Flint, Mich. — A retired general who is coordinating the effort to get the lead out of Flint water lines said plastic pipes are being studied for possible use in the city reeling from two years of contamination problems.
Retired National Guard Brigadier General Michael McDaniel spoke June 8 at Flint City Hall about the first round of bids going out to install new copper service lines from water mains to 500 houses in three high-priority areas.
While copper lines have been specified in the current request for proposals, McDaniel told Plastics News that may not always be the case, as Flint looks to replace roughly 5,000 lead service lines (LSLs) and 10,000 galvanized steel lines, which corrode and form nooks and crannies where lead particles can adhere.
There are another 10,000 lines of unknown composition, he added.
“That's a lot. I think overall we're going to have to do 15,000 to 20,000 homes — funding permitting,” McDaniel said.
Almost four months ago, JM Eagle CEO and owner Walter Wang offered to help the cash-strapped city, which was under an emergency financial manager when the water crisis began in April 2014. As a cost-cutting move, the city's drinking water supply was switched from Lake Huron to the caustic Flint River, without adding corrosion controls. Galvanized pipes rusted and lead pipes leached the toxic metal, which can damage the brain and nervous system, slow growth and development, and cause learning and behavioral problems.
Wang told elected officials on Feb. 22 he would donate enough free polyethylene pipe to replace all LSLs going to homes and businesses. PE is the No. 1 pipe material used in water systems in Europe because it has a long service life, never rusts, never leaches lead, has fused joints that prevent leaks, and is flexible for cheaper trenchless installations.
‘Not ignoring' plastics
McDaniel told Plastics News that JM Eagle's offer prompted his request for a study of PE pipe, as well as cross-linked PE and copper.
“I'm not ignoring the issue,” McDaniel said. “I may not be talking publicly about it, but there are a lot of things we're working on.”
McDaniel said he asked a professor who retired from Michigan State University to provide him with an “independent” evaluation of pipes made from the three materials.
“JM Eagle made their offer in February. I didn't talk to them personally but I got the information and I said, OK, we need to look at this and whether it makes sense,” McDaniel said. “I've got a retired professor from MSU evaluating it for me. I don't have an answer yet. Like me, he's a volunteer so he's doing what he can.”
Flint received $2 million from Michigan to start replacing water service lines. McDaniel said those funds should be enough to do 500 homes at a projected cost of $4,000 each. Pointing to blocks of red on a city map, he said the work will start in areas with dense populations of children and known concentrations of lead and corroding galvanized water lines.
However, a 36-home pilot project that used copper to replace LSLs cost more than $7,000 per line. McDaniel said that's partly because the addresses were “geographically dispersed” across every ward of the 33-square mile city. And, “it was a totally different contract,” he added, “just to see what we had, so the cost was quite a bit higher than what we found in the rest of the state of Michigan from cities that have done this.”
Both PE and PEX pipes cost less than copper and are cheaper to install. PEX is better known for its use in radiant heating systems, but is gaining market share from copper in potable water applications. It resists corrosion, chemicals, abrasions and freezing.
Still, plastic pipes have had an uphill battle against traditional materials in the United States as evidenced in Flint, where JM Eagle hasn't been able to give it away — yet.
“If PE or PEX doesn't make sense for a service line, that doesn't mean it might not make sense in other circumstances,” McDaniel said, pointing to a recent Plastics News story about PE pipe being used to protect the water intake line of the nearby Karegnondi Water Authority from zebra mussels.
The invasive species can't attach to the PE pipe, which also was flexible enough to use horizontal directional drilling to install the last 300 feet under the bed of Lake Huron.
“The thought was: Are there going to be areas where plastic will make more sense?” McDaniel asked. “We have a huge city here and there may be other conditions involved. There will probably be a need for some follow up with JM Eagle.”