August 24, 1999
Old Phone Cables Open Sea Bed to Science
By MALCOLM W. BROWNE
Making use of thousands of miles of discarded telephone cables, scientists have begun to wire remote regions of deep ocean floor to create an undersea network of geological observatories.
The old cables will serve as deep-sea extension cords running thousands of miles from land-based power stations to sensors, some of which are already sending back continuous flows of data from the ocean floor.
One such line is a coaxial cable (similar to the cable that carries television programs into private homes) that was laid across the deep Pacific Ocean floor by AT&T in 1964 from San Luis Obispo, Calif., to Makaha, Hawaii -- a distance of nearly 3,000 miles. At the time, it was among the most advanced phone lines in the world, equipped with powered vacuum-tube repeaters every 20 miles to refresh the telephone signals as they traveled along it. The cable, called Hawaii-2, could simultaneously carry as many as 138 conversations.
But in 1989 a fishing trawler working in shallow water near the California coast accidentally cut the $30 million cable.
The telephone company could probably have repaired the break, but decided instead to abandon the cable; by then, optical-fiber cables had come into use, and the new cables could carry up to a half million conversations with greatly improved sound quality. AT&T announced that it would make the abandoned coaxial cable available to scientists who could find a use for it.