Earlier this week, thanks to Southwings.org and pilot Ken Knevel, Vanishing Earth had the privilege to take a flight over the Mississippi River flood with N.Y. Times Best Selling Author, John Barry. Mr. Barry is the author of “Rising Tide: The Great Mississippi Flood of 1927 And How It Changed America” and a former member of the Southeast Louisiana Flood Protection Authority-East and the Louisiana Coastal Protection and Restoration Authority. Included below are several short aerial video clips from our flight. After the flight, we sat down with Mr. Barry for an interview:

JH: How long has it been since you’ve flown over the river?

John Barry: In a small plane? I’ve never done it. Though I always enjoy the landing in New Orleans when I’m on a commercial plane. It certainly gives you a perspective that you don’t get everyday and a chance to see all kinds of neat things like the shipping on the river. So a big thanks to you and Southwings for inviting me.

JH: But of course. Who else to take along other than the person who wrote the book on Mississippi River flooding? Have you been up or down the river by boat?

John Barry: Yes, actually I went to Memphis by boat as a matter of fact. I’ll never forget passing the NORCO refinery as it was quite an extraordinary sight.

JH: There was recent tragic loss of life because of the flooding of the Mississippi river. What happened?

John Barry: In the upper river people got caught in flash floods related to the flooding river.

JH: In 2011, I took a couple of flights over the flooding river and it was a little disconcerting to see how high the water was to the top of the levees. How would you compare the flooding we saw today compared to the flooding in 2011?

John Barry: At this point the water level is significantly below 2011. Right now, we’re talking about 1.25 million cfs. Compare that to Niagara falls which at flood is 200,000 cfs and normally it’s a lot less when Niagara is not flooding. In 2011 it was over 2 million cfs. So there was an enormous increase in 2011 as compared to today.

JH: What caused the 2011 flood? Snowmelt?

John Barry: It’s always a combination of factors. We won’t get a great flood on the Mississippi unless there is a flood on the Ohio river. In 1937 and 2011 there were two big floods on the Ohio. Caused by a combination of precipitation and snowmelt. If you remember the 2011 flood was actually pretty late, like early May, so I don’t think snowmelt had a lot of impact on that flood. That’s pretty late for influence of snowmelt. When you get floods in March or April that’s from snowmelt. By May most of the snowmelt is pretty much gone and it’s primarily precipitation. This year it was mostly just rain rather than snow.

JH: Do you anticipate that it will rise much higher than what we saw today?

John Barry: Not on this flood crest, not in terms of what has been forecast. The concern though is you already have saturated ground. When the river goes back down the natural reservoir that the river itself forms is still full, so if you get a lot of further precipitation we could get a very serious flood. Right now on the lower river from the confluence of the Ohio river all the way to the Gulf of Mexico this is a flood and something you take seriously. You check levees everyday, look for sandbars, look for slides look and look for all sorts of problems. I don’t want to minimize it but the system can easily contain the current amount of water in the river now, if operated properly. When you start getting multiple crests then things get a little dicey. According to some people at NOAA when I checked a few weeks ago, the long term forecast for the rest of Spring is fortunately not very wet so hopefully its accurate and nothing serious will happen this year. I will say in 1926 it was an El Nino year. In the spring of 1927 there was a tremendous amount of storms and you got record floods in 1927 as a result. 1 percent of the United States was flooded. The flood protection system on the Mississippi river was built to contain something like the 1927 flood. I’m not sure for certain that it would but I hope it would. In 2011 we approached the 1927 flood level but probably did not exceed it. 2011 was pretty dicey and I just assume not see that again.

JH: Who is in charge of the flood protection system on the river?

The Corps. But the levees are under the jurisdiction of local levee districts that are responsible for the maintenance and operation of the levee system. There are dozens of districts up and down the length of the river. The decision making on opening floodways and spillways is for the Army Corps of Engineers. Every levee district I know is fully professional and they know what they’re doing.

JH: What did you see on today’s flyover that was interesting to you? We went from Lakefront airport in New Orleans along the river to the Bonnet Carre spillway, up the river all the way to the Old River Control Structure, then to Morganza and down the Atchafalaya floodway to Morgan City before heading back.

John Barry: I’ve seen most of it on paper but never from the air so to me it was all fascinating. It was a lot to take in. I’ve been to the Bonnet Carre spillway when it was running full but that’s not the case today. It looks more like leakage to the lake although they do have several bays open. In 2008 and 2011, there was a tremendous amount of water going out and hopefully that won’t be the case. It really grabs your attention to see that amount of water passing through.

JH: Do you think that communities are prepared enough for a big river flood like 2011 or 1927?

John Barry: No. I don’t think most people down here take seriously enough the threat of a river flood in this part of the country. In the Midwest where the protection system is not as high level as down here they are more concerned about it and worry more about it. On the lower part of the river the protection is much greater than the upper part.

JH: What can go wrong on the lower part?

John Barry: What goes wrong is a levee break. That would be devastating.

JH: Are certain parts of the levee system in certain towns along the river more vulnerable than others?

John Barry: Well there are two things. First, a few years ago a lot of the levee system was below grade. Almost 150 miles of it, which is obviously quite a bit. And some of that is in the entire levee system on both sides of the river. It’s about 1200 to 1400 miles on both sides of the river and for 150 to be below grade that’s a hell of a lot and some of that was dangerously below grade, like 6 feet below. Fortunately, that was not great stretches of it but it only takes one spot because if the river starts pouring over any particular area that runs the risk of creating a breach because if the levee goes out it won’t be just that one stretch that is taken out. The forces will create a much, much wider breach. For example, in 1927 there were two levee breaks both of which poured probably double the flow or more of Niagara falls out of the river. And just overtopping over a narrow stretch could create something like that.

JH: When we were flying today, you talked about the potential for slides. Can you elaborate on that?

One of the concerns about a flood this early is, imagine a person is leaning against you and you also leaning on them. Then, one of you moves. What happens? The other starts to fall. The pressure of the river actually pushes against the levee and it’s a little bit like that. If the river goes down rapidly when that pressure is released you have to worry about slides in the levee. Some of that that levee will slide back into the river. If you then get another flood coming down the river before you have an opportunity to repair that then you have a weaker levee. So, when you get a flood in January like we have now, what about the rest of the year when there are potentially more floods?

JH: How great is the threat right now?

While there are some concerns at the moment there is nothing that you can’t take care of. It doesn’t seem like that much of a threat given the current levels. I don’t want to minimize that. It is a flood. I talk about cubic feet per second (cfs). One cfs is enough to cover in a day two acres of land with one foot of water. So if you have a million cfs, and there is more than a million now on the river, that’s enough to cover 2 million acres of land in a day with a foot of water. And that water is going to keep coming and coming and coming. River floods unlike hurricanes last for a long time. For days, unlike a hurricane which last a few hours. River floods last at least a few days and in some cases for multiple weeks. At least, that is, on the Mississippi river. Some floods are faster moving; on the Ohio for example they move much faster.

JH: Okay, so nothing to worry about right now but something to keep our eye on in the coming months particular rain and snow on the Ohio?

John Barry: Well, as a general rule, a little over half of the water on the Mississippi river comes out of the Ohio. That’s not to say they’re isn’t a lot coming from the upper Mississippi, the Missouri, and the Arkansas rivers. There are obviously a lot of tributaries besides the Ohio. The 1927 flood, which was the greatest flood on record, there was first a flood on the Ohio. It was not a relatively huge flood on the Ohio. What was the killer was that every other basin from the west was a record flood. That was a bit of an unusual circumstance. Particularly the Arkansas and White rivers had extraordinary amounts of water coming out of them compared to any other flood year that you could look at and research.

JH: Was it necessary to open the Old River Control Structure?

John Barry: Actually, it’s always open. The ORCS is there to constantly adjust the flow into the Atchafalaya river . By law, 30 percent of water and sediment is supposed to go down the Atchafalaya. So there is always or almost always water going through the ORCS. The question is whether to open Morganza and how much water to put down the ORCS. There is another floodway that has never been used on the west side of the Atchafalaya. As we speak the corps is considering whether to open Morganza or not. As we speak they have not yet made a decision. I they do, it still won’t be a lot of water coming down there. They have an operations manual and if the water is rising it says they need to do xyz. In the Bonnet Carre spillway, if it is 17ft on the gauge at Carrolton, one and a quarter cfs in the river and rising, then they are supposed to open the spillway. They defined it in way to try to minimize the decision making for any individual.

JH: In terms of the current situation, it doesn’t appear to be an emergency given that Morganza has yet to be opened and Bonnet Carre is not fully open. Is that a fair assessment?

John Barry: Sort of. Anytime the river is as high as it is today, it’s an emergency and certain processes have to kick into place. While there is expected to be 1.5 million cfs, in 2011 it was over 2 million. Almost 50percent more water. But 1.5 million cfs is still a lot of water, so everything needs to work.

JH: What then is the threat to us here New Orleans?

John Barry: Not a whole lot from this crest. Actually, New Orleans is probably the safest place in the entire river from a river flood because the spillway is above the city. The whole system is designed to keep not more than one and a quarter million cfs going past new Orleans. It’s fairly close to that but the other parts of the system have not yet kicked in.

JH: What about any threats from navigation? Have they curbed the amount of river traffic because of high water?

John Barry: High water is certainly a problem for navigation. That is potentially very dangerous. Also they used to have tows tying up on the levee which they are not supposed to do. I recall when I was on the flood authority one of the fights was to get the Coast Guard to enforce that because they weren’t paying a lot of attention to it.

JH: Is it a danger should an out of control ship or barge crash into the batture and could that result in a catastrophic levee failure?

John Barry: Yes, perhaps. And it’s even more dangerous in high water.

JH: Have restrictions been put in place?

John Barry: I don’t know a lot about what the triggers are for the navigation restrictions. I’m not as familiar with the restrictions because when I was on the levee board we didn’t have any jurisdiction and we were worried about things in our responsibility.

JH: You probably remember that ship lost control and hit the Riverwalk in downtown New Orleans?

John Barry: Yes. There have been multiple collisions over the years.

JH: So, to clarify, if an out of control ship hit a levee in New Orleans there is the potential that the river could then also crash through the levee in New Orleans?

John Barry: Well I tell you one thing you might rather keep that ship jammed in there until you figure out how to deal with it.

JH: So, then we are not really that safe? Do we have a false sense of security as long as we have these big ships out there under these current conditions?

John Barry: I don’t know and I’d rather be an alarmist when there is something to be alarmed about. I mean is there any risk? Yeah there is some risk.

JH: I understand but what I’ve noticed is that people don’t quite comprehend the dangers. To me it’s not just the high river or even the ships that we must be concerned about. For example, we’ve got this massive increase nationwide of oil trains passing along the rails including along the New Orleans river front. They are carrying the most explosive type of crude oil. I think about that one that exploded in Quebec, Canada and wonder what would happen if that happened along the river, especially because I live in the blast zone. And I wonder would the levee blow as well.

John Barry: Is there a greater risk in high water of a ship losing control. Yes. Is that a reason to shut down the river traffic? I’m not an expert on navigation so I prefer not to comment on that. And I’m not an expert on what you are referring to either. Having said that I don’t see any reason why they would close down the port at this time with the currents on the river as they are now. There are periods when there are risks that trigger restrictions imposed. There very well may be some in place now and I don’t know about it. But it’s not something I think about that much, to be honest.

JH: Well, I think about it a lot because I live so close to the river. And I fly over it all the time. So I’m a lot more connected to it than my neighbors are. They don’t see it because of the floodwall that basically disconnects most of the population in the city from it. I have a real appreciation of the power of it and the danger of it, especially after reading your book!

John Barry: Well, thanks. Now you’ve got me curious about it so when I get to my desk I’m going to begin looking into it.

—End of Interview—

Footage from Flight:

View of the Bonnet Carre Spillway from above the Mississippi River looking in the direction of Lake Pontchartrain. January 12, 2016. Jonathan Henderson, Vanishing Earth. Flight provided by SouthWings.org.

View of the Old River Control Structure floodgate system. Water flows from the Mississippi River into the Atchafalaya River thereby easing pressure off of the Mississippi and helping to prevent a change of course. January 12, 2016. Jonathan Henderson, Vanishing Earth. Flight provided by SouthWings.org.

View of the Morganza Spillway. Located in Pointe Coupee Parish, its purpose is to divert water from the Mississippi River during major flood events by flooding the Atchafalaya Basin, including the Atchafalaya River and the Atchafalaya Swamp. January 12, 2016. Jonathan Henderson, Vanishing Earth. Flight provided by SouthWings.org.

View of the Mississippi River at New Orleans. In addition to the Levees, Spillways such as the Bonnet Carre upriver help protect New Orleans from river flooding.January 12, 2016.Jonathan Henderson, Vanishing Earth. Flight provided by SouthWings.org.

View of Shell Oil Company’s NORCO Refinery just down river from the Bonnet Carre Spillway. Located in St. Charles Parish next to the Mississippi River, the refinery sits on approximately 1000 acres of land about 20 miles to the west of New Orleans. January 12, 2016. Jonathan Henderson, Vanishing Earth. Flight provided by SouthWings.org.

View from high above the Mississippi River in St. John Parish. January 12, 2016. Jonathan Henderson, Vanishing Earth. Flight provided by SouthWings.org.

View of ExxonMobil’s Refinery in Baton Rouge, Louisiana. Located on the east bank of the Mississippi River, it’s the fourth-largest oil refinery in the United States and the tenth-largest in the world.January 12, 2016. Jonathan Henderson, Vanishing Earth. Flight provided by Southwings.org.

Jonathan Henderson is the Founding President of Vanishing Earth.