Silt, sand, clay are problems dredged up in the effort to keep those ships moving


Here's one way to be optimistic about Maryland's looming crisis over where to put the considerable ooze dredged every year to keep the Chesapeake Bay navigable for shipping.

You could hold it all in a space the size of a football field.

Of course, you would have to stack it about half a mile high.

Or, it could be spread out, not much thicker than the butter on your toast; but that would mean annually slathering a slice of land a fifth the size of Maryland.

Neither solution is realistic, but then Maryland has never yet dealt with the full reality of maintaining a great economic heart like the Port of Baltimore.

It means not only dredging forever, but also finding ways to handle the dredged spoil without degrading the Chesapeake environment.

Until 50 years ago, a favored technique was to simply use the dredged silts, sands and clays to fill in Baltimore Harbor. This created lots of valuable commercial property.

But it also reduced three square miles of original wetlands to a dozen or so acres, ending the vast flights of bobolinks, or reedbirds, that fattened on the wild rice flats of the Middle Branch, and extinguishing the beds of wild celery where Audubon once painted canvasback ducks feeding.

Through the mid-1980s, dumping the dredged material back into the bay, or on upland sites near the water's edge, were the primary solutions. Both had undesirable side effects: smothering shellfish, squashing wetlands and spreading toxics, to name a few.

In 1984, after a decade of environmental controversy, the state opened a repository that promised a partial long-term solution -- a giant, diked holding area measuring two miles by a mile, created atop fast-eroding Hart and Miller islands off the eastern Baltimore County mainland.

Built at a cost of $60 million, Hart-Miller was supposed to entomb decades' worth of the most contaminated, hard-to-dispose-of sediments dredged from Baltimore Harbor.

It worked all too well. The dike also received millions of tons of uncontaminated material, much of it not even from the harbor. Some of the fill actually was of commercial sand-and-gravel quality.

Hart-Miller, even crammed well beyond its planned capacity, will be full within five or six years. Eventually it will be capped with good soils and made into a lovely state park.

But somewhere, the dredge spoil will continue to pile up.

That realization, coming a few years ago, sent the Maryland Port Administration in pursuit of approval to use the ultimate dumping ground: the Chesapeake's natural deep trough south of the Bay Bridges, a channel carved by the Susquehanna River during the last Ice Age.

Serious environmental concerns and more -- a sentiment that not even the Port of Baltimore's needs should begin to alter the fundamental shape of the estuary -- led to a law in 1990 banning any use of the deep trough. But the dredge spoil just kept coming.

If all this has made for a crisis in the short term, it just may force a new era in relations between port and bay. Consider this scenario, not yet a reality, but very much under consideration: Endangered bay islands, from the Chester River to the Maryland-Virginia line, being saved from death by erosion.

Dredge spoil stabilizes their shorelines, assuring prime nesting for thousands of birds. The spoil also creates thousands of acres of wetlands and protects threatened communities of watermen at places like Smith Island. One such project alone might use more than a year's worth of dredge spoil.

John Gill, a biologist, sees considerable merit in the islands approach. He says that a recent University of Maryland study examined bottom sediments and identified the "historic footprints" of several bay islands.

It showed that in the last century more than 10,000 acres, about 16 square miles of the islands, had eroded. And much of the eroded area is hard clay, not productive habitat for submerged grasses, crabs or fish -- in short, close to ideal for reclaiming with dredge spoil.

"I think we all agree, it's time to move some dirt," Mr. Gill says.

He doesn't work for the Maryland Port Administration or the Corps of Engineers, but for the U.S. Fish and Wildlife Service, an agency whose strict environmental mandate traditionally leads to routine objection to dredge spoil disposal.

"For years, we've been butting heads with MPA over [dredging], but we are trying to tell them now what to do instead of just what not to do," Mr. Gill says. His agency is one of more than a dozen state, federal and private organizations now part of a new MPA planning effort to devise environmentally beneficial ways to use the next 20 years' worth of material dredged from the bay's ship channels.

The effort is headed by Frank Hamons, an irrepressible soul who is head of harbor development for the Port Administration. "We will consider any proposal, from anyone," he says, and invites you to write him at 2310 Broening Highway 21224.

Other options include using spoil to build up the bay bottom to create oyster reefs and beds for planting submerged grasses; and mixing it with compost to sell as soil conditioner. Some scientists have suggested spraying dredge spoil on marshes that are losing out to rising sea level, on the theory that more sediment will enable the wetlands to build ahead of the sea's rise.

The largest obstacle to such plans, Mr. Hamons concedes, will be cost. Some environmentally beneficial uses may run as high as $10 per cubic yard of spoil, compared with about $1 a yard for dumping it overboard, and $2 to $3 for placing it in Hart-Miller. This differential can add up, since the state's dredging projections show more than 100 million cubic yards of spoil during the next 20 years. Transporting spoil down the bay for island reclamation even 30 miles from the harbor and its approach channels could add $6 a cubic yard to costs.

Curtis Bohlen, a wetlands scientist for the Chesapeake Bay Foundation, says he remains fearful that MPA will let costs skew what it defines as "beneficial use" of spoil.

But Mr. Hamons insists that the effort to devise such uses will not fizzle.

I hope he's right. On the other hand, a big new spoil-dumping area, in the ocean 16 miles off the bay's mouth, has received federal approval. This approach could look attractive to MPA if the crunch on disposal areas in the Chesapeake continues.

But ocean disposal of spoil is likely to be phased out eventually, as is happening with sewage sludge. So if Maryland relies on ocean dumping, another crisis over spoil surely will arise. It's only a matter of time.

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