NEW DELHI: The Indian Institute of Technology (IIT) Delhi on Wednesday presented its report on the causes of waterlogging and flooding in Delhi to Chief Minister Arvind Kejriwal. "All storm water drains should be maintained by a single agency," the institute recommended to the CM. Thereafter, CM directed the implementation of the report which identifies specific sewers and drains causing waterlogging and flooding.
The report on stormwater drainage infrastructure prepared by the Department of Civil Engineering, IIT Delhi, was commissioned by the Department of Irrigation and Flood Control. The report identifies the reasons behind clogging of specific sewers and drains.
"Majority of areas lying on the western side face frequent waterlogging problems, primarily due to shallow groundwater levels during pre and postmonsoon periods," noted the report. It also noted that the Trans Yamuna Region is protected from frequent flooding in river Yamuna by providing two marginal bunds. This also prevents any direct outfall into the river. Relief Drain is the only drain which is having the outfall in the river. Majority of drains flow from west to east (from the Yamuna River to the eastern side of the basin) against the natural flow direction. The water from the North Eastern basin gets collected into the G.T. Road drain.
The report recommended that storm drains should be treated as key public assets and no encroachment should be allowed. Any encroachment of the drain should be immediately removed and reported back. The department managing the storm drain should be made responsible for keeping the drain encroachment-free. Special drives to remove encroachments from the storm drains should be taken up. "No natural or artificial storm drain should be allowed to carry any sewage. Only treated sewage of acceptable quality as per CPWD norms should be allowed in the storm drains. All drains that are entering into NCT of Delhi (from Haryana, UP, etc) should be only carrying stormwater and treated sewage of acceptable quality as per CPCB norms," the report noted.
It also observed that no silt from the road (before or after road sweeping, manual or otherwise) should be allowed to be dumped into bell-mouths/drains. Road sweeping process should be completely overhauled. Weight/volume of silt received after street sweeping should be recorded. Segments of the road from where more silt is being received should be reviewed and the reason of the same ascertained. If need be, possible afforestation exercise should be taken up to reduce silt on the road segment.