The Alaska State Department of Transportation has about $68.2 million of the original federal appropriations for Gravina Island access.
KETCHIKAN, Alaska (AP) The chance of building a bridge from Ketchikan to its airport on Gravina Island is remote, according to former Alaska Gov. Frank Murkowski, given the project’s national stigma as “the bridge to nowhere.” He’s suggesting an alternative — an underwater tunnel.
The technology already is in use in North America, Europe and Japan, he said.
The Ketchikan Shipyard could help build prefabricated tunnel sections that would be lowered into a trench on the floor of Tongass Narrows, Murkowski said. He offered his assistance to encourage evaluating a tunnel’s chances, “because I think the community really needs to focus on the viable alternative, and then let the chips fall where they may.”
The Ketchikan Daily News reported Murkowski spoke as the Alaska Department of Transportation is nearly done with an environmental review that will determine the most fiscally responsible alternative for access between the islands.
The review does not include the original state preferred alternative that drew national attention. That project included a bridge from Revillagigedo Island to Pennock Island and a second bridge from Pennock to Gravina Island, home to the state-owned airport and acreage where the city could expand. A small ferry now shuttles airline passengers to the island.
Murkowski, a former U.S. senator, said Congress in 2007 had approved about $330 million for the Gravina Island crossing and it looked as if it would be built. His successor as governor, Sarah Palin, at first supported the bridge link, he said.
“But later, when she became governor, she supported moving the money to the Interior,” Murkowski said. “And there was a need, a tremendous need, for it in the Palmer-Wasilla Highway area. And, as a consequence, the population of the Railbelt area prevailed on the politics of the issue and the money was moved ... into that area.”
The latest environmental review is looking at ferry options and bridge alternatives.
The state Department of Transportation has about $68.2 million of the original federal appropriations for Gravina Island access. The federal money requires a match of about 10 percent from the state, according to spokesman Jeremy Woodrow.
Murkowski outlined various types of tunnels and suggested the “immersed-tube” version.
“The main advantage of an immersed tube is that they can be considerably more cost effective than alternative concepts,” Murkowski said.
Prefabricated tunnel sections in Europe are mostly concrete and a mix of concrete and steel in the United States, he said.
“The sections of the tunnel could be built at the existing [Ketchikan] shipyard, which would stimulate, obviously, the contribution of that organization to the community,” Murkowski said.
Segments would be floated to the tunnel site and lowered into a trench. The top of the sealed tunnel is covered with backfill for the tunnel’s protection and to ensure no movement.
“It’s not a new concept,” Murkowski said. “It’s been around for about 100 years, and there are numerous tunnels in the United States.”
The Holland Tunnel in New York, the Monitor-Merrimac Memorial Bridge-Tunnel in Virginia and the Bay Area Rapid Transit tunnel in Northern California are examples, he said.