Flint tests show small lead uptick below federal limit

New water testing at targeted Flint sites revealed a slight uptick in lead levels but remained below the federal action limit for the second straight round -- another positive sign for the city’s troubled water system, Gov. Rick Snyder said Friday.

Lead levels were expected to rise with warmer weather but only a small change was observed, the governor’s office said Friday in releasing the latest results from the state’s Extended Sentinel Site Program.

More than 91 percent of the higher-risk target sights tested at or below 15 parts per billion lead. Previous results released last month had shown 93 percent of sites testing below the federal action limit.

The 15-parts-per-billion standard is level at which the federal government advises people to avoid or minimize drinking the water.

In the new tests, more than 85 percent of the sites tested below 10 parts per billion, which Snyder has proposed as a tougher action limit that would exceed federal standards.

“These results demonstrate that the combination of regular flushing, cleaning aerators and using filtered water routinely is making a difference in reducing lead levels in the water system throughout the city,” Snyder said in a statement.

The federal Environmental Protection Agency last month affirmed that filtered water is safe to drink for all residents, including pregnant women and children. Filters provided to residents are rated to handle 150 ppb lead.

But officials have not yet declared Flint water safe to drink without a filter, a decision that Snyder has said will be based on science and data.

Snyder and Flint Mayor Karen Weaver continue to encourage residents to “flush” their faucets on a daily basis, part of a larger effort to push water through the system and remove particulate lead.

Experts believe aging underground pipelines were damaged when the city used harsh Flint River water between April 2014 and Oct. 2015. State regulators had failed to require corrosion control chemicals that experts say could have prevented lead from leaching into the water.

Flint is back on Detroit’s Lake Huron water source while it awaits completion of a new regional pipeline being constructed by the Karegnondi Water Authority.

The state helped facilitate that switch, and the budget Snyder signed last week features an additional $165 million in state aid for Flint, including $25 million in supplemental funding to help replace underground pipes.

joosting@detroitnews.com