The Maryland Port Administration and the Chesapeake Bay Foundation have reached agreement on a plan to end the open Bay disposal of material dredged from Maryland’s portion of the Bay and its tributaries.

The agreement, resulting in legislation expected to clear the General Assembly, would allow material dredged from shipping channels to be used to restore wetlands or replace eroding islands, as well as be placed on land or in sites where they are contained.

But it would ban controversial open-water disposal except near Pooles Island, off Harford County, a site that has been used for years.

Even that site will be closed within a few years. Under the agreement, use of Poole’s Island must cease either when it has received its remaining 7.4 million cubic yards of capacity, or when the state completes a new 20-year plan for handling dredged sediment and identifies new disposal options.

At the latest, the use of Poole’s Island would have to cease by 2010.

“This is a historic partnership,”said Kate Philips, a spokeswoman for the port. “The most important thing is that this is going to ensure a new method for developing a 20-year dredge material placement program.”

Theresa Pierno, Maryland director for the Chesapeake Bay Foundation, said the agreement “is a huge victory for the environmental community.”

“It really establishes rules by which environmental and citizen input will be considered. I think we’ll be able to move more quickly in looking for other options” to open Bay dumping, she said.

Environmental groups have long criticized the open water placement of dredged material because it releases nutrients, stirs up sediments and smothers bottom habitat. The port administration has resisted ruling out open water placement because it is the most inexpensive method of dealing with the sediment.

Mike Morrill, Glendening’s communications director, said the governor fully supports the agreement. “The governor believes that you can have a strong economy and protect the environment,” Morrill said. “He is committed to doing both well.”

As part of the agreement, the state will establish an oversight committee made up of representatives of state agencies, the U.S. Army Corps of Engineers, the CBF and one or two citizen representatives.

“They are going to develop a strategic long-term management plan” for the disposal of dredged material, Philips said.

The plan will focus on alternative disposal methods, including restoring Bay islands, stabilizing eroding shorelines and creating or restoring wetlands.

The Maryland Port Administration and environmentalists have been at odds for years over the disposal of dredged materials. Port officials say that keeping shipping lanes clear is vital to the port of Baltimore and the 127,000 jobs linked to the shipping industry.

The state pursued a protracted effort to begin using a new open water dumping site above the Chesapeake Bay Bridge, but Glendening abandoned that proposal last summer in the face of strong opposition from a coalition of environmental and citizens’ groups and elected officials such as U.S. Rep. Wayne Gilchrest, whose Eastern Shore district would have been affected by the dumping project.

As a result of the agreement, the state will try a new approach to the vexing problem of disposing of huge quantities of mud — which can contain a wide range of chemical contaminants — while not harming the environment.

“We think that we’re blazing trails right now as far as facing this dual challenge and essentially beating it,” Phillips said.