SALEM, Ore. -- President Obama has declared a state of emergency in Flint, Michigan, where high levels of lead leached into the city’s water pipes, poisoning residents.

A series of cost-cutting measures and mistakes by multiple agencies lead to the public health disaster.

But the potential for similar, if less extreme, incidents exists throughout the nation’s aging water infrastructure.

High levels of lead can and do flow from household taps across the country, including some in Salem, Portland and other Oregon cities.

In fact, the U.S. Environmental Protection Agency estimates that 10 to 20 percent of a person’s potential exposure to lead comes from drinking water.

The problem arises in communities that draw water from lakes, rivers and streams, rather than underground aquifers.

“Surface water is the culprit because it’s soft,” said Beth Myers, lab director at Waterlab, a Salem professional water testing company.

Soft, or acidic, water corrodes plumbing, releasing lead from older lead pipes and from lead solder used in copper pipes.

“Lead leaching from plumbing is a common problem in Oregon public water systems that use surface water sources,” said Jonathan Modie, spokesman for the Oregon Health Division.

Conversely, the minerals in hard groundwater, such as that used in Keizer, coat pipes, offering a layer of protection from lead.

“Keizer has no problem at all,” Myers said.

In Oregon, 225 communities use surface water sources.

The state outlawed lead solder in plumbing in 1985. However, homes built before that still are at risk.

In 1991, EPA published a regulation to control lead and copper in drinking water. It requires water systems to monitor drinking water at a fraction of at-risk customers’ taps.

If lead concentrations exceed 15 parts per billion in more than 10 percent of the taps sampled, the water provider must take action to control corrosion in pipes, educate customers about steps they can take to protect their health, and may have to replace lead service lines under their control.

That’s exactly what happened in Salem in 2003.

The city had been sampling water from the taps of 147 homes built between 1983 and 1985, said Lacey Goeres-Priest, Salem water quality and treatment supervisor.

“In 2003, we exceeded the action level for lead,” she said.

In response, the city built a $700,000 addition to its treatment plant on the Santiam River to add soda ash to the water, raising its pH level. It went into operation in 2006.

Since then, the city has not exceeded the EPA action level of 10 percent of taps tested exceeding 15 ppb of lead.

In 2011 and 2012, three homes exceeded that level, with the highest coming in at 40.1 ppb.

The most recent tap samples, taken in 2013, showed that only one Salem home out of 91 tested exceeded 15 parts per billion of lead, at 29 ppb.

The city is scheduled to take samples again this summer.

Salem also began advising customers, especially those in older homes, to flush each of their taps for up to two minutes when water has been sitting in the pipes for six hours or more.

The homes tested are just a fraction of all of the homes in Salem that are at-risk.

The city does not have an estimate of the total number of homes it serves that have lead in their plumbing. Goeres-Priest also was unable to say whether any city-owned service lines contain lead solder.

Portland has struggled with the same problem.

In 2014, the Portland Water Bureau reported that 13 out of 108 homes it tested had water that exceeded 15 parts per billion of lead.

Portland has previously exceeded the EPA’s lead and copper rule five times, most recently in 2006.

In 1997, the city began adding sodium hydroxide, or lye, to the water to raise its pH. The Portland Water Bureau also funds education, outreach and testing for all sources of lead, including lead paint, said Jaymee Cuti, public information officer for the Bureau.

Across Oregon, 89 water systems reported 118 violations of the EPA’s lead and copper rule in 2014, the most recent year for which data is available.

OHA’s Modie said Drinking Water Program staffers could not immediately determine which systems those were, but said all of the violations were for failing to report or late reporting of lead testing results.

Across the state, 130 communities now treat their water to make it less corrosive.

Public health officials say there is no safe level for lead in water.

Exposure to lead can cause health problems ranging from stomach distress to brain damage. Children are especially susceptible because their bodies absorb metals at higher rates than adults.

In Flint, officials ignored complaints about the water for months after the city began drawing its water from the Flint River, in April 2014, as a cost-saving measure. The water was not treated for corrosion control.

Concerns were swept under the rug until a pediatrician documented high lead levels in children’s blood.

Flint reconnected to Detroit’s water system in October 2015, but by then it was too late. Corrosion has flooded the water infrastructure with lead. Replacing the water pipes could cost as much as $1.5 billion, Flint Mayor Karen Weaver said last week.

tloew@statesmanjournal.com, (503) 399-6779 or follow at Twitter.com/Tracy_Loew

Lead in drinking water

Water suppliers are required to send each customer an annual drinking water quality report detailing where their water comes from and what is in it. Contact your supplier for more information.

The city of Salem provides a free lead analysis to residential customers. Call 503-588-6323.

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