Lead-contaminated water is on many minds these days, given the crisis in Flint, Michigan, and, closer to home, discovery of high lead levels in water fixtures at two Gig Harbor schools last week.
In Flint, the decision to switch the city’s water supply from the Detroit municipal system to the Flint River saved money but might have exposed thousands of children to lifelong neurological problems because the replacement water wasn’t properly treated.
Gig Harbor’s case pales in comparison. The school district announced last week that routine tests found water from two fixtures exceeded allowable lead levels. The fixtures were replaced and the district is monitoring the quality of well water that supplies the schools.
Tacoma Water, Pierce County’s largest water purveyor, has its own history of problems with lead. In 1992, seven of the 12 biggest water systems in the state, including Tacoma Public Utilities and Seattle, failed a federal test for acceptable levels of lead in drinking water. The Environmental Protection Agency had recently set its “action level” for lead in drinking water to 15 parts per billion.
At the time, Tacoma started testing water in residences multiple times per year, then once a year. It built a corrosion control plant in 1997.
Now, the utility tests water in 50 residences every three years, with the latest round due this year. Selected residences are those most at risk of lead contamination. Plumbing of residences built before 1986 often had lead solder, which can leach into water that hasn’t moved in pipes for a while.
The News Tribune sat down with Tacoma Public Utilities Deputy Water Superintendent Chris McMeen and water-quality engineering supervisor Craig Downs to talk about the system’s challenges, the source of Tacoma’s water and how residents can protect themselves from lead.
Q: What are the differences between Tacoma's water source and Flint's?
Downs: Lead is something that doesn’t come from the source water typically. … It’s not in the water we treat and it’s not in the water we provide to customers’ homes. It comes as a result of wearing or eroding, and typically it’s people’s fixtures within their homes. As a water utility, we are trying to make sure the water doesn't do that, isn’t aggressive on people’s plumbing, isn’t corrosive on people’s plumbing.
There's no lead in the Green River at detectable levels. There's no lead in the wells we use in town.
Lead is something that doesn’t come from the source water typically. … It comes as a result of wearing or eroding and typically it’s people’s fixtures within their homes.
Craig Downs, water quality engineering supervisor for Tacoma Water
McMeen: I think it’s an important subplot of how Flint unfolded. When they moved to the Flint River, which is an urban, highly vulnerable watershed with known industrial contamination, they were focused on, initially, the impact that change in water chemistry on unlined cast iron pipe, which is a common distribution piping material. Cast iron with no lining on it. So you had exposed iron and probably every system in the country has it. We have it. The chemistry in the water changed that iron and caused shedding of the iron.
The bottles you’ll see that are orangish-reddish color, are really iron coming off the pipe. That’s what alerted customers that something was really different. That iron had multiple impacts: visual, trust, taste. But it also consumed the chlorine in the system. Not too long into the change, the chlorine was getting consumed and they had bacteriological problems. They had an E. coli event and they had a boil-water notice. Their response to that was to increase the chlorine in the system. Understandable. They wanted to get the bacteria out.
When you add chlorine to river water, treated or not, they form disinfection byproducts. Those disinfection byproducts were high enough to trigger a violation of regulatory requirements.
If you look at what was happening in Flint that first summer, those were the problems they were chasing. The iron, the chlorine, the disinfection byproducts. They weren't really focused on lead. They weren't aware a lead issue was going on until later it was discovered.
We have a very protected high-quality mountain water supply with low organics. We don't have the kind of disinfection byproducts that Flint has. …
The fundamental difference between Tacoma and Flint is the materials that were commonly used in the older, East Coast cities that were entirely lead. The line from the main out in the road to the home through the meter were lead service lines.
The fundamental difference between Tacoma and Flint is the materials that were commonly used in the older, East Coast cities that were entirely lead.
Deputy Water Superintendent Chris McMeen, Tacoma Public Utilities
Q: Tell us about the Green River watershed.
McMeen: The watershed itself is about 230 square miles in size. We own about 11 percent of the land along the water bodies. About two-thirds of the land area is closed to public use and recreational use. The majority of the land is in commercial timber. … We have inspectors who control the lands who make sure sanitary practices are in place.
Q: What are some of the challenges to water quality for our source?
McMeen: It’s a natural and wild environment. Difficult weather is one. We have landslides and storm events. Keeping road access open and available to patrol the land is a challenge. We do get seasonal turbidity — dirt in the water — and that was one of the major drivers to filtering the supply, which brought us a lot of reliability in these winter conditions.
Q: How does household water sampling for lead work?
McMeen: We make contact with the customer. We provide them information about how to sample, when to sample and give them the sample bottle.
It needs to be a first-draw sample under the regulatory requirements after a period of stagnation. Of course, the natural time to do that is first thing in the morning before you flush the toilet or take a shower. Since it would be very difficult to arrive at everybody’s house and say “wake up,” that is the way it’s typically done. We work with the public to collect the samples.
In the end all we have is their word for it that they did it correctly.
The rule requires a six-hour stagnation period (before drawing water for testing). That’s another place where Michigan got a little weird. Their state guidance recommended people flush for five minutes six hours before they sample. I don’t know why. I actually went back and made sure our guidance didn’t say that — it doesn’t. And certainly the state guidance doesn’t say that.
Q: How often does the utility test for lead in drinking water and how are homes selected?
Downs: When we first started sampling in the early 90s, the initial requirements, we had to sample from 100 homes.
In the early rounds, we did exceed (acceptable) levels of lead, which lead to the corrosion control facility. Once we had corrosion control in place, the sample results came down and eventually we were able to go from that 100 rounds of samples down to we now sample 50 homes on a triennial basis (every three years).
Q: If you find a sample with elevated levels of lead, does that mean you should do more corrosion control?
McMeen: If an individual sample is high and the bulk of the connections are good, you likely can’t treat the water to be non-corrosive to their situation.
What we’ve always done — and is recently required — is we would talk to that homeowner. For some reason there’s a high level of lead in this sample. Systemwide we’re OK. There’s something going on here. We’ll certainly work with them and try to identify what it is. There’s really nothing we can individually do other than be a resource.
Q: Utilities recommend customers flush their water after it’s been sitting in pipes for several hours. What does that mean?
McMeen: Go to the tap you typically drink from, which in our house in the kitchen tap. Typically one of the best ways to tell is when it cools down — 45 seconds to a minute.
Downs: Looking for that temperature difference is a pretty good indication that you’re getting fresh water ... . It goes counter to water conservation, where you want to preserve every drop. I know personally if I was to pull up the first glass of water, it doesn’t always taste the greatest. It’s kind of warm, it’s been sitting there.
Looking for that temperature difference is a pretty good indication that you're getting fresh water. It goes counter to water conservation where you want to preserve every drop.
Craig Downs, water quality engineering supervisor for Tacoma Water
McMeen: Take a shower first and then run your sink for a few seconds.
Q: The government was telling people in Flint that the water was safe to drink. It might be off-color, but it’s fine. Why should people trust Tacoma’s results?
McMeen: We fundamentally start from a better place, frankly, with our situation and our water supply. We have testing in place. We are aware of these issues. We have treatment in place to address them and we are certainly open to talk to any customer about it.
Steps to reduce lead in drinking water
Lead does not occur naturally in the Green River or in Tacoma Public Utilities’ groundwater wells. Lead in drinking water in the TPU system typically comes from household plumbing.
Run your water after you wake up. Take a shower, flush the toilet or open the taps for a couple of minutes — until it feels colder — to flush out stagnant water before you drink it.
Consider filling a pitcher of water after the tap has been flushed and drink from that water.
Residences most at risk are those built from 1983 to 1986. Much of the lead in plumbing solder installed before 1983 has likely leached out by now, and after 1986 lead solder for household plumbing was banned. Brass connections that contain traces of lead can be a concern.
Source: Tacoma Public Utilities