FLINT, Mich. -- The Michigan Department of Environmental Quality will present its comprehensive testing plan for Flint water to federal officials today based on monitoring hundreds of new sites around the city and mapping all of the system's lead piping that leached toxic metals into the city's drinking water supply.
The goal is to come up with a reliable health assessment for much of the contaminated system by April 14, when the current state of emergency is to end.
Other state officials said it's possible that various portions of the city could be given an all-clear in conjunction with local, federal and independent experts before mid-April on a rolling basis. The process also is likely to identify so-called hot spots where more costly remediation, including lead pipe replacement all the way to the tap, may be necessary, officials said.
In an interview Sunday afternoon, DEQ Director Keith Creagh said his department will outline the plan to federal EPA officials today, including department-led sampling at 200 representative sites starting next week. The plan anticipates four rounds of testing, which takes about two weeks for each round to establish a baseline for lead in the water and where people are being exposed to contaminants, he said.
It would be in addition to the nearly 5,000 water samples submitted by residents that have already been tested.
At the end of the process, Creagh said that he hopes "to be able to say something about the general health of the system come mid-April." The proposed testing plan will be presented to federal regulators as well as independent water system and lead contamination experts for approval before going forward, he said.
Reception to the plan could be one of the first big tests for Creagh, who took over the DEQ amid controversy in late December. Gov. Rick Snyder earlier had accepted the resignation from then-Michigan DEQ Director Dan Wyant after a task force called his department responsible for much of the Flint water crisis.
The crisis spawned from the city's switch to using the Flint River in 2014 as a drinking water source after leaving the city of Detroit's system, which draws water from Lake Huron. The result was water pumped through city pipes that leached lead. The system switched back to Detroit late last year.
DEQ officials belatedly acknowledged the mistake after months of complaints by residents about the discolored, malodorous water causing a variety of ailments. State regulators said they had been confused about federal regulations requiring steps to make the water less corrosive.
While the city's plan could bring some relief to sections of the city within weeks, there are some big caveats. The system may need to be tested in both warm and cold conditions, which could extend some testing at least through summer, according to Creagh. Officials also will need to examine the impact of construction and other disruptions on the integrity of the system.
For now, Creagh reminded all Flint residents that they should have their water tested for lead. For those households with elevated levels of 5 parts per billion or more, babies should drink bottled water.
Work on fixing Flint's drinking water is progressing on several fronts, Creagh said.
The federal Department of Health and Human Services is expected to update Creagh today about the residual impact of chlorine added earlier to city water. Last week, the U.S. Environmental Protection Agency said its most recent samples show bacteria has not creeped into the system, an indication that added chlorine may be working.
Flint had difficulties in the past controlling bacteria in its drinking water. But others have worried about the impact of chlorine on residents' health.
Despite the switch back to a Detroit water source, Flint still has severely elevated lead levels in some parts of the city based on testing released Friday, stoking new concerns.
Creagh said he also is learning more about the testing overseen by state and federal environmental protection officials. It found extremely high lead level levels that ranged from 153 parts per billion to more than 4,000 parts per billion at 26 sites after more than 4,000 samples of unfiltered water taken since late December were analyzed.
The lead filters distributed to residents and business in Flint by officials only have an NSF International certification to treat water with up to 150 parts per billion of lead, raising doubts about their ability to protect residents from elevated lead levels.
If tap water contains lead at levels exceeding the 15 parts per billion action level set by the EPA, the federal Centers for Disease Control and Prevention recommends taking action to minimize exposure, although no level of lead is considered safe.
There is a possibility that the elevated results starting in late December came from built-up sentiments moving through the system temporarily, but "we want to make sure of that. We need to look at more of the water and plumbing structure and that's a great effort," Creagh said Sunday.
The latest testing shows that the extremely high levels are still relatively rare in the city, Creagh said.
In total, 4,924 samples of Flint water have been tested through Jan. 30. Ninety-four percent, or 4,616 sample sites, were at or below 15 parts per billion. Of the total, 4,179 samples were 5 ppb or less, he said. That meant the remaining 30 samples taken from 26 locations had levels at 150 ppb or above.
The broader testing plan to be presented to federal officials today relies on several sources of information about the condition of the water system collected by the city, state and federal officials, but much remains unknown.
Of the city's 56,000 land parcels, about 5,200 have lead service lines. But roughly 25,000 parcels have piping of an unknown origin. Determining how much of that piping is lead is a crucial step for any remediation, officials say.
The remediation strategy under development by state environmental quality department officials also counts on using several sources of information about the city's infrastructure. It includes the location of lead service lines, the age of the pipes, the length of time water has been sitting in the pipes as well as the homes with elevated lead in the water and blood samples of residents indicating high lead levels.
That is all expected to be combined with data about whether a home is occupied so that resources can be targeted toward where people live.
"It's so we can actually start making some informed decisions," Creagh said.