Centre asks CMRL for details of safety measures while tunnelling

CHENNAI: With the Chennai Metro Rail Limited (CMRL) to tunnel more than 1.2 kilometers in coastal regulation zone for Madhavaram Milk Colony to SIPCOT corridor, the Ministry of Environment, Forest and Climate Change has asked the Chennai Metro Rail Limited (CMRL) to submit details of safety measures in case likely collapse of soil in adjacent areas due to impact of tunnelling.

Apart from the details about safety measures, the environmental appraisal committee directed the CMRL to provide details of flood mitigation measures at entry and exit of Metro stations and evacuation shaft, and noise and vibration management plan during construction of the project. Seeking the details, the committee deferred providing clearance.

As per a document, Metro rail has plans to connect Madhavaram and SIPCOT under Phase-2 and Corridor 3 of the project. The corridor is the longest Metro rail corridor with a total length of 45.8 kilometers.

A total of 1,219 metres and part of Thirumayilai and Taramani stations, a culvert and evacuation shaft fall under coastal regulation zone.

As the project requires CRZ clearance, the State Coastal Zone Management authority has recommended the project for CRZ clearance in August based on which the committee is studying the proposal.

Madhavaram to SIPCOT corridor will have 50 station of which 30 would be underground stations.

In its application, CMRL stated that it is estimated 12.6 million would travel by public transport with the estimated 20.8 million daily person trips in 2026 in Chennai.

Tunnel alignment is proposed after the investigation of existing underground utilities as part of pre-planning, tunneling will be done using Tunnel Boring Machine (TBM), underground (UG) stations will be built by cut and cover method, UG stations are proposed with three levels such as platform level, concourse level, road level.

Based on the details to be provided by the Metrorail, the committee will make a decision on according clearance.