AUGUSTA (AP) – Maine officials are seeking federal approval to designate Casco Bay the state’s first no-discharge area that would make it illegal for boats and ships to dump their waste in the bay.

Gov. John Baldacci announced Monday that the state has requested the designation from the Environmental Protection Agency to eliminate waste discharges from the thousands of commercial and recreational vessels that use Casco Bay each year.

It could take the EPA up to six month to review the proposal, officials said.

“As one of the most productive and heavily used bays in Maine, Casco Bay warrants the best protection we can provide,” Baldacci said.

There are 19 pumpout stations in Casco Bay where boaters can dispose of their onboard waste, but it’s not illegal for boats to dump their waste overboard.

Casco Bay includes the port of Portland and more than 20 harbors. The proposal would also extend the no-discharge designation up the Fore, Presumpscot, Royal, Cousins, Harraseeket and New Meadows rivers.

The bay includes more than 229 square miles of marine habitat and 197,000 acres of shellfish harvesting beds. It also has the largest concentration off eelgrass in New England, which serves as an important habitat for commercial fish species.

“We cannot stand by and let preventable pollution threaten these resources,” the governor said.

Baldacci has also directed the Maine Department of Environmental Protection to make sure all remaining “straight pipes” – pipes that carry untreated sewage from homes into the bay – are disconnected. Straight pipes have been tolerated in the past under special circumstances on some islands, but are now illegal.

Baldacci said his goal is to open 5,000 additional acres to shellfish harvesting in the next five years.