The National Green Tribunal has directed agencies constructing the Chennai Peripheral Ring Road in Tiruvallur to ensure that work over Kannigaiper Lake does not obstruct, divert or impede the natural flow of water. The order comes after concerns that a 280-metre section of the road could affect lake storage and increase flooding risks for nearly 50 villages on the western side.
The southern bench of the Tribunal said all design and execution work must comply with technical and safety standards, departmental clearances and the recommendations of Tamil Nadu’s Water Resources Department. The case was taken up suo motu in 2025 after a letter petition raised concerns about the impact of the road project on the lake’s water flow.
The disputed section of the Chennai Peripheral Ring Road comprises two components, according to a report submitted by the Tamil Nadu Road Infrastructure Development Company. These include a 100-metre high-level structure and an embankment covering the remaining 180 metres.
The Water Resources Department had issued a no-objection certificate for the high-level structure. However, it had not sanctioned the embankment and had recommended a separate structure for that portion to prevent any obstruction to the movement of water.
The petitioners had alleged that the department issued the no-objection certificate without adequately assessing the project’s impact. The Tribunal’s order records that the road section passing over Kannigaiper Lake could obstruct the natural flow of water, reduce storage capacity and create a flooding risk for settlements located west of the lake.
Following the concerns raised by the department, the Tamil Nadu Road Infrastructure Development Company examined the feasibility of constructing an additional structure for the embankment. The proposal submitted before the Tribunal provides for a 25-metre span between each pier.
The Tribunal said the proposed spacing would provide adequate clearance for uninterrupted water flow. The bench comprising Justice Pushpa Sathyanarayana and Prashant Gargava disposed of the petition while directing the agencies involved to follow the applicable technical requirements and the Water Resources Department’s recommendations.
The order places the water-flow design of the road section at the centre of the project’s implementation. It also distinguishes between the portion for which the department had issued an approval and the embankment component, for which a separate structural solution had been suggested.
The Chennai Peripheral Ring Road is a major road infrastructure project involving construction across the Tiruvallur region. The Tribunal’s directions mean that the concerned agencies must proceed with the lake-crossing works without compromising the movement and storage of water in Kannigaiper Lake. The proposed pier spacing and the implementation of the recommended structure will determine whether the 280-metre section meets that requirement.
