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Flint water crisis: Could it happen here?

As more information about widespread lead poisoning from drinking water in the city of Flint, Mich., continues to seep out, people across the nation have asked themselves the same question: Could it happen here?...

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City of Duluth water treatment operator Steven Pitkanen checks the pumping station where caustic soda is added to the Duluth water supply at the Duluth water treatment plant. (Clint Austin / caustin@duluthnews.com)

As more information about widespread lead poisoning from drinking water in the city of Flint, Mich., continues to seep out, people across the nation have asked themselves the same question: Could it happen here?

The News Tribune put that question to Duluth officials, who said the city's water is - by-and-large - extremely safe, thanks in large part to the high quality of Lake Superior water. They also said there is around-the-clock monitoring at a level that seems to have been lacking in Flint.

But despite continued efforts to completely rid Duluth's water system of lead, stubborn remnants of the heavy metal persist. Lead can be found in the joints of the old cast-iron water mains that still serve much of the city, and Duluth has just shy of 2,000 lead pipes connecting mains to curbside valves - about 7 percent of its total connections. On top of that, the city has a large number of older homes with lead service lines or lead-laden plumbing.

Eric Shaffer, Duluth's chief utilities engineer, said the city continues to remove lead components from its system as repairs and upgrades are made, but the legacy of lead probably will remain for years to come.

However, Shaffer says that doesn't necessarily mean the metal poses a threat.

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Fighting corrosion

The problems in Flint arose from corrosive water that caused lead to leach from pipe walls. Flint city officials have subsequently been faulted for failing to use corrosion controls.

But Shaffer noted that the chemistry and clarity of water drawn from Flint River differs greatly from what Duluth pulls out of Lake Superior.

"The first thing to remember is that people drank water straight from the lake with only disinfection until the mid-'70s. So it's an outstanding resource," Shaffer said.

Mark Proulx, a utility operations supervisor, said the water Duluth draws from Lake Superior is exceptionally clear for a surface source. He said the clarity typically exceeds what he's encountered working at other water treatment facilities operating with groundwater.

But however clean the water may be, Lindsey Seifert-Monson, a city water chemist, said Duluth takes additional steps to prevent it from interacting with any lead in the system.

"The way that we control corrosion is to increase our pH, because metals dissolve in acidic pHs. So we raise our pH to a target of 9, and that controls for corrosion," she said, explaining that the city adds caustic soda to the water to boost its alkalinity, a widely accepted practice.

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Lynn Thorp, national campaigns director for Clean Water Action, said: "The ultimate solution is to get lead out of contact with drinking water. However, until we do that, because we cannot do that overnight, we have a really big job to do to continue to improve the other measures we've been taking, for example using corrosion control treatment where appropriate."

Seifert-Monson said Duluth is selective in its corrosion control measures.

"There are also chemicals you can add, such as inorganic phosphates and silicates, but we choose pH control here," she said.

Thorp encouraged a thoughtful approach and said: "I think it makes sense not to use treatment you don't need. We don't want to be dumping chemicals into our water to control corrosion if we don't need to. That's a good practice. It makes sense."

Proulx said the pH level of the city's drinking water is monitored around the clock, with constant adjustments as needed. He estimated that the city spends about $140,000 per year on the caustic soda it uses to keep treated water in the proper zone.

The failure of Flint to exercise corrosion prevention measures came as a shock to Proulx.

"I'm a little bit floored. It should have been flagged right away," he said.

Elevated exposure to lead can lead to a host of problems, including miscarriages, low birth weights for infants, reduced IQs, learning disabilities and attention deficit hyperactivity disorder, among others.

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Monitoring regimen

Every three years, Duluth tests for lead in the water of 30 homes that have lead service lines, plumbing or pipe solder.

"We get a sample that's been sitting stagnant in the pipes for at least six hours, because you want to have time for the water to be in contact with the lead so that you're getting a good representative sample of kind of your worst-case scenario for that house," Seifert-Monson said.

Duluth sends those water samples from homes scattered throughout the city to a lab, and the results are then reported directly to the Minnesota Department of Health.

The Environmental Protection Agency requires cities to take corrective action only when 10 percent or more of the homes tested are found to have lead levels exceeding 15 parts per billion.

During Duluth's latest round of testing in 2013, just one of 30 houses exceeded that threshold. Water from a home in West Duluth was found to have a lead level of 20 parts per billion.

Four additional homes tested in Duluth came in under the EPA limit but had lead levels of more than 10 parts per billion. Those residences were located in Lakeside, Hunters Park and West Duluth.

Stew Thornley, a health educator for the Minnesota Department of Health's drinking water division, characterized Duluth's test results as "a very good sign."

"They're testing for the worst-case scenario, and they keep coming back with virtually nothing. That's pretty encouraging," he said.

Duluth is slated to conduct its next round of lead testing this June.

Seifert-Monson defended the frequency of the city's lead-testing regimen, saying: "You can't reduce your schedule to every three years until you've proven that your corrosion control system is working... You need to have a track record, proving that your lead level is safe."

 

Old homes

People who live in older houses may want to consider having their water tested for lead. Lead pipe was commonplace until the 1930s, and lead solder remained in use for plumbing until the 1980s.

Seifert-Monson said she occasionally receives calls from Duluth residents concerned about the possibility of lead-contaminated water in their homes, but the city lacks an accredited lab to test for it.

"Normally, we will tell people that if you're concerned it's a good idea to get it tested by a certified lab. And in the meantime if you're using water that's been sitting in your pipes overnight, just let the cold water run for a few minutes, so you're pulling fresh water from the main to flush out any water that may have been sitting in the pipes," she said.

Thornley suggested using flushed water not for drinking but for other purposes, such as watering plants. He said taking a shower before you brush your teeth is also an effective way to safely clear water that has been sitting in lead pipes overnight.

There are no hard and fast rules for who should and shouldn't have their water tested for lead, Thornley said. He said the testing typically costs around $50.

Shaffer said people who don't know whether or not they're on a lead service line can check with Duluth's construction services department to determine if any plumbing permits were pulled that indicate a line replacement.

Thorp advocates for more testing upon customer request "to try to find lead in the system, not just for compliance with a rule but in order to identify public health problems."

"I think we need to find a way for public water systems and local health departments and other local authorities to work together to make it possible to test for lead in any home where that is requested," she said, suggesting it could be offered free of charge or at a reduced cost for customers of modest means with lead service lines.

Seifert-Monson said having your water tested can sometimes provide peace of mind.

"More information never hurts, especially if you have young kids in the house or pregnant women," she said. "It's never a bad idea."

Related Topics: HEALTH
Peter Passi covers city government for the Duluth News Tribune. He joined the paper in April 2000, initially as a business reporter but has worked a number of beats through the years.
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