How Philadelphia schools' vast effort to rid water of lead went under the radar

As long as six years after the school district learned of possible contamination, the EPA required testing across 300 schools in what was one of the largest such efforts in the country - but 'people have no idea', says a watchdog

After the Philadelphia school district failed to tell the public about lead contamination in school water for as long as six years, officials in the city undertook one of the largest remediation programs in the nation to try to get the lead out.

But with $5m spent and 20,000 water sources tested, few people know about the project, why it left spray painted "do not drink" signs above taps in nearly every school, or why the Philadelphia school district continues to struggle to provide students with access to water.