Struggling To Contain A Rising Mississippi Floodwaters are rising to record heights in the lower Mississippi, weeks before they're expected to crest. Ira Flatow and guests discuss how engineers have boxed in the river with dams, levees and spillways, and whether human-induced climate change might bring more frequent floods.

Struggling To Contain A Rising Mississippi

Struggling To Contain A Rising Mississippi

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Floodwaters are rising to record heights in the lower Mississippi, weeks before they're expected to crest. Ira Flatow and guests discuss how engineers have boxed in the river with dams, levees and spillways, and whether human-induced climate change might bring more frequent floods.

Peter Gleick, president, Pacific Institute, member, National Academy of Sciences, Oakland, Calif.

Larry Banks, consulting hydraulic engineer, Army Corps of Engineers, former chief of water management, Mississippi Valley Division, Winnsboro, La.

Ed Link, former director of research and development, Army Corps of Engineers, research professor, Department of Civil and Environmental Engineering, University of Maryland, College Park, Md.


This is SCIENCE FRIDAY. I'm Ira Flatow.

Significant wouldn't really be the right word to describe the flooding along the Mississippi: Epic is more along the right lines, because the river is so swollen that it's breaking records set way back during the great floods of 1927 and '37.

The Army Corps of Engineers, which manages all the levees along the river, from Canada to New Orleans, is facing tough choices, deciding whose homes and farms to flood, whose to save because the big challenge for the Army Corps now, the last stand in this battle, so to speak, is whether to open Louisiana's Morganza Spillway, a flood way that, if opened, would inundate thousands of homes but prevent potentially catastrophic levee breaks along Baton Rouge and New Orleans.

How do engineers manage such sophisticated plumbing? How did the river even get this big in the first place? This hour, we're talking about rain, floods, levees, river engineered to be controlled. Could it be overly engineered? Could less flood control be better?

And how about climate change? Can we expect flooding like this more often in the future? What do you think? Our number, 1-800-989-8255, 1-800-989-TALK. You can also tweet us, @scifri, @-S-C-I-F-R-I, or go to our website at and leave comments there.

Let me introduce my guests. Larry Banks is a consulting hydraulic engineer for the Army Corps of Engineers. He's also former chief of water management at the Mississippi Valley Division in Vicksburg. And he joins us by phone. Welcome to SCIENCE FRIDAY.

Mr. LARRY BANKS (Consulting Hydraulic Engineer, Army Corps of Engineers): Glad to be here.

FLATOW: Thank you. Peter Gleick is president of the Pacific Institute in Oakland, California. That's a research institute that works on climate and water. He's also a member of the National Academy of Sciences, and he joins us from the studios of Youth Radio in Oakland. Welcome back, Dr. Gleick.

Dr. PETER GLEICK (President, Pacific Institute): Thanks for having me on.

FLATOW: You're welcome. Ed Link is former director of research and development for the Army Corps and a research professor in the Department of Civil and Environmental Engineering at the University of Maryland in College Park. Welcome to SCIENCE FRIDAY, Dr. Link.

Dr. ED LINK (Former Director of Research and Development, Army Corps of Engineers): Delighted to be here, thank you.

FLATOW: Mr. Banks, let me ask you about this decision. What decision will the Corps be making this weekend about controlling the flooding and opening up the spillway?

Mr. BANKS: Well, the situation right now is that we're monitoring all the water levels within the basin, particularly those down in the Morganza area along the Mississippi River.

We've developed a timeline to use in making decisions based on what the river tells us to do. We have an operation procedure that says we are to regulate the Morganza Floodway in order to keep the flows in the main stem of the Mississippi River below Morganza Floodway, between Morganza and Baton Rouge, at a flow rate of less than 1.5 million CFS.

And when we know that that situation is going to occur, then there'll be some decisions made as to what to do. But that's where we're at right now. We're not ready to say at this moment that we will operate the structure, or we won't operate the structure.

There is an appreciable amount of flooding occurring in the Atchafalaya Basin right now due to the waters of the Atchafalaya River, and operation of the structure would add a little bit of water to that.

And so it's a serious situation. It deserves much thought. But we will not operate the floodway just because it's there and it was designed to be operated as a floodway. We will use it only as it is necessary.

FLATOW: So if you determine that there's a potential for flooding of, let's say, downriver, like New Orleans, you will then open that up in terms of preventing that kind of catastrophic event.

Mr. BANKS: Yes, that is true.

FLATOW: So that's what you'll be waiting to see, how high the river is and whether that's necessary.

Mr. BANKS: That is correct. And it's - due to the legerities of flow and stage relationships that the river has during an event like this, it's a type of decision that you can't really decide what you're going to do a long time ahead. You have to kind of wait on the river.

And it's hard to sit here and wait on this flood crest. The tendency is to go ahead and make some decisions. But we have to make sure that we make the right decision, and we're looking at all alternatives - will be evaluated before that decision is made. And it'll be based on what the river tells us to do.

FLATOW: All right. Ed Link, you were - you used to work for the Army Corps. Tell us about how this whole levee system works in the Mississippi. It is a river that is engineered, basically, is it not?

Dr. LINK: Yes, it has been engineered for quite a long time. And the nation made a choice quite a number of decades ago to try to manage flooding by the use of levees. The other alternative would be to not use levees. But that decision is long behind us.

So the levees provide a way of containing the river in a controlled channel in an area where hopefully no losses occur. The problem with that is when the river comes up, the only place it has to go is up when there's a large volume of water.

So it's a constant analysis of how high do the levees need to be. And the big question is: Was the knowledge available when the levees were first designed adequate to cover the spectrum of conditions that the river might present in the future? And that's a big question.

FLATOW: You mean whether we expected a flood of this proportion when they were designed?

Dr. LINK: Yeah. Right. And are even higher floods, might we get higher floods in the future? Now, the river has been close to this high a number of times before, not - in some areas not this high. But the -there hasn't been an issue of overtopping of any of the mainline levees yet.

And it, you know, hopefully that won't be an issue here. I think if there's an issue with the levees, it will be seepage of water through the levees that would cause a problem, not, right now, not overtopping.

FLATOW: You mean the collapse of them by seepage?

Dr. LINK: Right, from water moving under the foundation of the levee.

FLATOW: And what parts of the river might that be most - might be most vulnerable to that?

Dr. LINK: Oh, it's - that typically happens where a levee goes over an old river channel, where there's porous material. But the levees are inspected very frequently to look for signs of that and to manage that if that begins to happen.

Peter Gleick, where did all this water come from? Why is this such an unexpected event?

Dr. GLEICK: All of the water came from where it normally comes from. It comes from nature. It comes from the hydrologic cycle. It fell as snow over the last many months in the basin. And the basin is huge.

The Mississippi, of course, is one of the great rivers of the world. It covers a huge fraction of the United States. And so there was a tremendous amount of water stored in snow in the basin, which is now melting and flowing down the watershed.

But there has also been an unprecedented intensity of rainfall in the last 30 days on top of it. So we have snow melt. We have massive amounts of water in rainfall, unprecedented amounts of water in rainfall just in the last few weeks. And all of that has contributed to the levels we're seeing now along the Mississippi.

FLATOW: You know, scientists are not willing to point to weather events as evidence of climate change. Are you willing to point to this, this massive flood as evidence of all the factors that you said, the snow melt, the incredible amount of rainfall as evidence that this might be something to expect more of in the future?

Dr. GLEICK: Absolutely. Let me put it this way: Climate science tells us unambiguously that we're changing the climate, and we're trapping more energy in the atmosphere. We know that trapping more energy will cause more extreme events and will worsen extreme events that would otherwise happen.

The way we think about this in the climate community is we call it loading the dice. We're rolling loaded dice, weighted toward more extreme and energetic weather.

We know through observation that flood frequency is increasing along the Mississippi. We know through observation that the atmosphere is holding a lot more moisture now than it did 20 or 30 or 40 years ago because of global warming.

I think the way to think about this now is not attribution. No one is saying the Mississippi floods are caused by climate change. I want to make that clear. But extreme events are unambiguously now influenced by climate change.

FLATOW: And Peter, if I hear what you're saying, you're saying that - I mean Ed, if I hear what you're saying, you're saying that these levees are not built for that kind of expectations of the future.

Dr. LINK: Well, they were built with some analysis of the uncertainty in the water levels that they would have to deal with. The questions is: Was that uncertainty well enough estimated to deal with unexpected? And I think that's a good question.

There's a lot of uncertainty in this type of analysis. The - we've had floods that you might consider to be extreme, that is, say, over a 100-year or one percent chance per year kind of level, six or seven times in the last 100 years on the Mississippi. So, I mean...

FLATOW: So that 100-year number is just a made up figure? Calling it a 100-year flood, since we've had six or seven times already...

Dr. LINK: No, I'm saying we've had water elevations along the main stem of the Mississippi that have exceeded what is calculated to be the one percent chance water elevation, the 100-year water elevation.

And it's been in different portions of the river, not the whole river, but having high water like this is - this high water is, of course, an extreme. But also another important point, along with the additional energy in the atmosphere, is land use.

We have, since 1927, there's been a huge change in the land use conditions in the Mississippi Basin. And it is. It's 41 percent of the contiguous United States. And that land use change has caused more of the water that falls on the landscape and melts from the snow to run off and get into the river channels more rapidly and aggregate more rapidly, and that creates larger floods.

So there's two factors working here. One is the potential for more extreme input of water, greater water levels. The other is the fact that that water is now getting into the channel and aggregating and flowing down the river much more quickly because of the way we've modified the landscape.

FLATOW: All right. We're going to take a break. We'll be right back after this break. Stay with us.

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FLATOW: I'm Ira Flatow. This is SCIENCE FRIDAY from NPR.

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FLATOW: You're listening to SCIENCE FRIDAY. I'm Ira Flatow.

We're talking this hour about the flooding on the Mississippi with my guests: Larry Banks, consulting hydraulic engineer for the Army Corps of Engineers; Peter Gleick, president of the Pacific Institute in Oakland, California; Ed Link, professor of civil and environmental engineering at the University of Maryland in College Park.

When we last talked before the break, Ed, you were talking about the land use. And I want to play a clip that we had from a SCIENCE FRIDAY back in 1993. You'll remember that flood back there. And we were on the air, and we have this, this audio clip from Dr. Victor Baker, who was a professor of hydrology and water resources at the University of Arizona.

And back in '93, we knew that the levees weren't going to protect certain areas from these big floods, and this is what he had to say.

(Soundbite of archived audio)

Dr. VICTOR BAKER (Professor of Hydrology and Water Resources, University of Arizona): I'm very concerned that people think that because there is a large dam in place, because there are levees, that they are protected against all floods when what really is the case is they are protected against little floods.

They are not protected against the biggest possible floods that can occur, and the reason is that society would not stand for how much it would cost to protect those people against the biggest possible floods that would occur.

FLATOW: Ed Link, that was - as I say, that was a clip from SCIENCE FRIDAY back in 1993. And you pointed out that people continue to develop and put new homes and buildings in the flood plain.

Dr. LINK: Yeah, in fact if you look at the 1993 flood and the area that was inundated, flooded, during that flood, there have been 28,000 new homes built back into that area and some 1,600 acres of new commercial and industrial development in the area that was flooded in '93.

That's a problem. That's raising risk. That's putting more assets and more people in jeopardy, and it's - that's a big issue.

FLATOW: Don't people know when they move to these - that they are moving into a flood plain, and this is the Faustian bargain that they're making, they're going to get flooded when a big flood happens?

Dr. LINK: I would think that that information is certainly available. The problem is how well it's communicated.

FLATOW: Peter, Larry? Larry, you've been out on the flood plain a long time. People understand what's happening there?

Mr. BANKS: I think people in the Mississippi Valley or that live in the Delta regions, all the way from Missouri all the way down the river, particularly in Louisiana, understand the importance of the levee system that we have.

We really, since we built this system beginning back in '27, when the Corps got the responsibility through the '28 Flood Control Act, the only real threat that we've had where some serious things was really considered was probably the '73 flood. We had a pretty good event in 2008.

The '93 flood that occurred in the Upper Mississippi was not really any kind of significant event as it passed through the Lower Mississippi River. But this event is one that is really taxing the system.

And we've got an incomplete system. It's not scheduled to be completed until - I'm not sure what the date is right now. It's 2030s or some time like that. We've got an incomplete system, and we've got a flood that's 85 to 90 percent of the capacity of what the system has to handle.

And the features of the system, the channel improvement features where we made some enlargements to the channel and some cutoffs back in the '30s and '40s, the revetment program, has kept the river large enough such that it can convey these floods, as well as support navigation, and the floodways, which is the place to put the water when you get the levee system full and the levees are all working in concert in this event.

And there's been some tough decisions that have to be made in operating the system. Nobody said it was an easy system to operate. But the system has really performed very well through this very excessive event.

FLATOW: Peter, would you agree with that?

Dr. GLEICK: Well, without a doubt the system is operating really well. Part of the problem, of course, is that the system was engineered, massively engineered, with the assumptions of the 20th century.

And from a climate perspective, the assumption that the climate was going to stay the same, that the climate we got in the 20th century was the climate that we were going to get in the 21st century. And we know that's no longer true. So that adds additional stress.

Ed made the point earlier that the flood along the Mississippi, and this is true of floods anywhere, are a combination of a lot of different things. They're a combination of the amount of water we get. It's a function of how we've designed the river. It's a function of land use and what we put behind those levees. All of those are at play on the Mississippi especially, which is so massively engineered.

Dr. GLEICK: Larry's point that this is an incomplete system, it's incomplete not just form an engineering perspective but from a management perspective. I don't think we can engineer our way out of these floods. We have to redesign the way we think about letting the floodplains expand. We have rethink development. And that's not just an engineering question.

FLATOW: It means a public policy question.

Dr. GLEICK: It's a public policy question. And it's got to be done in the context, in my opinion, of a change in climate.

FLATOW: And how would that help? What kind of suggestions are you talking about, or modifications?

Dr. GLEICK: Sure. Well, first of all, we have to work to reduce the emissions of greenhouse gases because the intensity of climate change is a function of what we do on that front.

But there are also unavoidable implications of climate. We're already going to see impacts that we cannot avoid. And in that sense, we also have to think about how to - we have to think about expanding floodplains.

We have to think about reducing the risk of development by preventing people from living right behind levees that, if they get overtopped by more extreme floods, are going to cause a tremendous amount of death or injury or damage.

We have to think about adapting to higher temperatures. There are a whole series of nonstructural things and structural things that we're going to have to think about that we haven't thought about so far.

FLATOW: Have they thought about this in other countries where they have flooding?

Dr. GLEICK: Well, of course, you know, the classic is the Netherlands where they've thought for many, many years about sea level. And they're now thinking pretty seriously about sea-level rise. But that's a good example.

Following Katrina, we rebuilt the levees in New Orleans to the same level that they had been built before. We might have strengthened them, but we didn't take into account future sea level rise. It would have been smart to have increased the height of some of those levees.

That's what I mean by we're not really thinking for future climate. We're still thinking about past climate.

FLATOW: Let's talk about that, Ed Link. Over in the Netherlands, they're working on a project called Room for the River to give the river some of its land back. Would a similar approach be workable here?

Dr. LINK: Yeah, in fact I'm on an advisory board for that whole - for The Netherlands looking at future climate change and Room for the River. It is a great concept. The Netherlands has found it to be essential because 60 percent of their country is below sea level.

And they are - have pretty much optimized their plumbing system right now, to deal with water, the water regime that they're currently experiencing. So any significant change like sea level rise and changes in the flow regime on the Rhine River are going to make a big difference to them.

So yeah, the Room for the River is a good concept, but it's also - could be very challenging. If you think about widening the levees, widening the space between the levees on the Mississippi and think about the gaining real estate easements on all of that land, that by itself may be the most challenging project.

Moving the levees back is a fairly simple thing to do - not a very inexpensive thing but a relatively simple thing engineering-wise. But the real estate might be staggering.

The - one correction. In New Orleans, the levees were designed considerably higher than they were prior to Katrina, and sea level rise was factored into that. A whole new hurricane climatology was created to define the water elevations that may exist in different locations around New Orleans.

And that, in addition to the uncertainty of that, which is considerable, was factored into the elevation of the structures along with sea level rise, along with subsidence of the area, which is a big issue in most deltas.

So those levees are considerably higher. In some cases, prior to Katrina, they were 14 feet, for example along Lake Borgne on the east side, and now they're 24 or 25 feet high. So there has been a huge difference in what's in place right now and what was there prior to Katrina.

FLATOW: Let's go to the phones. Gary(ph) in Wichita, Kansas, hi Gary.

GARY (Caller): Hi. You mentioned the '93 flood, and that was pretty big around here. And I want to reiterate what you said about earlier that we control this, basically, because the Corps of Engineers has taken this massive floodplain and decided to control it. So we can talk about climate change, but we still are responsible because we've chosen to control it.

And here in Wichita, we have a floodway that diverts the Little and Big Ark, and they go around the west side of town. The problem is it solved the problem for flooding in Wichita, but it put it downstream. It just basically sends the problem downstream.

And up in the Upper Missouri, they've dammed up the Missouri, and the consequences of that have been that it's kept some of the silt from replenishing the barrier islands down - out in the Gulf of Mexico.

And my thing would be is if we're going to control this, maybe we just have to readjust things, maybe in our floodway, because that thing almost crested - the floodway crested, and the river downtown was already full.

FLATOW: Right.

GARY: And maybe we should have had some sort of outlet for that water and a place - but also, the lakes up in Minnesota and so forth, maybe they have to be readjusted to be at a standard one foot lower, so that when we get the high snowmelt or we get these problems, that it doesn't just get shoved downstream.

FLATOW: Well, when - and thanks for calling, because that raises a point I wanted to bring up, and that is: Why is the power to control so many people's lives and so many acres and so many thousands of homes, why is that controlled by the military? Why is that not a political decision?

I mean, we're talking about General Walsh, who is in charge of every levee from Canada to Mississippi, deciding the lives of all these people. I have nothing against General Walsh, but isn't this the kind of thing we usually allow elected leaders to do and members of the government, so they could be held responsible feet that kind of thing?

Mr. BANKS: Well, in my - this is Larry Banks.

FLATOW: I know what you're going to quote me, the law from...

(Soundbite of laughter)

FLATOW: ...1927, and I'm not disputing that. I'm just saying, now, you know, 60, 70, 80 years ago - later, from when that happened, is it -might it not be a better idea, since there's so many states involved and so many communities involved that some - and people asking about upstream, downstream. Peter, Ed, Larry, why take - why leave it in the hands of one person who makes that decision?

Mr. BANKS: Well, first off, it's not one person that makes all those decisions. We have a commission that's appointed by the president with both civilian officers, NOAA and the commanders throughout the Mississippi Valley and the Ohio River Basin and the Missouri Basin. That commission makes these decisions relative to the Mississippi River and Tributaries Project.

But yes, I was going to quote the 1928 Flood Control Act, and there's numerous other acts - the '36. You can just go right on down the line. Congress addressed this flood control almost every year, and it has been the intent of Congress since that '28 act to have the Army Corps of Engineers to work this massive system because Congress can give us the resources, and we have access to resources to basically protect the valley during times of perilous flood, like what we're going through here.

So it's been the intent and the will of Congress to do that. And I think the Army has done a pretty good job in protecting the people of the Mississippi Valley through the events that have occurred over time.

Mr. LINK: Ira...

FLATOW: Well, let me just remind people. Let me just - I need to put a station ID in here, OK? So hang on one - this is SCIENCE FRIDAY, from NPR. I'm Ira Flatow, with Larry Banks, Peter Gleick and Ed Link.

Yes, go ahead. Is that Ed?

Mr. GLEICK: Yeah.

Mr. LINK: No, it's Peter.

FLATOW: Oh, Peter. Go ahead.

Mr. GLEICK: Ira, I just point out that these kinds of extreme events are dealt with by a lot of different agencies in a lot of different places. The Army Corps has responsibility on the Mississippi, but, of course, the Bureau of Reclamation has responsibility in much of the West. Bonneville has responsibility in the Pacific Northwest, TVA in the Southeast.

It is an indication that, in fact, our national water policy's pretty fragmented. There are a lot of different agencies responsible for a lot of different pieces of this. But overall, it's just true that we're not adequately thinking about have to deal with these new extremes.

Mr. LINK: The other item here is the caller made a very good point. You have to look at these types of problems from a systems perspective. You can't just look at resolving a flooding issue in one city like Wichita. You have to look at the entire watershed. You have to try to balance what's going on to not solve one problem and create another.

And the ability to do that system-wide kind of analysis is, unfortunately, has just been emerging over the last decade, and a lot of the attention that was paid in the past was solving more local kinds of problems.

And the Mississippi River is one of the few examples of where it is being managed as a system. There are few other river systems that are managed this way.

FLATOW: Mm-hmm. You mentioned, Peter, about the science and climate change and whatever that's involved in the future. Congress is now cutting budgets, and science is on the budget's - and Congress - are any of the tools that climatologists need going to be suffering in the upcoming budget process?

Mr. GLEICK: Well, I think, without a doubt, they're going to be suffering. Let me draw a distinction between the science and the policy side of this. The scientific community unambiguously understands that we're changing the climate, and that we're increasingly loading the dice, as I say, in terms of extreme events.

On the policy side, what we chose to do about that is a much more difficult political question. But recently, the budget cuts, in a sense, have started to blind us to just the kind of information that we need to prepare for these extreme events.

So, for example, NOAA has one satellite, one polar orbiting satellite that looks at extreme weather events, that monitors snow and rain and flooding, that's used for emergency response for the military, that's used for all sorts of critical things. And these satellites - this one satellite has instruments that fail over time. Congress just cut the budget for the replacement satellite.

And NOAA now says there's going to be - there's a high risk of an 18-month gap. We're not going to be able to see some of the things that we desperately need to see in order to prepare for these kinds of extreme events. It's like, you know, not only we're not taking the foot off the accelerator, but now we're being told we can't look out the window of the car to see what's coming. And I just think that's shortsighted.

FLATOW: All right. We're going to take a short break. We're going to come back and talk a little bit more about climate change, about the flooding in the Mississippi with Larry Banks, consulting hydraulic engineer for the Army Corps of Engineers, Peter Gleick, president of the Pacific Institute, and Ed Link, former director of research and development at the Army Corps, and he's a professor at the Department of Civil and Environmental Engineering at the University of Maryland in College Park.

Our number: 1-800-989-8255. You can tweet us @scifri, @-S-C-I-F-R-I. Go to our website at and join the discussion, leave your comments there.

We'll be right back. Stay with us.

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FLATOW: I'm Ira Flatow. This is SCIENCE FRIDAY, from NPR.

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FLATOW: You're listening to SCIENCE FRIDAY. I'm Ira Flatow. We're talking this hour about the flooding on the Mississippi with Larry Banks, Peter Gleick and Ed Link. Our number is 1-800-989-8255.

Larry, has the Army Corps changed its philosophy on managing the river over the years, considering the possibility of perhaps taking down some levees, allowing more minor floods, moving people away from the floodplains, as some of my guests have suggested?

Mr. BANKS: We've evaluated alternatives like that, and as we formulate projects and many of the new projects are formulated to look at things similar to that. I also looked at the Room for the River concept that the Dutch are considering. And out of those nine basic elements that they're looking at over there, we probably have implemented about six of them on the Mississippi River and Tributaries Project.

And so - but we're - we have not looked at concepts like just a full-scale moving of the levee system to widen the floodplain, because you've got to make such a drastic change from the landscape out there to get much lowering on the river. And the reason for that is because the levees are located along the high-top bank on the river. The river has deposited the materials over a span - long spans of time and created a high-top bank, and that's where the initial levees that were probably built with slave labor on a lot of them were built. And then, the levee line has just continued along that alignment. And it's away from the river.

We've got a wide floodplain. We've got a tremendous amount of wildlife and fisheries, resources within that floodplain of the river. And we don't have a system where levees are just built right up on the top bank.

Many of the cutoffs that we've built back in the '30s and '40s are - I think we had 16. Every one of them left a bend in the river that has become just a tremendous mecca for fish and wildlife, and the folks are - that live - particularly the ones down South, like me, have come to enjoy over the years. So the bar pits, borrow pits, where the material for the levees come from are on the riverside of the levee, in most instances. It's a tremendous fishing habitat.

And so we've got a floodplain that is probably unequal than the rest of the world, if you take it as a whole, as far as environmental habitat along the river or any system. So I think the system pits itself pretty well with some of the things that the Dutch are looking at.

FLATOW: Ed Link, any comment?

Mr. LINK: It is a system, and I agree with Larry that it's - it would be very difficult to move the - those structures, and, as I said before, I think the big issue is not engineering. It's real estate.

And just as we tend to have infrastructure built up right against the 100-year flood line on the FEMA flood insurance maps, you tend to have real - you have development occurring behind the levees where they are now. So there's some real practical reasons why it would be a big challenge to do that.

The Dutch are looking at a real systems approach with regard to the future over there because of the - their vulnerability, but also the threat from both sides, a threat from higher river flows for the same thing that Peter said from early snowmelt and more rainfall events on snow in the spring, and also sea level rise.

And so they have this problem of what to do about both of those. We're faced with a similar kind of problem, not nearly the order of magnitude as the Dutch.

FLATOW: All right. We've run out of time. Gentlemen, I want to thank you all for taking time to be with us.

Larry Banks, a consulting hydraulic engineer for the Army Corps of Engineers, former chief of water management at the Mississippi Valley Division in Vicksburg, Peter Gleick, president of the Pacific Institute in Oakland, and he's also a member of the National Academy of Sciences, Ed link, former director of research and development for the Army Corps and a research professor in the Department of Civil and Environmental Engineering, University of Maryland in College Park.

Thank you all for being with us today.

Mr. BANKS: Thank you.

Mr. LINK: Thank you.

Mr. GLEICK: Thank you.

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