The Coast Guard has determined that the waterway approach to the proposed Weaver's Cove liquefied natural gas terminal in Fall River, Mass., is "unsuitable" for the type, size and amount of traffic it would bring.

The ruling today could all but doom the controversial proposal, which calls for tankers to travel up Narragansett Bay into Mount Hope Bay and along the Taunton River to the Massachusetts port city.

It also led to a stream of statements this afternoon in support of the decision, which Weaver's Cove has 30 days to request it be reconsidered.

In a press release, Coast Guard Capt. Roy Nash said, “Vessel masters would face extraordinary navigational maneuvers when transiting the waterway The safety risks are too great to favorably recommend the waterways as suitable.”

Nash, captain of the port and commander of Coast Guard Sector Southeastern New England, made the recommendation today in a two-page letter.

The Coast Guard assists the Federal Energy Regulatory Commission -- which makes the final decision on the site's viability -- by determining whether the waterway is suitable for LNG transits.

Last summer, the FERC voted, 2-1, not to revisit its earlier decision to approve the Weaver's Cove site for an LNG facility.

The Coast Guard's ruling comes on the heels of a decision to drop a plan for a major LNG terminal in Providence, which would have also required the tankers to travel up Narragansett Bay.

In Fall River, the Coast Guard’s main concern is a tight space between the old and new Brightman Street bridges. The 80-foot wide, 700-foot long tanker would have just about 1,000 feet to maneuver diagonally through an opening with less than 18 feet of clearance, according to the Coast Guard.

The Guard was also concerned that tankers would have to travel within 100 feet of the U.S.S. Massachusetts museum, the Braga Bridge, and the State Pier.

After the analysis, Nash wrote, “I have concluded that such transits cannot be conducted safely on a routine, repeatable basis, and that the risk of a mishap in Mount Hope Bay, and particularly in the Taunton River in the vicinity of the two Brightman Street Bridges, is unacceptably high.”

Earlier this month, National Grid abandoned its pursuit of establishing a major liquefied natural gas marine terminal in Providence.

The decision ended a four-year effort by the company's KeySpan subsidiary to revamp its existing storage facility on the Providence River into a terminal that would receive LNG deliveries by tankers.

Governor Carcieri issued a statement this afternoon applauding the Coast Guard's stance in the proposal for neighboring Massachusetts.

“Hopefully, today’s Coast Guard decision will be the last nail in the coffin for this project,” he said. “With this federal ruling in hand, Weaver’s Cove should finally abandon their ill-conceived and potentially dangerous plan.”

Attorney General Patrick C. Lynch said in a statement that he calls upon Hess LNG "to cease proceeding any further. I hope it recognizes the futility of pressing on. Let me assure all Rhode Islanders that while we celebrate this day, should Hess proceed any further with this ill-conceived and dangerous project, we stand prepared to fight for the rights of our Ocean State, as we have from the outset.”

“The people who live on the water along the proposed LNG tanker route don’t want this terminal. The fishermen and boaters don’t want it. The environmentalists don’t want it. The political leaders in two states don’t want it. And now the Captain of the Port for the Coast Guard says it’s not safe,” state Rep. Raymond Gallison, a Democrat who represents District 69 in Bristol and Portsmouth, said. “It’s time for Weaver’s Cove to face reality: This proposal is unsafe and unwelcome here and the time has come to drop it.”