Study finds Metro's leaky current worth watching

You may remember that we talked last fall about the Texas Medical Center testing its buildings for the effects of stray current from the MetroRail line — electricity leaks that Metro says are inconsequential, but that observers worry could be weakening the foundations of nearby buildings, bridges, roads and other structures. Well, the preliminary results of those tests are back, and they show worrisome levels of current at three sites. Does that mean buildings are going to start crumbling? Well, no — not yet, anyway.

The three sites are Texas Children's Hospital's Meyer Building, 1919 Braeswood, and two groups of underground chilled water and steam pipes at the northeast corner of Fannin and John Freeman. And though there's no damage to any of the sites yet, officials will be keeping an eye on them:

Steve Swinson, president and CEO of Thermal Energy Corp., which owns the pipes and is owned by nine TMC institutions, said that although he knows of no damage so far, stray current can cause major damage to metal objects such as pipes and reinforcing steel over time.

The report does not detail what effects, if any, the current has had to date.

"I don't think at this point we would be seeing damage," Swinson said. "But we don't know what it's going to be the next day.

The report, conducted by Corrpro, also found "inconsequential" stray current at The Methodist Hospital, the UT Medical School, St. Luke's Medical Tower, the Memorial Hermann Professional Building, Ben Taub General Hospital, the Fannin-Holcombe Garage and a parking lot east of the Meyer Building. No stray current was detected at Texas Children's, Memorial Hermann, the M.D. Anderson Cancer Center and the TMC Garage No. 1. And though the amount of stray current is small — Metro has compared the leakage each day to the amount of power put out by a 9-volt battery — it is likely to increase as the MetroRail line ages, the report says. "Actions by Metro are essential to control stray current levels to within acceptable limits," the report's authors wrote.

Metro tried to highlight the good side of the study, KHOU notes, releasing a statement that pointed out that only two sites (counting the two sets of pipes as one) needed continued surveillance and that only seven more showed signs of stray current — which means four sites had no problems at all! And, as Metro's John Sedlak told the Chronicle, the agency has solved the leaky current problem across 85 to 90 percent of the seven-mile rail line. "We continue to do the readings and we're still trying to bring it to final resolution," he said.

- Read the executive summary of the report, from KHOU

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Photo: flickr user phototainable