Lead pipes lurk in older neighborhoods across the nation
Lead pipes like the ones that led to contamination of the tap water in Flint, Mich., carry water into millions of older homes across the U.S. every day, a legacy of an era before scientists realized the severe long-term health consequences of exposure to the heavy metal.
Replacing these buried pipes would be costly in many cases, so chemicals often are added to prevent the plumbing from corroding and leaching lead and other dangerous metals into the drinking water. That’s a step authorities in Flint failed to take, for reasons that are being investigated.
Some researchers question whether chemical treatment and routine testing for lead in the water are enough, arguing that the only way to remove the threat is to replace the pipes.
Utility operators say what happened in Flint – a largely poor and predominantly black city of about 100,000 people that was once an automobile manufacturing powerhouse – is unlikely to be repeated, pointing to a series of mistakes at every level of government.
The city began drawing drinking water from the Flint River, and state environmental regulators failed to make sure the corrosive water was treated to prevent leaching from old pipes. The result: Flint children have been found with high blood levels of lead that could cause lifelong health problems, and residents are furious at public officials.
Lead pipes are found mostly in older neighborhoods, especially in the East and Midwest, because most cities stopped installing them in the 1930s. The pipes carry water from main lines under the streets and into homes.
Estimates vary on how many of these pipes are still in use. A survey just completed by the American Water Works Association puts the number at 6.5 million. Inside homes, lead also can be found in faucets and in the solder that is used to join water pipes, but that is considered a less-serious concern.
To stop lead from seeping into tap water, chemicals to protect the pipes commonly are added to the water during the treatment process. Some utilities also adjust the composition of their water to limit its corrosiveness.
The U.S. Environmental Protection Agency requires all drinking-water utilities to test for lead. The frequency of the testing can range from six months to every three years.
The reliability of such testing is a matter of debate. Often, a few homeowners are given instructions and asked to provide samples of their water, which is analyzed by regulators. That, of course, does not guarantee all homes are lead-free.