Chennai’s Okkiyam Maduvu, a vital channel for draining floodwater from south Chennai areas like OMR, Velachery, Madipakkam, Adambakkam, and Pallikaranai, is set to undergo a significant restoration project. The state’s Water Resources Department has proposed a 27 crore plan to improve the channel’s capacity and prevent future flooding.
The project, funded by the Chennai Rivers Restoration Trust, involves several key measures. The department plans to construct a 450m-long retaining wall on the upstream side near Karapakkam bridge on OMR. This wall aims to prevent backflow or overflow of the channel, enhancing its carrying capacity. The department also intends to expand Okkiyam Maduvu’s width by 10m, further facilitating water flow. In addition, they plan to remove silt from the channel bed for a distance of 500m, aiming to increase the carrying capacity to 12,000 cusecs.
Okkiyam Maduvu, spanning 2.8km, currently carries water at a rate of 7,000 to 12,000 cusecs from the Pallikaranai marshland to the Buckingham Canal. However, the channel faced significant challenges during Cyclone Michaung in December 2023. Heavy tides prevented proper water drainage, while water hyacinths hindered free water flow.
Adding to the complexities of the restoration project, the Chennai Metro Rail (CMRL) has blocked four out of five vents in the channel and constructed a bund. These actions were taken as part of ongoing Metro Rail construction. While CMRL is expected to complete the pier work by the first week of September, the work is likely to extend into the monsoon season.
The Greater Chennai Corporation (GCC) has urged CMRL to remove the bund and clear the vents before August 31. Furthermore, Metrowater plans to expand the width of Okkiyam Maduvu from 80m to 200m, aiming for completion before the next monsoon.
WRD officials have recommended CMRL to build two additional vents to ensure smoother water flow. Water resources expert S Janakarajan highlights the neglect of Okkiyam Maduvu and emphasizes the need to remove solid waste and hyacinths to improve water flow.
The success of this restoration project will depend on collaboration between different government agencies and timely action. Addressing the challenges posed by ongoing Metro Rail construction and water hyacinth buildup will be crucial for ensuring effective flood control and mitigating potential risks in the future.
