walk into New York City’s famed Grand Central Terminal and you see its iconic main Concourse with its beautiful turquoise ceiling the station serves Metron North Railroad which links the city to its northern suburbs but commuters and tourists don’t see most of grand Central’s internal structures its underground train shed the Park Avenue tunnel and the Park Avenue Viaduct they bring Metro North trains into the station but they’re more than a hundred years old and in dire need of Renovations and safety up Ates over the decades water salt and chemicals have eaten away at the structures creating deficiencies and over time the train shed won’t be able to support Park Avenue and the side streets above it if they’re not repaired more than 200,000 passengers on 750 trains come through the station on a typical weekday that’s about 98% of metronor service but officials say that service could be disrupted or even suspended if the train check the rail tunnel and the viaduct were to fail the MTA has started to repair this critical infrastructure and it will cost about 3 billion to rebuild and renovate these structures the work is a critical part of the mta’s next 5-year Capital plan