: DJB on Kirari flooding

Delhi Jal Board attributes waterlogging in Kirari to external factors, citing poor drainage infrastructure and DDA's landfill actions, not sewage system faults.

In a report to the National Green Tribunal (NGT), Delhi Jal Board (DJB) has defended itself over waterlogging and stagnating waste water in northwest Delhi’s Kirari, claiming they are a result of external factors, including the “obstruction of natural drainage channels” and “lack of stormwater management infrastructure” and not a result of any faults in the sewage system.

Decades of rapid, unplanned growth in Kirari have left over 100 unauthorised colonies with no proper sewerage or stormwater networks.

Decades of rapid, unplanned growth in Kirari have left over 100 unauthorised colonies with no proper sewerage or stormwater networks. The lone Kirari Suleman Nagar (KSN) drain handles only a fraction of required capacity, causing severe sewage overflow and knee-deep waterlogging during every monsoon. With media reports highlighting stagnant wastewater and waterlogging in Kirari — particularly Sharma Colony, the long-pending issue came under spotlight once again in January. NGT took suo motu cognisance of the reports and is currently hearing the case.

The report dated August 11, seen by HT, said that in areas such as Sharma Colony, DJB has already laid a sewage network in line with proper hydraulic design in the colony, but that it had not been operationalised in the absence of a trunk sewer to manage the area’s outflow.

A trunk sewer line is a large-diameter line that collects wastewater from smaller main and collector sewers. It acts as a primary artery in the underground network conveying high volumes of sewage.

It blamed the Delhi Development Authority (DDA) for filling the nearby low lying areas with waste and inert material from landfill sites without making any arrangement for the discharge. “The DJB sewage network is designed to handle the toilet waste,” it said.

The DDA had not responded to HT’s request for comment till the time of going to print.

In its response, DJB further said, “Waterlogging is not attributable to sewage accumulation but it is due to accumulation but it is due to stormwater mixed with surface run-off. Construction of drains falls under purview of I&FC (irrigation and flood control department) and DSIIDC, whereas operation and maintenance lies with MCD.”

The status report said the DDA is constructing big-sized drains for disposal of stormwater in the area.

Further, the trunk sewer line, being built by DJB, “upon completion shall facilitate the discharge of sewerage to the Pratap Vihar wastewater pumping station, which is 98% complete,” the report said. It added that the sewage from this site will be treated at the Rohini sector 25 sewage treatment plant (STP).

In a Union government-monitored initiative, six projects are being undertaken to mitigate flooding in the area, including the construction of side drains in colonies, a drain along the railway line, a DDA drain up to the Supplementary drain, KSN drain, and two drains along the Rohtak road.

“Due to absence of the above infrastructure stormwater was flowing in the nearby low lying areas...Low lying areas have been filled by the DDA without making arrangements for disposal of the discharge; thus it has resulted in the backflow, flooding and unhygienic condition,” the DJB said.