Report: Faulty Tests Downplay Lead Levels At Top Utilities

Water utilities in major U.S. cities check water quality with tests that downplay lead levels, according to a new report.

The Guardian investigated testing methods at major U.S. utilities and found current methods to be “improper.”

“In the tests, utilities ask customers who sample their home’s water for lead to remove the faucet’s aerator screen and to flush lines hours before tests, potentially flushing out detectable lead contamination. The distorted tests, condemned by the Environmental Protection Agency, have taken place in cities including Chicago, New Orleans, Philadelphia and Columbus, Ohio. The improper screening could decrease the chance of detecting potentially dangerous levels of lead in water, the EPA has said,” according to the report.

The newspaper previously reported on documents revealing “that water boards in cities including Detroit and Philadelphia, as well as the state of Rhode Island, have distorted tests by using methods deemed misleading by the Environment Protection Agency.”

University researchers corroborated the claim that current testing methods are insufficient.

“Virginia Tech University researchers who helped expose the lead problem in Flint say the U.S. Environmental Protection Agency's 1991 rule that governs how water utilities test for lead fails to provide adequate protections and needs to be updated,” Michigan Live reported.

Michigan Live summarized the testing method that has come under scrutiny:

Typical testing protocol is this: A customer in a home with high lead risk fills a provided bottle using instructions from the utility after water has been inactive, or stagnant, for at least six hours. They record which faucet was used on a form and the utility collects the bottle, usually giving the customer a small credit on their bill.

Most utilities ask for a "first draw," or a liter of the very first liquid to exit the tap after the designated waiting period. The testing hopes to ensure no more than 10 percent of the population is drinking water with lead above the "action level," at which expensive corrective steps are required. On municipal water quality reports, it's called "90th percentile" test — meaning 90 percent of tested homes must register below 15 ppb before the EPA requires the utility to begin taking measures to fix the system.

That’s a problematic approach, according to researchers.

“Unfortunately, first draw samples are not typically catching the water in the lead service lines, said Daniel Giammar, an environmental engineering professor at Washington University in St. Louis, Mo. Ideally, sampling should collect as many as 20 sequential liters from a tap that has the aerator removed, he says,” Michigan Live reported.

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