Some of New York's busiest subway stations flooded after a rainstorm, and commuters were furious

• Rain on Thursday plagued the evening commute for millions of New York City straphangers.
• Floodwater inundated many stations, including Grand Central, causing train delays.
• For decades, the MTA let drains clog with debris and is only now beginning to undo the mess.
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For decades, New York's Metropolitan Transportation Authority let sludge build up in thousands of storm drains throughout the city's more than 600-mile subway system.

Despite recent efforts to clean out the buildup, the clogged drains were on full display on Thursday as a rainstorm crippled massive chunks of rush-hour subway service.

"Trains are bypassing Grand Central 42-st in both directions because water from heavy rainfall is leaking into the station," read one service alert during the evening commute on Thursday.

Leaking appeared to be a bit of an understatement. In the mezzanine above the busiest transit line in North America, buckets did little to catch a deluge of rainwater pouring into the station, one of the most crowded in the entire system.

A little while later, Andy Byford, head of New York City Transit for the state-run agency, showed up to help employees try to clean up the mess.

But at other stations across the city, commuters delicately worked their way over - and through - some deep and disgusting puddles.

In Brooklyn, a certifiable waterfall drenched most of a station platform.