Philadelphia's water department insisted the city's water is safe to drink and its testing methods are sound after a news report last week accused it of distorting tests.
The Jan. 22 report in the Guardian cited Philadelphia as one of a number of U.S. cities that "gamed" water tests to downplay the amount of lead in samples.
The city's water department posted a six-page response on its website to address what it called "concerning statements and inaccuracies" in the report.
It says the department doesn't ask all customers to flush their pipes before taking a sample, as the Guardian story said. It says they follow "best practices" in sampling approved by the state.
The Guardian's report comes as Flint, Michigan, deals with a public health emergency over its lead-contaminated water supply.
