New Jersey's U.S. Senators and Gov. Phil Murphy asked the Coast Guard to stop opening the Portal Bridge during rush hour in an effort to provide much-needed relief to train commuters.

U.S. Senators Bob Menendez and Cory Booker, D-NJ, were joined by Murphy who wrote to the commandant of the United States Coast Guard Friday. They asked the Coast Guard to close a loophole that allows the bridge to open during a limited time period in the morning and evening rush hour.

The problem with the century-old swing bridge is that when it rotates to open, it sometimes gets stuck and can't be closed, delaying tens of thousands of NJ Transit commuters and Amtrak passengers.

On Tuesday, the bridge got stuck twice, once in the morning and once at 3:24 p.m. It didn't fully close until 4:52 p.m., eight minutes before start of the rush hour. That caused 90-minute delays to NJ Transit trains.

Coast Guard regulations prohibit the bridge from being opened between the hours of 6 a.m. to 10 a.m. and from 4 p.m. to 8 p.m., Monday to Friday. But there is a loophole.

Boat crews can ask for the bridge to be opened as long as they call one-hour ahead of time. "We urge you to revise your regulations to eliminate these loopholes and to end the opening of the Portal Bridge during the morning and evening rush hours," the officials wrote.

Long term, NJ Transit and Amtrak have reapplied for federal grants to help fund a proposed $1.5 billion replacement of Portal with a bridge that is 50 feet above the river and doesn't have to open-up.

That application is being re-evaluated by the Federal Transit Administration.

Larry Higgs may be reached at lhiggs@njadvancemedia.com. Follow him on Twitter @commutinglarry. Find NJ.com on Facebook.