At 30 to 200 feet (9 to 60 meters) under the city things are a little
roomier and the items found get a whole lot bigger. The 63rd Street subway
tunnelNew Yorks most recent subway developmentis at
this level. Electric current is needed to run the subway system and to
light stations and work areas. Water and sewage lines service restrooms
and work areas. From the bedrock below much of Manhattan, large riser
shafts poke through to the upper reaches, delivering water from the
giant water tunnels below.