Mumbai Metro 7A may lose Rs 250 crore if Airport Colony ramp and viaduct face demolition

The Mumbai Metropolitan Region Development Authority MMRDA which is constructing the Metro 7A corridor could face a potential loss of around Rs 250 crore due to issues related to the design and construction of the Airport Colony station ramp and viaductThe problem is linked to height restrictions imposed by the Airports Authority of India AAI as the Metro structure falls within the air funnel zone of Chhatrapati Shivaji Maharaj International Airport CSMIASources in the MMRDA told MidDay that the authority is still awaiting the AAIs response to its latest request for permission to increase the permissible height of the structure There are growing concerns that the Airport Colony station ramp and viaduct may have to be demolished if the required clearance is not granted potentially resulting in the loss of nearly Rs 250 crore already spent on constructionHeight restrictions pose challenge for Metro projectThe 342km Metro 7A corridor will connect Terminal 2 of CSMIA with the wider Metro network providing connectivity towards MiraBhayandar and South Mumbai through the underground Aqua LineJ Kumar Infraprojects is constructing the partly elevated and partly underground corridor while SYSTRACEGSMCIPL has been appointed as the General ConsultantEngineer for the administration of the contractAccording to news reports from November 2023 the MMRDA had approached the AAI for clearance to construct the Airport Colony station and ramp The AAI granted clearance on January 2 2024 but permitted a height that was 29 metres lower than what was required under the projects designConstruction affected by lower permitted heightThe restriction created a major challenge for the MMRDA as construction could not proceed according to the approved design and work had to be haltedThe MMRDA approached the AAI again on January 31 2024 seeking clearance for the viaduct between the Airport Colony station and the rampThe AAI issued a noobjection certificate on March 18 2024 but permitted the viaduct to have a height ranging from only 053 metres to 275 metres This was lower than the height required for the Metro system to operate safelyConsultant responsible for design coordinationAccording to MMRDA Director Metro Projects Basavaraj M B SYSTRACEGSMCIPL appointed as the General ConsultantEngineer for administration of the contract was responsible for coordinating the design and statutory requirements including aviationrelated height restrictionsldquoThe additional height required for the OHE system was not adequately highlighted and factored in by the Consultant at the appropriate stage of design and planningrdquo Basavaraj saidThe issue relates to the additional vertical clearance required for the overhead electrification system which was not sufficiently accounted for during the relevant stages of planning and design according to the MMRDAMMRDA awaits AAIs final technical confirmationThe MMRDA is presently pursuing the matter with the AAI and is awaiting its final technical report and confirmation regarding the applicable height clearances and any modifications that may be requiredThe authority has sought relaxation in the height restrictions for the entire structure maintaining that altering the height of the Metro line is not feasible because of engineering constraints Raising or lowering the structure it said would affect the gradient of the ramp and create further technical challengesldquoWith the AAIs final report awaited MMRDA will undertake a comprehensive technical assessment and take further course of action upon its receiptrdquo Basavaraj saidDemolition could put Rs 250 crore at riskWith the AAIs final clearance still awaited uncertainty remains over whether the existing ramp and viaduct can be retainedIf the required relaxation is not granted and the existing structures have to be demolished or substantially modified around Rs 250 crore already spent on their construction could be at risk