WASHINGTON (AP) _ Seeping water is damaging tracks, wiring and supports in parts of Washington's subway system, monopolizing the agency's time and resources to patch the problems.

The problem is most intense on the Metro's Red Line, from Farragut North station in the District of Columbia to the Medical Center station in suburban Maryland, a total of about nine miles of track. Washington's subway is one of the deepest in the world, and the entire system is at or below the water table.

The water is believed to have caused several shutdowns, with corroded insulators producing smoke, as well as a fire in another tunnel last month when a metal vent shaft fell onto the track, The Washington Post reported in Thursday's editions.

``It's crippling our power and communications systems and our track infrastructure at a rate that is way beyond anything we thought before,'' Metro General Manager Richard A. White told the Post. ``The tunnels look like the Luray Caverns,'' a cave formation in Virginia.

The water hasn't weakened the structural integrity yet, Metro officials said, but pools are forming from the constantly falling water and stalactites are forming from the tunnel ceiling.

The troubled section is the only set of tunnels without a waterproof liner. Newer tunnels have a vinyl lining that catches water and diverts it from the concrete walls. At the time the Red Line tunnel was built engineers thought dense concrete could resist the water, but micro-fractures have developed over time.

In the 1980s, Metro workers plugged about 500 water holes a year. Now, that figure has rocketed to a projected 4,500 this year. Every month, Metro pumps about 1.25 billion gallons of water from the subway tunnels.

``All we do is spot a hole, patch it, spot another hole and patch it,'' White told the Post.