Residents in San Juan Capistrano are raising questions about health effects from a proposed upgrading of high-capacity power lines that run above homes, The Orange County Register reported Thursday.

The higher-capacity lines are part of the San Diego Gas & Electric Co.’s plans to replace a nearly century-old power substation in a residential neighborhood.

SDG&E, which provides power to much of South Orange County, says the added capacity is needed to meet growing electricity demand and make the power grid more reliable, according to the Register.

But many of the substation’s neighbors, who live in homes beside and underneath the lines, are worried about how the increased electricity flow will affect their health.

From the Register story:

Butchie Porter moved to San Juan Capistrano in 1959 and lives in a house beneath the substation lines in an area known as San Juan Park. She said she is concerned about the health effects of increased electromagnetism brought on by the higher-capacity lines.

Porter’s daughter, Tammie Payne, 54, grew up in the home and said she was diagnosed with breast cancer at age 41 and is in remission.

“There were three of us that got cancer around the same time,” Payne said. “They both had bone cancer, and one has since died.  It just seems like a lot when you look at just 35 homes in the area. …”

SDG&E says the new substation is designed to meet the energy needs of South County residents for at least the next 60 years. Usage more than tripled between 1984 and 2010 as the population grew and homes consumed more energy because of entertainment systems, computers and other electronics, [spokesman Duane] Cave said.

SDG&E plans another public forum about the project from 4 to 7 p.m. Wednesday at San Juan Hills Golf Club, 32120 San Juan Creek Road, San Juan Capistrano.

The Register story didn’t mention any SDG&E response to the health concerns. Scientific research on the issue has so far proved inconclusive.

Some studies have shown a correlation between increased leukemia cases and exposure to electromagnetism, according to a 1999 National Institute of Environmental Health Sciences report commissioned by Congress.

But evidence of health problems is “weak,” the report said, since nearly all laboratory tests have failed to show a causal relationship.

Even so, exposure to electromagnetic fields “cannot be recognized at this time as entirely safe because of weak scientific evidence that exposure may pose a leukemia hazard,” the report concluded.

— NICK GERDA

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