Hidden deep below the surface of the Chesapeake Bay and the Patapsco River, stretching from Annapolis to Fort McHenry, is an underwater highway for the world's largest ships. It is 50 feet deep, 700 feet wide and 25 miles long, 7carved like a giant trough into the soft ;bottom of mud, sand and clay.
People in the shipping business say that channel is a big reason the port of Baltimore survives. While the evolving demands of the maritime trade have left much of the port outdated and empty, Baltimore's channels are as deep and roomy as nearly any on the East Coast today.
But they are expensive.
As a debate brews in Washington over how to pay the $550 million annual bill for maintaining the nation's harbors, officials in Baltimore fear their port's competitiveness could be at stake.
President Clinton and others want shipowners to pay for harbor maintenance -- they use the channels, and it's their huge vessels that make them necessary.
But in a port like Baltimore -- one struggling to maintain its position as an outpost for international trade -- officials say attracting business is already hard enough. And they fear that any extra cost to the ships could be just enough to scare them away for good.
"It's pitting one port against another," said Frank Hamons, director of harbor development for the Maryland Port Administration. "It could create a major problem here."
While major port cities like Seattle and Long Beach, Calif., enjoy natural harbors as deep as 70 feet, the shipping areas of the Chesapeake are essentially man-made. Engineers have been digging out Baltimore's waterways for more than two centuries.
With horse-drawn plows in the 1700s, or cranes, barges and mile-long pipelines today, man has created an artificial bottom specifically to accommodate bigger and longer ships.
The first publicly financed dredging project in Baltimore is believed to have been an effort in the 1780s to deepen the Inner Harbor to 9 feet -- enough for deep-keeled sailing ships. Today, even with 50-foot-deep channels, ships hauling coal and iron ore can come perilously close to scraping the bottom.
Money is the reason for the deeper channels. Experts estimate that each extra foot of depth allows a ship to carry 2,000 extra tons of cargo. At 50 feet -- deeper than New York and as deep as Norfolk, Va. -- Baltimore remains a competitive option for the world's largest ships.
But the dredging never ends.
Few U.S. ports demand the level of maintenance that the port of Baltimore does. Silt-laden water from the Susquehanna River flows south and settles just outside the mouth of the Patapsco River -- where fresh water meets salt water, and where two of Baltimore's primary channels converge.
Storms and ships' propellers are forever stirring up mud from the channel's banks, which then collects at the bottom and reduces the depth.
The Craighill, Brewerton and Fort McHenry channels are the main driveways to the port of Baltimore. Engineers recently reduced their maintained width from 800 feet to 700 feet to save money, but keeping them clear is a priority.
Still, the port also relies on channels near the bay's mouth and a network running north to the Chesapeake and Delaware Canal, and all of them need to be kept clear.
The U.S. Army Corps of Engineers spends about $26 million every year to maintain Baltimore's channels at their authorized depths, dredging away silt that can build as much as 4 feet a year in some places.
The cost of "maintenance dredging" in Baltimore and every other U.S. port has been paid since 1986 by a Harbor Maintenance Tax on all cargo shipped through the ports.
But last year, the U.S. Supreme Court declared a portion of that tax unconstitutional, and the World Trade Organization is challenging the rest. Anticipating a shortfall, Congress is looking for alternatives.
A fee on every ship
Clinton would impose a fee on every ship sailing into U.S. ports -- a type of toll on the waterways. No ports would be immune, not even those that do not require dredging at all. The fee could raise as much as $980 million a year, and would be distributed, as now, to the ports that need it the most.
But officials in the maritime trades say the new fee would add additional costs to ports already close to pricing themselves out of competition. Foreign ports such as Halifax, Nova Scotia, and Vancouver, British Columbia, already profit from the higher fees and tougher regulations of their U.S. counterparts.
Shipping channels don't just benefit ships, they argue, they keep U.S. ports competitive and benefit every finished product and raw material moved through the largest trade nation in the world. As such, the taxpayers should pay to keep them in shape.
And they fear the fee might affect some cities more than others.
Ports that handle a lot of inexpensive, bulk commodities like coal and grain, for instance, could be hurt the most because ships hauling those goods already have thin profits.