Flint water quality improves, but safety measures still needed, Virginia Tech engineers say
August 11, 2016
The Flint, Michigan, water system is healing.
Lead levels appear to have fallen below actionable limits, according to the most recent testing by Virginia Tech researchers.
In addition, no alarming Legionella bacteria were found in water heaters of random homeowners. And testing has also eliminated concerns about contamination from disinfection byproducts in the water.
But the improvements do not mean Flint residents should start drinking straight from the taps, said Marc Edwards, the Charles P. Lunsford Professor of Civil and Environmental Engineering in the College of Engineering at Virginia Tech.
“What our data clearly shows is Flint water is dramatically better,” Edwards said during a news conference Thursday at the Quillen Family Auditorium in Goodwin Hall in Blacksburg, Virginia. “Residents certainly should continue using bottled water and filters until notification from the Environmental Protection Agency or the state — no one is saying the water is safe.”
Researchers tested water from 162 homes over the summer in sampling led by former Flint resident LeeAnne Walters and funded by the Environmental Protection Agency.
Data presented Thursday by Kelsey Pieper, a U.S. Department of Agriculture postdoctoral fellow at Virginia Tech, shows Flint water appears to be below the lead action level. However, samples were not from an approved Environmental Protection Agency’s (EPA) Lead and Copper Rule sampling pool.
Generally, Edwards said, the numbers indicate lead levels are 50 percent to 80 percent lower than they were about a year ago. The water is clearer and also contains less iron, largely because of corrosion control chemicals that have been flowing through the water system.
“In March 2016 the lead level was 1.5 times the action level,” Edwards said. “Then residents were encouraged to use the water and flush out the pipes.”
Increased water flow allowed anticorrosive chemicals to work, and lead levels apparently fell below the action level by July 2016.
Edwards said the recent sampling was thorough, but the results should not be considered official per the EPA or the state of Michigan. Residents should continue to use lead filters or bottled water.
“As long as good corrosion control continues, things are destined to be better in each round of testing for the next year or so,” Edwards said.
Meanwhile, Virginia Tech graduate students William Rhoads, a doctoral candidate, and Taylor Bradley, a master’s student, both with the Charles E. Via Department of Civil and Environmental Engineering, discovered Legionella colonization rates in Flint homes are also very low.
In a study funded by the state of Michigan, two teams of seven students — with the aid of three community volunteers and three plumbers — tested samples originating from hot water tanks at the source and at various locations in the house, such as the shower.
In addition, they flushed 30 hot water tanks to see whether accumulated sediment was interfering with residual chlorine, which could create a favorable environment for bacteria that causes Legionnaires’ disease or Pontiac fever.
They said flushing did not eliminate or reduce the incidence of Legionella, nor did flushing change levels of lead, iron, copper, or chlorine in the water system. They did not recommend a one-time, short-term cleaning program to flush Flint hot water tanks.
Meanwhile, Edwards said separate water heater disinfection byproduct testing funded by the EPA and led by Dave Reckhow, a professor of civil and environmental engineering at the University of Massachusetts Amherst, found levels of disinfection byproducts were normal.
Edwards said Flint residents experiencing breathing difficulties or rashes are concerned about the chemical byproducts in the water system.
“We feel these fears are justified and we take these problems seriously,” Edwards said. “Given the widespread concern, we recruited the team from UMass Amherst.”
In terms of discoloration and floating particles, the water looks better than it did in summer 2015, when Virginia Tech's Flint Water Study team first worked with Flint residents in a historic sampling that demonstrated serious lead-in-water contamination throughout the city.
Walters, a concerned parent who could not get state or local officials to pay attention to the orange-tinted water coming out of her spigots, contacted Edwards in 2015 to enlist Virginia Tech’s involvement.
Virginia Tech testing showed lead levels were dangerously off the charts, but getting officials to accept the public health problem was difficult, eventually leading to Congressional hearings to investigate the situation.
For Edwards, much of that is water under the bridge.
“Look at what was accomplished,” Edwards said. “EPA experts and state officials have implemented some of the best corrosion control practiced in U.S. When we saw the healing progress was slow, the residents’ water bills were paid for a month to help start drawing water through the system. Since the state of Michigan and others acknowledged the problem, I have been satisfied with the response. This is how science should work. People are doing their jobs and doing them well.”
More information on Virginia Tech’s work in Flint can be found online:
Written by John Pastor