• picture
  • picture
  • picture
  • picture
Public Radio's Environmental News Magazine (follow us on Google News)

March 12, 2004

Air Date: March 12, 2004



Changing Attitudes Towards America’s Dams / Jeff Young

View the page for this story

PART 1: TORPEDO THE DAMS? We'll explore the pros and cons of dam removal to restore river ecosystems and populations of migrating fish. It's a controversy in areas where dams still irrigate farms and power industry. In other places there’s little fuss. Living on Earth’s Jeff Young reports on the last hours of one dam in Virginia that nearly everyone was happy to see come down. Then a look at dams nationally, and our attitudes towards them, with Mark Capelli, who studied dam removal for the Aspen Institute. Capelli coordinates fish restoration for NOAA.

PART 2: We continue our conversation with NOAA’s Mark Capelli, then turn to Congressman George Nethercutt, from eastern Washington State. Dams in the Northwest, on the Snake River, generate electricity and let barges move grain to markets in Asia. Nethercutt rejects the notion that these, too, should be removed. Finally, a look back at the nation's largest dam removal to date, the Edwards Dam on Maine's Kennebec River. Doug Watts fishes the river and is watching it come back from his apartment window. (29:15)

Emerging Science Note/Changing Forests / Jennifer Chu

View the page for this story

Living on Earth’s Jennifer Chu reports that rising levels of carbon dioxide may be causing changes in the makeup of the Amazon. (01:20)

D.C. Water Woes

View the page for this story

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. (09:00)

The Secret Life of Lead / Cynthia Graber

View the page for this story

Scientists are testing meconium, babies' first stools, to try to assess how much lead transfers from pregnant mothers to their fetuses. Cynthia Graber has the latest installment of the Living on Earth series, "The Secret Life of Lead." (06:35)

This week's EarthEar selection
listen / download

Show Credits and Funders

Show Transcript

HOST: Steve CurwoodGUESTS: Mark Capelli, George Nethercutt, Doug Watts, Marc EdwardsREPORTERS: Jeff Young, Cynthia GraberNOTE: Jennifer Chu


CURWOOD: From NPR - this is Living on Earth.


CURWOOD: I’m Steve Curwood. An effort to reduce cancer-causing substances in the drinking water of Washington, D.C. is having some unintended consequences. The chemicals that are supposed to keep the water clean encourage the leaching of lead, and other cities may be having the same problem.

EDWARDS: The potential is there for a catastrophic corrosion problem costing consumers billions of dollars a year and adversely impacting the public's health.

CURWOOD: Also, bringing back nature by bringing down dams


CURWOOD: More communities are seeing more value in free running rivers over outmoded dams.

TIPPETT: We ran into all kinds of obstacles of, well, there’s no way that can come down. We need it for this, we need it for that. But this is spectacular. It’s what we’ve been waiting for 20 years.

CURWOOD: That and more - this week on Living on Earth. Stick around.


ANNOUNCER: Support for Living on Earth comes from the National Science Foundation and Stonyfield Farm.

Back to top


Changing Attitudes Towards America’s Dams

CURWOOD: From the Jennifer and Ted Stanley studios in Somerville, Massachusetts, welcome to Living on Earth. I’m Steve Curwood.

Much of America’s economic might was built by harnessing the power of water with dams. In the 1800’s the rivers of the East were used to power mills of the industrial revolution, and in the 1900’s the rivers of the West were pooled behind massive hydroelectric power generators and reservoirs of drinking water. The technology allowed new cities to bloom in the desert.

But this year, as many as 45 dams will be torn down. Twenty-first century calculus shows some dams aren’t worth the costs of repair, or the cost to migrating fish. Most of these dams are small, but the trend is having a big impact. We begin our coverage with a report from Living on Earth’s Jeff Young. He went to the Rappahannock River in Northern Virginia to witness the last hours of the Embrey dam.


YOUNG: Some 6,000 residents of Fredericksburg, Virginia, gathered on the banks of the Rappahannock for songs, speeches and flag-waving patriotism – the kind of event that usually marks a ribbon cutting or groundbreaking for new construction.

This, however, was a celebration of destruction. The Army Corps of Engineers was about to blow up one of the town’s landmark structures – the Embrey Dam. And even the person who shared its name thought that was a good idea. A. Thomas Embrey III, grandson of the man who built the dam, told the crowd his grandfather’s writings hint that he, too, would blow it up if he knew the toll it has taken on the river’s migrating fish.

EMBREY: He writes of fish so numerous that they appear, and I quote, as a mass of molten silver moving against the water of the river. I think you will agree with me that his answer would be yes, and he probably too would say, let the river run free. Thank you and God bless this great country of ours.


YOUNG: It was a remarkable display of just how much attitudes about dams have changed. Virginia’s senior senator, Republican John Warner, even found support for dam removal in the Bible’s Book of Ezekiel.

WARNER: ‘There will be a very great multitude of fish because these waters go there. For they will be healed and everything will live wherever the river goes.” So I simply say with the greatest humility, dear friends, we are acknowledging today that each of us here is doing God’s will. Thank you very much.


YOUNG: The Lord may work in mysterious ways, but Warner was more direct. As chair of the Senate's powerful Armed Services Committee he has considerable sway with the dam builders at the Army Corps, something he made clear to a Corps officer.

ARMY OFFICER: Yes sir, it will be done!

WARNER: Salute me, damnit! Thank you. I'm Chairman of the Armed Services Committee. I handle your pay and promotion, you got that?


YOUNG: Warner, an avid fisherman, pushed the Corps to find money and time to remove the Embrey, not an easy task. Taking out a 25-foot high, 700-foot wide dam took months of engineering studies and planning.


YOUNG: But it culminated in one satisfying moment.


YOUNG: Ten explosive charges sent concrete crashing down. And for the first time in 94 years, the Rappahannock made one great rush from the Blue Ridge Mountains to the Chesapeake Bay.


YOUNG: After the all-clear signal, John Tippett stood on the banks and smiled through a hundred foot hole in the dam that looked to him like a dream come true.

TIPPETT: This is spectacular. This is what we’ve been waiting for for 20 years.

YOUNG: Tippett leads Friends of the Rappahannock, a river conservation group founded nearly 20 years ago, he says, to speak for the river because it could not speak for itself. The river’s message was: get rid of the dam. But when he first floated that idea it hit a wall of opposition.

TIPPETT: We ran into all kinds of obstacles of, well, there’s no way that can come down. We need it for this, we need it for that, it’s gonna affect our water supply, it’s going to cause flooding – just so many issues that needed to be dealt with from an educational perspective. But thankfully, in the case of this river, by working things out, sitting down with officials, and reasoning through them we were able to build a level of comfort with this proposition. Because, indeed, it did make good sense once you thought it through.

YOUNG: Many residents realized the Embrey had long outlived its former uses for hydroelectric power and drinking water. Some city officials saw a safety hazard in its crumbling concrete. But Tippett says it was the river itself that really sold people on the idea of dam removal.

The region’s rivers are often dangerously polluted, but the Rappahannock is one where people boat, swim and fish with little worry about getting sick. The poster child for this was a silvery, spotted fish: the shad which swam up the Rappahannock to spawn but could only make it as far as the dam. Each spring, shad turned the water at the foot of the Embrey Dam a frothy silver of frustration. So Tippett's group decided to lend a hand.

TIPPETT: Every year we’d do a fish passage, a bucket brigade around the dam here, and we would stage about 50 to 60 volunteers around the corner of the dam. And bucket by bucket, they’d hand em around the dam and quickly try to get them in the water on the other side. And year after year as we did that, it helped raise the public awareness about the plight of this fish, the fact that this dam’s a relic and needs to go. And it’s a safety hazard as well. There are a lot of good reasons for getting rid of it.

YOUNG: Lawmakers and local officials helped haul the fish and got buckets full of reasons to remove the dam. Luckily for Tippet’s group, one of those bucket brigadiers later took charge of civil works for the Corps of Engineers. Tippett says even that famous dam building bureaucracy slowly moved to his way of thinking about the Embrey.

TIPPETT: It really is fantastic to see the Corps taking a lead in this regard. And it’s great to see that large bureaucratic institutions have the ability to change. Indeed, it’s another testament to the power of persistence and how working together with the environmental community, we can start to see changes in monolithic structures. [LAUGHS] Even the Corps.

YOUNG: When the dogwoods bloom on the Rappahannock's banks this year, Tippett will stand at the dam's remains to watch something no one has seen here for a century: a run of shad in a free-running river. And the group created to speak for the river will have just one more message to translate.

TIPPETTT: The river is saying thank you.

YOUNG: For Living on Earth, I’m Jeff Young in Fredericksburg, Virginia

CURWOOD: Many people have a dam not too far from where they live, perhaps even several of them. And maybe you’re wondering whether your nearby dam is a candidate for removal. Well, each dam is unique. It occupies its own stretch of water – serving, or no longer serving – its original purpose.

Joining me to assess the pluses and minuses of any given dam, and the challenges of removal, is Mark Capelli. Mr. Capelli studied water impoundments for the Aspen Institute and he now works for the National Oceanic and Atmospheric Administration. Mark, tell me, what are some of the reasons to tear down a dam?

Matilija Dam in Ventura, California is a candidate for dam removal. (Photo courtesy of Mark H Capelli, Southern California Steelhead Watershed Archive)

CAPELLI: Well, the most obvious reason is the dam no longer serves the function for which it was built, whether it be water supply, or flood control, or any other purpose. Dams do have a definite life span, and as dams get older their functions deteriorate. And that’s probably the single most important consideration in removal of a dam, whether it continues to perform the function that it was intended to perform.

CURWOOD: Tell me a little bit about this. You say that dams have life spans, and they have particular functions. Could you walk me through some of those functions and then tell me a bit about a dam’s life span?

CAPELLI: Sure. Well, the functions really depend a lot on the part of the country that you’re in. Out west we have a semi-arid environment here and it only rains a couple of months out of the year. So people have built dams to store water for storage and then later re-use. But all of these dams are built in watersheds that have soils that are easily eroded, and those dams over time begin to accumulate materials and sediment, so their storage capacity is diminished over time. And therefore, their water supply ability is also diminished.

CURWOOD: And out east – what are some of the reasons that dams get to be of old age?

CAPELLI: Well, dams in the East are generally considerably older, because the East, of course, was settled first. And those dams are different in a lot of different ways. They’re, first of all, much smaller. They’re often built not for water supply -- because they have a different climate there – they’re built to operate mills or other industrial purposes. And, in many cases, these communities have changed, the economies have changed, they don’t rely on the same kinds of power supplies. And so those kinds of dams simply have become outmoded.

CURWOOD: A few minutes ago we were listening to a story about the Embers Dam on the Rappahannock in Virginia. And people’s feelings about whether that dam should go or stay changed over a period of years, to the point where it wasn’t very controversial when, in fact, the dam came out. What makes the equation change for people?

CAPELLI: Well, dam removal is a fairly new undertaking, and I think there’s been a lot of uncertainty about what it would mean to have a dam removed. So, naturally, people are apprehensive about it. But once the planning has actually been done, people become more familiar and more comfortable with the idea of dam removal. And then, when they actually see a dam removed and understand what it really means and doesn’t mean, I think they develop a better sense for it.

CURWOOD: I’m just wondering how much of this change in attitude comes from people noticing the negative effects from dams – you know, the sand that doesn’t wash onto a beach, or the fish that they can’t catch anymore. How much of this dam removal movement is a function of growing public awareness of these things?

CAPELLI: Well I think it very much is. Most of these dams, of course, were built in the early part of the 20th century before we had anything like environmental review. So, many of these issues weren’t addressed when the dams were built, and it’s only later that we’ve come to understand what some of the long-term effects of building these facilities are. And by looking at dam removal, we go back and we ask what effect has this dam had? We know what the benefits are but what other effects have these dams had? And when we start to spell those out, people begin to understand that it’s a mixed picture, and the removal of dams sometimes is a way to address some of those other issues.

CURWOOD: I wonder how important fishermen are in this movement to remove dams.

CAPELLI: Well, they’re very important. And on the East coast, one of the principle motivations for removing dams is to bring back some of the fisheries that depend upon fish being able to come out of the ocean, move into these rivers and to spawn. And the spawning habitat has, in many cases, been blocked by these dams. So this is a major motivation.

CURWOOD: Let’s talk a bit about the life cycle of the dam. Over time you say that the sediment builds up in an impoundment of water which makes the dam less useful and perhaps raises the odds that it should be removed. But what do you do with all that sediment if you do decide to remove a dam?

CAPELLI: Well, the removal of the sediment is probably the biggest challenge of any dam removal that involves sediment. The dam structure itself is rather small compared to the amount of sediment that is stored behind the dam. And we haven’t had experience yet with removing a very large dam with a very large amount of sediment behind it. We’re still working out those issues. You can remove it mechanically in some way. You could sluice it, perhaps, through a pipeline mixed with water. Or you could remove the dam in a gradual fashion and let the river itself do the work, washing down the sediment downstream and ultimately to the ocean. But the exact approach that you take will vary from dam to dam and the amount of sediment, the kind of sediment, the condition of the sediment, and so on. But it’s clearly the single biggest challenge we have – removing dams that have a lot of sediment stored behind them.

CURWOOD: We’ll have more about the challenges and benefits of dam removal with Mark Capelli in just a moment. We’ll also hear from a Congressman about why he wants to keep several large dams operating in the Pacific Northwest. And a look back: five years after the biggest dam removal to date, in the state of Maine. Keep listening to Living on Earth.

[MUSIC: Vangelis “Theme from Antartica” ANTARCTICA SOUNDTRACK (Polygram Records – 1983)]

CURWOOD: Welcome back to Living on Earth, I'm Steve Curwood and my guest is Mark Capelli of the National Oceanic and Atmospheric Administration. We’ve been talking about dams, and the difficulties of removing large river dams once they've been deemed obsolete. Mark, give us some specifics, if you will. Tell us about the Matilija Dam near you in Ventura County, California.

CAPELLI: The Matilija Dam was built by the County of Ventura, originally as a water supply. But it was built in a location where the rate of erosion is extremely high, so the dam has rapidly filled up with sediment. It’s almost 90 percent full now. It originally had a capacity of about 7,000 acre/feet, now it has a capacity of less than 500. So that’s a 90 percent reduction. And that’s one of the reasons there’s this strong interest in taking this dam down. It can’t just sit there filled with sediment. It becomes a white elephant around the neck of the local jurisdiction. It’s also a dam that’s had a major impact on the steelhead runs in the Ventura River. It’s blocked one of the principle steelhead spawning and rearing areas. So the removal of the dam would open those areas up for steelhead, and contribute in a significant way to the recovery of the steelhead runs in the Ventura River.

Steelhead taken from the Ventura River before the construction of the Matilija Dam in 1946. (Photo courtesy of Mark H Capelli, Southern California Steelhead Watershed Archive)

CURWOOD: Sounds like you think it would be a pretty good idea to take this dam down.

CAPELLI: Well, most people do who’ve looked at this. It has widespread support across the board for removal. A lot of people are also looking at it as an important demonstration project, of just how you go about removing a dam that’s very large – it’s approximately 200 feet high. It would be the largest dam removed in the U.S. to date. It’s also a dam that has a very large amount of sediment stored behind it, around six million cubic yards. So, it’s an important test case in just how you go about decommissioning and removing a structure of this size.

CURWOOD: What are you going to do with all that sediment if it comes down?

CAPELLI: Well, we’ve not completed the planning on this, but what we’re looking at is using the river itself to transport the majority of the sediment into the ocean.

CURWOOD: So, every time there’s a lot of rain or something it could move out some more sediment.

CAPELLI: Exactly.

CURWOOD: It might take you a number of years to do it that way.

CAPELLI: It’ll take a number of years, but it could also happen very, very quickly. If we are to go into a wet cycle like we were in the late 90s, a good part of that sediment could be removed within ten years.

CURWOOD: Out in the West I would think that there are some sediments that would be loaded with toxic substances such as arsenic and copper, if the river has been running through a mining territory. And I’m wondering, how could you remove a dam if it would then release tons of contaminated sediment into a waterway?

CAPELLI: Well, one of the first things that you have to do when you’re looking at a situation where there’s lots of sediment is, of course, do some very, very careful testing of the sediments. It may be that the pollutants or the toxic materials are just located in a portion of the sediment -- in a layer or in an isolated pocket. So, you could deal with it in that way. If the material is distributed throughout the sediment and you can’t really allow it to go downstream, then what you may want to do is excavate a channel through the sediment, remove that mechanically, and then stabilize the rest of the sediment.

CURWOOD: It sounds like it costs a lot of money to remove a large dam.

CAPELLI: Well, the removal of the dam structure itself is actually fairly cheap. It’s the management of the sediment that can be very expensive. And again, that’s going to depend on how much work you’re going to let the stream do, versus how much you’re going to do mechanically.

CURWOOD: How often is it cheaper to take down a dam than to rebuild it to make it work correctly?

CAPELLI: It’s hard to generalize, but what we have found to date is that the rehabilitation of an old dam to meet current standards is, in fact, very, very expensive. These are facilities that naturally age. It’s like a highway – if you don’t maintain it, it doesn’t maintain itself. People didn’t build dams with that in mind, though. And so, unlike a lot of infrastructure – whether it be highways, or sewage treatment plants, or water treatment plants – there really aren’t strong maintenance programs in place for dams. Dams, I think, because they work so simply, invited simplistic thinking. And it’s only been in the last ten or 15 years that people have suddenly realized, oh, this dam isn’t going to maintain itself in perpetuity. Just like a car, or a house – if you let the termites go in a house too long, pretty soon it’s not really fixable. It’s a tear-down. And maybe you don’t want to build there after all.

CURWOOD: Mark Capelli is a fish recovery coordinator with the National Oceanic and Atmospheric Administration. Thanks so much for taking this time with me today.

CAPELLI: You’re quite welcome.

CURWOOD: Now we turn to Republican Congressman George Nethercutt of eastern Washington State, where many farmers irrigate their crops with water pulled from behind dams on the Columbia and Snake Rivers, and where dams provide inexpensive electricity – a lot of it – and slow the Snake River for important barge traffic. Welcome, Congressman.

NETHERCUTT: Thank you, happy to be with you.

CURWOOD: Let’s create a map now for people, in their mind’s eyes. The Snake River is born really in the Rockies, isn’t it, in Idaho?

NETHERCUTT: It is. And it comes down and meets with the Clearwater River from Montana and Idaho and then travels westerly along the southern tier of my Congressional district, and then on and meets up with the Columbia River, which then goes on into Portland and Vancouver and exits there to the ocean. So it’s a long, meandering river system that goes across a lot of farmland and a lot of open space. And Columbia and Snake kind of bisect my Congressional district and the state of Washington.

CURWOOD: And it’s the power of the Snake River falling out of the Rockies that made it so attractive, I guess, back in the 60’s as a source of electric power. It must generate plenty of electricity right up to the present day in your district there in eastern Washington.

NETHERCUTT: Yes, sir, it does.

CURWOOD: Tell me about these dams and how they’re viewed there.

NETHERCUTT: Well, the dams are viewed by those that are closest to them with favor. They provide, as you said, inexpensive and clean and renewable energy. They provide irrigation and some flood control. They provide transportation, they provide recreation, and they provide healthy salmon runs. And so, based on the attitudes of people in the state of Washington, primarily the eastern side of the state but also on the western, the population is glad that the dams are there. They’re providing cheap, inexpensive, and clean, renewable energy sources. And, otherwise, they provide commercial opportunities to the people in the region.

CURWOOD: Now, I’m thinking that these dams turn what would be swifter flowing, rather shallow rivers into a series of deeper, more still bodies of water that are of course good for huge barges of grain. And I guess what, that grain goes to the Pacific and to customers, what, on the other side of the Pacific Ocean, I imagine?

NETHERCUTT: Literally around the world. We export about 80 to 90 percent of all the grain products we grow. We grow soft, white wheat, some of the purest and best in the world. We grow peas and lentils, potatoes. We have 250 crops that are born and raised, I’ll say, in the state of Washington. So, it’s a high and a heavy and a productive agricultural economy for our state.

CURWOOD: Now, there are some conservationists who argue that those four dams on the lower Snake River, in particular, that are so sensitive involving the salmon runs, they’re going to have to come down if salmon really are going to be able to reach up into that part of the river. What’s wrong with their analysis?

NETHERCUTT: Well, it ignores the cost, both to the salmon populations and certainly to the economy. It ignores the fact that the cost just to remove the dams is estimated to be one and a half billion dollars. And so I think they’re ignoring the economics of the situation. And they’re ignoring the consequences to the fish, and to the environment.

These are low cost, inexpensive, clean, renewable energy sources. I mean, hydropower is renewable, it’s clean, it’s as clean as you can get. And so what do you replace the energy load with? Is it fossil fuels? What do you do with the barge traffic that now takes the grain from farm to port and to market? It’s estimated that there would be 700 thousand diesel trucks that would be on the road barging – I should say transporting – that grain that is now barged down the river.

So from an environmental standpoint, from a cost standpoint, from an economic standpoint to the region, from an environmental standpoint, it’s a negative if you take those dams out. Because the people of our region have to have the power that goes with it. In fact, those dams will power a city the size of Seattle. So we have to replace that with something. And that’s certainly going to be anti-environmental to do the alternative.

CURWOOD: I want to thank you, Congressman.

NETHERCUTT: Thank you very much for having me.

CURWOOD: Perhaps the most famous dam removed to date in the United States was the Edwards Dam on the Kennebec River in Maine in 1999. Doug Watts is a fisherman and activist with Friends of the Kennebec. He watched the Edwards Dam come down from an apartment he rented overlooking the river. Hey, Doug, you there?

WATTS: Yeah, Steve!

CURWOOD: Where were you when this dam first came down?

WATTS: I was across the street.


WATTS: Because that’s where I live.

CURWOOD: How are people using the river differently now that the dam, the Edwards dam, is down? Does it get a little crowded out there sometimes on the weekends?

WATTS: No. Actually, it was a lot more crowded when the dam was in because all the fish, the striped bass and the other fish, would essentially come right up to the dam and get stopped there, and the bait fish would get stopped, the alewives. So there was a traffic jam right around the dam and so all the fishing was concentrated in a pretty small area. And actually it became difficult to fish because everyone was crossing each other’s lines. And now, instead of having about a half a mile of river to fish below the dam, now there’s 20 miles up to the next set of dams in Waterville. So now there’s plenty of elbowroom. In fact, some people complain that now the fish have the advantage.


WATTS: Because before it was like shooting fish in a bucket because they were all jam-packed right below the dam. Now, they’re everywhere, they’re all over the place. And it’s actually for me, fishing – it’s actually harder fishing now because now the fish have the advantage, they can pretty much go anywhere they want. It takes more skill as an angler now than it did before. Before you could catch 60 stripers in two hours because they’re all packed into a pretty small area.

CURWOOD: So, it’s more of a sport these days?

WATTS: Oh, yeah. The other thing, too, is that once the dam came out and the river went back to its natural channel, natural gravel bars, no one had ever seen it before. So it was totally new territory. So as someone who is fishing, it’s like going to a lake that no one’s ever been to, ever. And you have to sort of figure it out from scratch.

CURWOOD: How do the fish figure this out? I mean, the anadromous fish like the salmon and the shad and such that go back up stream to spawn – they’re supposed to go back to where they were born. What do they do in this case?

WATTS: Actually, watching how the fish have reacted to this has been one of the most interesting things. Because a lot of people said just what you said, that these fish have been confined below this dam now for 150 years, and are they going to have an instinct in them which is going to say go up stream? And literally, as soon as the next spring came -- when the salmon, the shad, the alewives, the sturgeon, the stripers, they all came in and began their migration -- they just went right past the dam site and continued upstream, some of them. Some of them didn’t go upstream. Some of them stayed down around here, some of them went all the way up to the next set of dams, some of them stopped halfway. I think what’s happening now is that the fish have a really big selection of habitat. And now they’re able to choose the habitat that, in their opinion, is the best for spawning.

CURWOOD: Tell me about the insects there in the river. How did those change?

WATTS: Well, one of the things we learned from some of the consultants that worked on trying to predict what would happen with the dam removed is that – it was an education for me – is that the food web of a river starts with the algae that makes the rocks slippery. It’s called benthic algae.


WATTS: The aquatic insects eat that stuff, and the aquatic insects essentially form the base of the food web for juvenile fish and adult fish. And when the dam was in place, the sunlight couldn’t penetrate to the bottom because it was too deep. So there wasn’t food for aquatic insects. As soon as the river went down to its natural level - and most of it’s between five and ten feet deep – that essentially is perfect habitat for algae which the insects eat. And then everything else eats the insects – songbirds, swallows, flycatchers, kingbirds, and bats. And that’s what the fish eat, the baby shad, the baby salmon, baby bass. Everything is eating bugs. And by removing the dam and restoring 20 miles of really nice big river habitat, we created a bug factory.

CURWOOD: Now there are still plenty of dams on the river. Where are they and what’s going to happen to them?

WATTS: There’s a lot of dams on the river, just like there are on every river in New England, every large river in New England. The Edwards Dam was at the head of tide, which in terms of sea-run fish is the absolute worst place you could ever put a dam.

CURWOOD: What’s the head of tide?

WATTS: That’s where the tidal influence stops.

CURWOOD: It goes all the way from the ocean up to Augusta, Maine.

WATTS: Yeah, it’s fresh water but we still have a four-foot tidal effect in Augusta. Below here it’s more of a deeper – it’s more of an estuary, which is a nice nursery are for fish, but they have to get above the head of tide to spawn. And now with Edwards out we’ve got a 20 mile run of river above the head of tide, which, for the next few decades, is big enough to allow these fish stocks to come back, at least to regain a foothold so they’re not almost going extinct. So I think that gives us time – and I say us, I mean people – gives people time to consider what the options are going to be for the next 20 years. It’s quite possible that in 20 years people are going to say, you know, maybe we should get rid of some more of these dams. Maybe they won’t.

CURWOOD: Doug Watts is the director of Friends of Kennebec Salmon. We reached him in Augusta, Maine. Thanks so much for taking this time with me today.

WATTS: Thank you, sir.

Related links:
- Virginia Dept. of Game & Inland fisheries
- Matilija Coalition
- Matilija Dam Removal Feasibility Study

Back to top


Emerging Science Note/Changing Forests

CURWOOD: Just ahead: how an effort to protect the public from cancer-causing agents in water went wrong. First, this Note on Emerging Science from Jennifer Chu.

CHU: For fauna and flora deep in the Amazon jungle, life has gone relatively undisturbed for centuries. These rainforests are among the most bio-diverse areas in the world, and home to more than 5,000 species of trees. But new research suggests the composition of these trees is changing. And the catalyst for this change may be rising levels of carbon dioxide, from industrial emissions around the world.

Scientists in Panama have seen what they call a dramatic change in the makeup of the forest. For the last two decades, they’ve studied 14,000 trees in the central Amazon. As they compiled their data, several trends caught their eye. The first is that most tree species began growing faster than normal. Second, there appeared to be a high turnover of old trees to younger saplings. And finally, and most surprisingly, larger, faster-growing trees seemed to be taking over areas where smaller, slower-growing ones would normally thrive.

Researchers worry that this carbon dioxide overload could decrease biodiversity by accelerating competition among trees. There could also be global implications. Forests are known to cut down the greenhouse effect by storing up carbon in tree roots. The smaller, denser trees that have more carbon capacity could lose out to taller, more competitive canopy species. Down the line, scientists also suggest that as the composition of the forest changes, so might the animals that live in it. That’s this week’s Note on Emerging Science, I’m Jennifer Chu.

CURWOOD: And you’re listening to Living on Earth.

ANNOUNCER: Support for NPR comes from NPR stations, and: Aveda - an Earth-conscious beauty company committed to preserving natural resources and finding more sustainable ways of doing business. Information available at Aveda.com; The Noyce Foundation, dedicated to improving Math and Science instruction from kindergarten through grade 12; The Annenberg Foundation; and, The Kellogg Foundation, helping people help themselves by investing in individuals, their families, and their communities. On the web at wkkf.org. This is NPR, National Public Radio.

[MUSIC: The Pogues “A Pistol for Paddy Garcia” RUM, SODOMY & THE LASH (Wea International – 1985)]

Back to top


D.C. Water Woes

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)]

Related link:
D.C. Water and Sewer Authority

Back to top


The Secret Life of Lead

CURWOOD: Lead is not only a problem in drinking water. Though lead paint in American homes was outlawed in the 1970s, it is still present in older homes, and it is still putting pregnant women and children at risk. For the past year, Living on Earth has been following the work of researchers who look at ways lead can affect children, including lowered IQ, impulse control problems, and juvenile delinquency. These scientists are examining the ways children might come in contact with lead in their homes, particularly when they’re toddlers. And there’s another question they hope to answer – how much lead passes from a pregnant mother to her fetus? Living on Earth’s Cynthia Graber has this latest installment in our series, “The Secret Life of Lead.”


CALLAHAN: Should we change your diaper? I know that’s not a problem. What’s the matter, huh?


GRABER: Stephanie Callahan sits in her living room and jiggles her newborn daughter Kylie Renee on her lap. Callahan and her 11-day-old baby are part of a three-year lead study run by Cincinnati Children’s Hospital and the University of Cincinnati. Scientists want to know how low levels of lead affect children, and figure out how to clean up the home environment.

In this part of the study, the researchers are trying to determine how much lead transfers from the mother to the baby in utero, and they’re hoping meconium can help them figure it out. Meconium is the greenish, tarry substance that makes up a baby’s first stools. It’s not actually fecal matter. Instead, it’s made up of bile, mucous, parts of the baby’s intestines as they hollow out, and substances from amniotic fluid.

As a new mom, Stephanie Callahan played a crucial role in this study, making sure her baby’s first dirty diapers didn’t end up in the hospital trash.

CALLAHAN: So, it was kind of weird. I felt awkward hitting the call button, not saying I need pain medicine, or I need this … Um, I got a dirty diaper, you need to come get it [LAUGHS].

GRABER: These dirty diapers, with up to a quarter cup of meconium, are now frozen and stored in Cincinnati. Once the first hundred mothers in the study give birth, the babies’ diapers will be sent to the Centers for Disease Control in Atlanta where the meconium will be analyzed.


GRABER: At a CDC laboratory, chemist Dana Barr and a lab technician use a meconium sample to demonstrate their research methods. Barr says while testing blood or urine allows scientists to evaluate what the baby has been exposed to recently, her hope is that meconium will show what the baby has been exposed to over many months.

Dana Barr and lab technician Donny Whitehead.

BARR: And since meconium starts accumulating in the bowels of the infant right around 12 to 14 weeks gestation, and it continues to accumulate throughout pregnancy, you’re theoretically getting everything that could possibly be deposited into that meconium over that period of time. And so, you perhaps can look at exposure over the last two trimesters of pregnancy.


GRABER: The lab technician mixes the meconium with a blender-like instrument to make sure chemicals and cells are distributed evenly throughout the sample. Barr says the device is a miniature version of something you’d find in the kitchen.

BARR: A lot of the techniques we use in the laboratory are very analogous to cooking things.

GRABER: The technician carefully measures out a half gram of meconium and then adds a solvent, such as methanol or methylene chloride, which is designed to extract various chemicals from the substance.

BARR: If you were preparing a chicken stock, for instance, you would want to make sure the chicken was fully immersed in the water, and that you boiled it and you let it sit in that water for a long time. We’re doing the same thing here. We’re trying to get some of the – not the stock out of the chicken here, but we’re trying to get the chemicals we want to measure out of the meconium. And so it’s really important to mix it together and let it sit together for a while before we take off the solvent layer.


GRABER: The mixture then goes into a centrifuge so the liquid solvents that now contain the chemicals separate from the gooey meconium.

BARR: The part I’m about to show you is the part that makes our lab really unique.


GRABER: Barr walks to another room, which is filled with large beige pieces of equipment. Small robotic arms on one machine pick up tiny vials filled with liquids to be analyzed. This expensive equipment can detect and analyze miniscule amounts of chemicals.


GRABER: Studies from all over the country send samples here for testing, including a biomonitoring project looking at toxins in breast milk that was recently featured on Living on Earth. In this study, researchers aren’t only testing for lead. They’re also checking levels of pesticides, and of mercury. Like lead, these all are neurotoxins and can affect a baby’s development. Barr says she is now in the process of determining which solvents will best separate lead and the other neurotoxins from the Cincinnati meconium.

Chemist Dana Barr of the CDC.

BARR: You know, it’s a part of the research process. And it takes time, often. Sometimes you’re very successful on the first few attempts. And really the development is not the arduous process. We know enough about the chemicals that we can easily develop it. It’s validating and make sure it’s a rock solid method before we apply it to the samples. That’s the part that takes a long time.

GRABER: At Case Western University in Ohio, Cynthia Bearer is the primary researcher on the lead and meconium study, collaborating with chemist Dana Barr. Bearer pioneered using meconium to check how many alcoholic drinks a mother consumed during pregnancy – an important quantitative move beyond just examining whether the mom had been drinking at all. Until then, scientists studied meconium to determine whether or not the mother had used illegal drugs. In her research, Bearer began with alcohol as a type of test case for studying environmental neurotoxins because both alcohol and these toxins affect the developing brains of fetuses.

BEARER: But you can ask a woman how much alcohol she’s had to drink and get some idea of what her exposure has been, whereas with a lot of environmental toxins, that’s very difficult to do. So I used alcohol as setting up a system for, hopefully, that I could apply for environmental toxins.

GRABER: Bearer hopes her research will eventually lead to routine meconium tests in hospitals. She says right now, newborns are given a blood test and the babies that test positive for rare genetic diseases can receive medicine or dietary changes that will help them lead normal lives.

BEARER: And if we had some way of screening newborns for exposures that were occurring in their environment, and we had these interventions where we could modify their environment so they weren’t exposed anymore, or we could intervene with some of these early learning paradigms, then we could improve their outcomes, too. We can improve these kids’ outcomes, and we’re not doing that now.

GRABER: If analyzing meconium proves successful as a measure of babies’ exposure to neurotoxins in utero, the next step is to determine what effect these levels have. And for the next three years, as the babies grow, members of the research team in Cincinnati will monitor their development. For Living on Earth, I’m Cynthia Graber.

Back to top


CURWOOD: And for this week, that's Living on Earth. Next week, the Bush Administration says fish farming should be vastly expanded -- and the place to do it is the deep ocean. The plan is drawing praise from some, but others say the economics are out of whack.

PAULEY: It can feed a niche market, but it cannot feed humanity.

CURWOOD: Deep ocean fish farming – next time on Living on Earth. And between now and then you can hear us anytime and get the stories behind the news by going to livingonearth.org. That’s livingonearth.org.


[Earthear: “Central Valley: Freshwater Marsh” QUIET PLACES: A SOUND WALK ACROSS NATURAL CALIFORNIA (Oakland Museum of California)]

CURWOOD: We leave you this week knee deep in a freshwater marsh.


CURWOOD: These are the sounds of the many avian inhabitants and visitors of the wetland areas that dot California’s Central Valley as recorded for the California Library of Natural Sounds.


CURWOOD: Living on Earth is produced by the World Media Foundation. You can find us at LivingonEarth.org. Our staff includes: Nathan Marcy, Susan Shepherd, and Tom Simon. Nal Terro engineered this program with help from Paul Wabrek, Stephen Belter and Al Avery – who also runs our website. Our intern is Christopher Bolick. Special thanks to Ernie Silver. Alison Dean composed our themes. Environmental sound art courtesy of EarthEar. I’m Steve Curwood. Thanks for listening.

ANNOUNCER: Funding for Living on Earth comes form the National Science Foundation, supporting coverage of emerging science; and Stonyfield Farm – organic yogurt, cultured soy, and smoothies. Ten percent of their profits are donated to support environmental causes and family farms. Learn more at Stonyfield.com. Support also comes from NPR member stations and the Annenberg Foundation.

ANNOUNCER: This is NPR, National Public Radio.


Living on Earth wants to hear from you!

Living on Earth
62 Calef Highway, Suite 212
Lee, NH 03861
Telephone: 617-287-4121
E-mail: comments@loe.org

Newsletter [Click here]

Donate to Living on Earth!
Living on Earth is an independent media program and relies entirely on contributions from listeners and institutions supporting public service. Please donate now to preserve an independent environmental voice.

Living on Earth offers a weekly delivery of the show's rundown to your mailbox. Sign up for our newsletter today!

Sailors For The Sea: Be the change you want to sea.

Creating positive outcomes for future generations.

Innovating to make the world a better, more sustainable place to live. Listen to the race to 9 billion

The Grantham Foundation for the Protection of the Environment: Committed to protecting and improving the health of the global environment.

Contribute to Living on Earth and receive, as our gift to you, an archival print of one of Mark Seth Lender's extraordinary wildlife photographs. Follow the link to see Mark's current collection of photographs.

Buy a signed copy of Mark Seth Lender's book Smeagull the Seagull & support Living on Earth