New York: For years, scientists at utilities around the United States have tried to peer deep into the guts of their cities without resorting to ground breaking equipment.
They have experimented with robotic probes, ground-penetrating radar and thermal cameras, all ways to identify dangers like frayed electrical wires or leaking pipes before they turn into disasters like the steam eruption that caused chaos in Manhattan nearly two weeks ago.
Engineers in New York and elsewhere have tested a variety of space-age contraptions, but good solutions have been elusive in trying to pinpoint the danger that lurks below.
“We are looking all over the world for the best technology,” said Fred Coppersmith, a research director at Consolidated Edison Co., a power provider.
After a morning of downpours on the day of the Manhattan steam blast, Con Ed resorted to an old-fashioned method for identifying spots where hot pipes had come into potentially dangerous contact with cold rainwater: It sent employees out in trucks to look for manhole steam.
That system failed to detect anything amiss. Hours later, a steam main near Grand Central Terminal exploded, creating a colossal geyser that swallowed a truck, tore a 25-foot-deep crater in the street, burned bystanders and showered the neighborhood with toxic debris. One person died of a heart attack and more than 40 people were injured.
Companies that have gone hi-tech
* Con Edison is using higher-tech methods to find problems in the country’s aging infrastructure.
*Trigen Companies operates steam systems in 11 cities, including Boston, Philadelphia and Las Vegas. It occasionally flies thermal cameras over its networks, looking for heat plumes that might indicate a steam leak, or pooling groundwater in the area of a pipe.
*Matcor, a Pennsylvania-based corrosion control company gets its engineers to use sensors that analyze electrical fields to determine whether there are flaws in the protective coatings on buried pipelines.
Oil and gas companies check the integrity of their larger lines with mechanical probes called intelligent pigs, named for the squealing sound they make as they travel through the pipe.
Con Ed has also experimented with peering into its pipes and cables using ground-penetrating radar, like the kind the military uses to uncover land mines, and with a device that projects sound waves into the tubes to look for defects. Another contraption lets inspectors listen for the whistle of escaping steam or gas.
Technology will get better
None of these systems are ready yet for widespread use, but Coppersmith said he believes the technology will improve.
Years of study and help from a Department of Energy laboratory has enabled power companies in the U.S to begin injecting cables with chemical compounds that can be traced with sensitive air sampling equipment if a line broke.
Ultimately, you will be able to wear a pair of goggles connected to something on your belt and be like Superman and look into the ground, although maybe not in my lifetime, said an inspector with one of the firms.