ANCHORAGE - The Coast Guard has knocked down Alaska's tallest structure, along with a part of its maritime and flight communications history.
The agency and a private explosives company on Wednesday demolished a 1,350-foot Long Range Aids to Navigation tower on the Seward Peninsula.
The tower was at the Coast Guard LORAN station at Port Clarence about 70 miles northwest of Nome. It was completed in 1961 and was the tallest tower of its kind in the country.
LORAN is a land-based navigation system that preceded the satellite-based Global Positioning System. Used by vessels and aircraft, the LORAN system put out radio signals that could be used to triangulate a position, said Coast Guard spokeswoman Sara Francis.
LORAN was developed during World War II for military ships and aircraft. LORAN-C was developed for civilian use in 1957 and used signals from 24 land-based towers.
The Coast Guard has maintained the LORAN system for more than 52 years, taking over for the Navy in some cases.
With most operators using GPS, and the government determination that LORAN was no longer needed, President Barack Obama last year ordered stations and domestic signals shut down to save money.
"LORAN was never designated as a backup to GPS," Francis said.
Six U.S. sites continue to broadcast an international signal as part of systems with Canada and Russia, Francis said. In Alaska, Shoal Cove in Ketchikan sends out the international signal as part of Canada's West Coast chain, as does Attu in the Aleutian Islands as part of Russia's Chayka chain, she said.
The domestic signoff was Feb. 8. Besides Port Clarence, that meant closure of LORAN stations at St. Paul, Kodiak and Tok.
"We're in the process of hardening those stations," Francis said, which means removing equipment, data lines and potential hazardous waste. Some had independent power sources.
Most of the other towers also will be removed, she said. Without power, they are not lit and could be hazards to aircraft. They also are deteriorating.
"They would need significant upgrades, if not replacement," Francis said.
The tower at Port Clarence was deteriorating and at risk of collapse.
The Coast Guard's civil engineering unit from Juneau and a private company, Controlled Demolition Inc., used explosives to take the tower down.
The 808-foot Alaska Public TeleCommunications tower in Knik, 30 miles north of Anchorage, is now the state's tallest structure, according to the Coast Guard.