A new obstacle emerged yesterday in the epic battle over whether to dredge the Delaware River shipping channel, deepening it to 45 feet from 40, even as the project seems about to begin.

Delaware environmental officials denied a permit the Army Corps of Engineers was seeking. It had applied for permission in 2001.

Critics of the dredging characterized the denial as a major stumbling block, but supporters said the Army Corps of Engineers, a federal agency, could proceed without Delaware's approval for the project. The dredging could create 13,000 jobs by keeping Delaware River ports competitive with others on the East Coast.

The project also could generate millions of dollars in new investment in the region, supporters say.

"We don't view this as a deal-killer," said a source inside the Philadelphia Regional Port Authority, the Pennsylvania sponsor of the project, who agreed to speak on background.

In fact, initial bids for the $379 million dredging project, which has been planned - and fought - for more than a decade, are being considered by potential contractors.

In a statement yesterday evening, the Philadelphia Regional Port Authority said: "We are disappointed to learn of Delaware's decision on the permit application for the necessary deepening of the Delaware River."

The authority said it remained committed to the project and to working out the problems with New Jersey, Delaware, and the Army Corps.

The project would create a 102-mile-long, 45-foot-deep channel, from Camden's Beckett Street Terminal to the Atlantic Ocean.

Gov. Rendell has been a strong supporter for years and has said it would be good for the Philadelphia and regional economies.

Opponents have said that dredging could stir up toxic sediment that would pollute the river and hurt aquatic life. They also worry that the dredged material would be dumped in environmentally sensitive areas. They say the project is not economically necessary and would largely benefit only the riverfront chemical companies and oil refineries.

'New information'

Gov. Corzine previously opposed the dredging project because some of the dredged sand and dirt would be disposed of in New Jersey. Corzine eventually agreed to the project.

Collin P. O'Mara, secretary of the Delaware Department of Natural Resources and Environmental Control, signed an order yesterday denying the application.

The Army Corps had asked for state wetlands and "subaqueous lands" permits to remove nearly 19 million cubic yards of material from the channel, which runs from the mouth of the Delaware Bay at Lewes to the Delaware-Pennsylvania border near Claymont.

"The scale of the project has changed substantially from the project envisioned in the 2001 application, and there has been a great deal of new information developed in the intervening period about the Delaware River and Bay," O'Mara wrote in his letter to Army Corps District Commander Thomas Tickner.

'Our next step'

Melinda Carl, spokeswoman for the Delaware environmental agency, said that the agency believed its permits were necessary for the project to move forward and that it hoped the Army Corps would respect its decision.

Army Corps of Engineers spokesman Richard Pearsall said yesterday afternoon that the agency had just received notice of the ruling and that officials had not yet decided what their next step would be.

"We feel basically we have the permits we need to proceed," he said. "We're considering what our next step is. It may be to reapply. On the other hand, we may not."

Maya van Rossum, who heads the nonprofit Delaware Riverkeeper Network and has vigorously opposed the project, hailed the permit denial. "It will have implications for efforts to secure federal funding and other support for the project," she said.

She said that moving forward without the permit would "set very dangerous national precedent that would lay all of our states at the mercy of federal projects that threaten local environments."