Storm offers a host of challenges above ground and below - New York News | NYC Breaking News

Hurricane Sandy's powerful rain and winds present a slew of problems from the trains underground to the skyscrapers overhead. 

New York City has a bunch of features that threaten to make hurricanes an urban disaster: 

SUBWAY:

The NYC subway system carries 5 million riders on an average weekday and sits anywhere from one story to 180 feet underground. Pumps can clear 13 million to 15 million gallons of water out of the subway on an average day but there is a strong possibility they could be overwhelmed if a storm surge sent water pouring down subway entrances and sidewalk grates. For example, a 1992 winter storm that packed an 8-foot storm surge knocked out a commuter train line for 10 days. The city has sent workers to cover subway grates with plywood in Lower Manhattan to prevent flooding.   

Gov. Andrew Cuomo ordered the subway system to shut down at 7 p.m. Sunday; the Metropolitan Transportation Authority's buses and commuter rails also will be halted. The MTA was shut down 14 months ago during Hurricane Irene, for the first time for weather-related reasons.  

UNDERGROUND POWER:

Manhattan alone has some 21,000 miles of power lines beneath its streets. Con Edison has said most of the belowground equipment is sealed to protect it from flooding, but the utility said it was considering cutting power to 17,000 customers in Lower Manhattan if the surge is so severe it threatens underground lines since saltwater is more damaging to equipment if power is on.  

STEAM, WATER AND GAS:

Those lines are nestled in the 30 feet of ground below the power and telecommunications lines. However, cool water and hot steam pipes are a bad combination and Con Ed is considering shutting down the service -- used for hot water, heat and air conditioning. 

SEWER:

New York City carries sewage and storm runoff in the same pipes to treatment plants which is different from more modern wastewater systems. Even moderate storms often overwhelm the system and force officials to release untreated sewage into the city's waterways.

TALL BUILDINGS:

Most New York buildings are designed to handle the winds forecast from the coming storm, but there's always the possibility of loose debris breaking windows, Mayor Michael Bloomberg said. High-rise residents can also face the loss of elevator service and water if power goes out.