PORTLAND – U.S. Coast Guard officials said the agency remains at the highest state of alert since World War II, but security measures are being adjusted for long-term vigilance.

Coast Guard spokesman Mike McCarthy said the agency wants to establish security policies that are sustainable for months, or possibly years.

“This is the new normal day-to-day,” he said Wednesday.

An extended alert will involve a rearrangement of priorities.

Before Sept. 11, for example, the Coast Guard would respond to a sighting of a mystery sheen of oil in the harbor, McCarthy said.

“Now, unless you have a good size spill, with several hundreds of gallons, we aren’t going to bother,” he said. McCarthy said state environmental agencies will now respond to small spills.

For two weeks after the Sept. 11 terrorist attacks, Coast Guard crews in Portland Harbor escorted all cruise ships and tankers carrying flammable cargo, such as gasoline and jet fuel.

But since Sept. 26, they have become more selective, escorting some of these vessels but not all.

“If we had maintained the tempo we had,” explained John Stevens, a Coast Guard reservist, “we would have burned everyone out.”

Coast Guard crews in Portland continue to board cruise ships and tankers with flammable cargo, but they board them in different locations, depending on whether the ships are from U.S. or foreign ports.

Crews board the ships at anchorage if they come from foreign ports. They board them at dock if they come from U.S. ports. They also board ships at dock if they traveled from Canada but had originated in the United States.

“The events on Sept. 11 changed not only our nation but the Coast Guard forever,” said Tony Soliz, operations officer for the Coast Guard at Portland.

In the weeks after the Sept. 11 attacks, the Coast Guard in Portland was “stretched to the limit,” according to testimony prepared by Portland transportation director Jeff Monroe for a Thursday hearing held by the U.S. Senate Committee on Commerce and Transportation.

Monroe said the Coast Guard needs more money and more people.