As a power blackout left 620 million people in India without electricity yesterday a top official in the Utility Workers union reminded Americans that big disasters can happen here too.

He noted that it was only nine years ago that a massive blackout shut the lights off across one quarter of the North American continent.

The utility companies claim there’s been major upgrading of the U.S. power grid to prevent a catastrophe like the one that has struck India from happening in America. All claims aside, however, union officials are not so sure.

“Anything is possible,” said Gary Ruffner, secretary- treasurer of the Utility Workers union. “The companies are supposed to have inhibiting protections,” he said, “that now would prevent a cascade of switch failures,” such as the ones that began in Ohio in 2003.

A major switch failed that summer in the Buckeye state, causing switch after switch to fail until major portions of the United States and Canada were in the dark.

The union says the problem in the United States is that with the proliferation of private utility companies a high degree of cooperation between them is required to prevent catastrophe. Union experts think the current level of cooperation leaves much to be desired.

“There isn’t as much cooperation between utilities as there should be,” Ruffner says and he and other union experts think government deregulation of utilities is at least partially to blame.

That means the problem facing Americans is different from the ones that caused India’s blackout this week. The eastern and northern power grids in that country are believed to have failed because of overload. Industry has grown so fast in India that the nation’s power grid became totally overwhelmed. Much of the country, almost a third by many estimates, still has no access to power at all.

Union experts say that in the United States the big danger comes from outdated infrastructure, not from increasing demand for electricity.

According to Ruffner, the old power lines, badly in need of repair, leak 15 percent of the electricity travelling through them.

Utility companies say that since the blackout nine years ago they have improved the switches that tie the regional power grids together and that this should prevent a disaster. None of what they have done, however, addresses the problem of the outdated lines cited by the union experts.

An alternative way to protect the U.S. grid, according to Ruffner, is to replace the nation’s old power lines, conductors and insulators. “But to do that you’d have to shut present lines down or if you can’t do that, you have to build new ones,” he said.

Deregulation of the utility companies ensures that the big thing on their minds is maximum profits, say union leaders, at the expense of things like maintenance.

Unions note that repair of old lines or putting above-ground lines underground would create many of the jobs desperately needed all around the country.

The big problem is that the motivation to do this is just not present.

The private utility companies are so concerned about making money, Ruffner notes, that rather than make needed repairs they actually sell off their power lines altogether, bringing still more private companies concerned about profit into the mix.

The result, he notes, is that Americans must suffer frequent localized blackouts, particularly after powerful thunderstorms or blizzards.

Hundreds of thousands of Pepco customers recently went without power in the Washington D.C. area for 10 days after a line of thunderstorms crossed the area. “Now Pepco is scrambling to repair the grid and trim trees,” said Ruffner. “Pepco blames the trees, not its circuitry’s reliability, for the outages.”

It seems that state officials in Maryland are inclined to agree with the union that the problem lies more with the company than it does with the trees. The state has said the utility is not spending enough to maintain the system and it has denied Pepco’s latest request for a rate hike.

“When utilities can’t maintain the system, the system will fall apart,” Ruffner warns.

Photo: Utility workers repair downed power lines after a rare October snowstorm, Oct. 31, 2011, in Millburn, N.J. Millions of people from Maine to Maryland were without power after the storm. Julio Cortez/AP