When Virginia Tech civil engineer Marc Edwards tested homes in Washington D.C. for lead in the water a year ago, he found levels that were so high his instruments couldn't measure them. Now, the district’s government and the EPA are beginning to react. Host Steve Curwood discusses the crisis with Mr. Edwards.
CURWOOD: It’s Living on Earth. I’m Steve Curwood. Last year, at the request of some Washington, D.C. residents, Marc Edwards, a civil engineer and corrosion specialist with Virginia Tech, began testing the quality of drinking water being piped into their homes. Soon, he says, he found concentrations of lead in that water that he describes as being literally off the charts. Some of the levels were so high that the water could be considered hazardous waste.
Professor Edwards took his concerns to the U.S. Environmental Protection Agency and the District of Columbia Water and Sewer Authority – called DCWASA. But Marc Edwards says the agencies paid him no heed and after he persisted, a contract he had with the EPA to test water mains in the District was terminated. Then, last month, he went public with his findings, and he joins me now. Mr. Edwards, why did you discover problems with lead in the water when the EPA didn’t?
EDWARDS: It had long bothered me that the U.S. EPA sampling protocol did not collect water that had been contacting, in many cases, the worst lead plumbing. The sampling protocol, unfortunately, did not even measure the water that would be consumed by someone who is following the EPA’s own recommendations.
CURWOOD: Which were?
EDWARDS: To flush the tap for one minute and then consume a sample for drinking. So in my sampling of March 2003, I resolved to sample that water and that was, in fact, when I found the highest amounts of lead. So, in other words, consumers following the published advice were actually drinking water with more lead in it in many cases, and not less.
CURWOOD: So tell me, how that could happen? Why would it be worse to do what the government tells you to do to protect yourself against lead?
EDWARDS: Well, the advice was given with the best of intentions. But the reality is that in DCWASA, at that one minute flush time or perhaps a little bit thereafter, that’s when the very worst water is coming out. That’s the water that’s been contacting the most problematic plumbing materials.
CURWOOD: Let’s look at what’s causing this problem. Now, if I understand it correctly, a large part of the problem has to do with the fact that the District of Columbia switched from using ordinary chlorine to disinfect water to something that included some ammonia, some chloramine, if you will.
EDWARDS: Correct. The effective change that has occurred is that in addition to adding chlorine, they’ve also started to add ammonia to meet new EPA regulations.
CURWOOD: And they were adding this because the chlorine itself was leaving behind some organic chemicals that might be considered cancer causing. Do I have that right?
EDWARDS: Correct. Based on the science as we understand it, there are concerns that chlorine produces some byproducts that might be harmful. And the EPA was well- intentioned in trying to minimize the amount of those byproducts that are produced.
CURWOOD: So then, how does the addition of ammonia lead to a lead problem?
EDWARDS: Well, there are many factors that are actually combining at DCWASA to create the perfect storm in terms of lead corrosion. The very first factor that we have proven now in our laboratory experiments at Virginia Tech, is the fact that chloramine itself greatly increases the amount of lead leached to water from either brass or from pure lead pipes. We’ve also discovered that there are other trace constituents in the DCWASA water that are exacerbating the problem and speeding up the rate of lead corrosion.
CURWOOD: Uh, huh. So it’s a combination of using some of the chemicals in the water itself – if there’s ammonia there they help attack the lead that’s in the pipes and free it.
EDWARDS: That’s correct. In some systems we believe the chloramines themselves will not cause a problem. It requires other factors, as well.
CURWOOD: Now, why does brass lead to lead poisoning?
EDWARDS: Well, the Safe Drinking Water Act actually allows lead-free brass to contain up to eight percent lead by weight. So this is a major problem with the Safe Drinking Water Act itself that I hope Congress can soon rectify.
CURWOOD: So, who has to worry about this – just homes with lead service pipes? Are those the only ones? Homes with lead service pipes and brass? Who should worry about this?
EDWARDS: In DCWASA right now, I’m worried about everyone. The EPA has largely been assuming that this is a problem restricted to homes that have lead service lines or lead pipe taking water from the water main into the consumers’ homes. But our results at Virginia Tech have shown that even homes – new homes – with this so-called “lead-free” brass, might be experiencing a very significant problem as well. Although not anywhere near the magnitude that is being seen in homes with pure lead pipes.
CURWOOD: As I understand it, the District wants to replace the lead service pipes on city property leading up to the private property line at the house. How effective is that method, do you think?
EDWARDS: I have opposed that procedure in the strongest possible terms. The way in which they go about that partial lead service line replacement is to cut out the front half of the lead pipe and replace it with a new copper pipe. The new copper acts as a battery that literally forces the lead that remains in the water to corrode at a much, much higher rate. So, as a result, it doesn’t really matter that you’ve reduced the amount of lead pipe by, perhaps, a factor of a half. Because even one foot of a lead pipe has enough lead in it to cause a problem with every drop of water that a typical family would use for more than a hundred years.
CURWOOD: So, what would you do?
EDWARDS: The short-term solution is to make sure consumers have filters that remove lead from the water. Intermediate-term, the only possible way to address this problem is to reduce the corrosivity of the water itself. And that’s the action that the District hopes to implement over the next six months. The long-term solution is to eventually replace all significant lead-bearing materials that are used in the water system. But this is going to take generations to implement, and it’s a job that will not be completed in my lifetime.
CURWOOD: I have to say, listening to this story, that I’m greatly concerned that a number of cities around this country will be suffering from this, that D.C. isn’t just an isolated case. How real are my worries?
EDWARDS: I fervently hope that this incident in D.C. is an isolated case. But the reality is we’re simply not conducting the sampling necessary to know.
CURWOOD: How many cities are doing the chloramine approach now to disinfecting water?
EDWARDS: As we speak, many of the biggest utilities in the country have either just switched or are switching or will soon switch to chloramines.
CURWOOD: So, the potential is quite large.
EDWARDS: The potential is there for a catastrophic corrosion problem costing consumers billions of dollars a year and adversely impacting the public health.
CURWOOD: Marc Edwards is a professor of civil engineering at Virginia Tech, and recently testified at a Congressional hearing about elevated lead levels in D.C.’s drinking water. Thanks so much for taking this time with me today.
EDWARDS: You’re welcome.
CURWOOD: Based on Professor Edwards’ findings, District of Columbia officials now say they will expand water testing in the city beyond the estimated 23,000 homes with lead service lines. This broader sampling could determine if corrosive water is also causing lead problems in homes with brass fittings or partial copper lines.
The controversy over Washington D.C.’s water has also pushed the EPA to call for a nationwide assessment of lead in drinking water. The EPA’s Assistant Administrator for Water Ben Grumbles says the agency needs to find out how widespread these problems might be.
GRUMBLES: We don’t see it as a national crisis at this point. I think, generally speaking, the lead and copper rule has been working well. But what we do find is on a localized basis there may be some unanswered scientific questions about corrosivity or lead service lines. So I don’t view it as a national crisis, but this is a national opportunity to look more closely at how effectively the lead in drinking water rule is being implemented.
[MUSIC: The Pogues “Wild Cats of Kilkenny” RUM, SODOMY & THE LASH (Wea International – 1985)]
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