The city Department of Environmental Protection said the water supply for the nation's largest city, which comes from 19 upstate reservoirs, is virtually lead-free. It is tested half a million times a year at the reservoirs and at hundreds of sampling stations.
The recently detected contaminations are attributed to lead pipes and fixtures, which are typically found in buildings more than 40 years old.
The city monitors water in older buildings through regular testing as part of the federal Safe Drinking Water Act. In this year's tests, conducted from June to September, 14 percent - or 30 out of 222 tested buildings - showed lead levels higher than the accepted benchmark.
The U.S. Environmental Protection Agency requires local utilities to take action if 10 percent or more of tested buildings have lead levels of more than 15 parts per billion.
Too much lead can damage the brain, kidneys, nervous system and red blood cells.
"The elevations seen in the city's recent tests have been too small to pose clear health threats ... but the best level of lead exposure is zero, especially for children and pregnant women," city environmental Commissioner Cas Holloway said in a statement.
The city said drinking water is rarely the cause of lead poisoning but can contribute to a person's overall exposure.
The guidelines say a tap needs to be run if the water in that faucet has not been used for six hours or longer.
The last time the city's water triggered such a response was in 2005, the DEP said.
In the past decade, other cities have similarly exceeded the EPA benchmark, including Boston, Washington and Portland, Ore.
DO YOU HAVE PHOTOS OR VIDEOS TO ADD TO THIS STORY? CLICK HERE TO UPLOAD THEM TO IWITNESS.7ONLINE.COM, OR E-MAIL THEM TO IWITNESS@WABC.COM