Elegant Figures

Building in a Flood Plain, and a Map of the Flood of 1927

May 20th, 2011 by Robert Simmon

In response to Map of the Ancient Mississippi a few of you left comments to the effect of “no one should live in floodplains.” It’s an appealing notion, but I think it’s unrealistic. Anne Jefferson of Highly Allochthonous published an epic post yesterday outlining the benefits and risks of building in a flood plain, and the need to balance them: Levees and the illusion of flood control. It’s well worth a read. Plus, she dug up some great archival imagery, like this map of the 1927 flood:

Mississippi River Flood of 1927 Showing Flooded Areas and Field of Operations.

Some additional details on the map are in this article from the National Archives: The 200th Anniversary of the Survey of the Coast.

14 Responses to “Building in a Flood Plain, and a Map of the Flood of 1927”

  1. Peter Curia says:

    I still believe that people and structures do not need to be in flood plains. There is plenty of land (or build UP) available.

  2. ana berger says:

    I live on the coast of the “Rio de la Plata” in Buenos Aires. Do you know of any studies or predictions on floods due to global warming in near future?Thank you.

  3. Eliza says:

    Peter, with all due respect your idea is not well thought out. The Mississippi floodplains are too large to live outside of and farm or work on. The daily commute for every person whose job relies on these fertile floodplains or commerce along the river would tie up every little country road that travels east or west away from the river. The required infrastructure investment would overwhelm the federal and local resources available to maintain streets and bridges. What marginal farmland would you like to see pushed into production to make up for the millions of acres of highly-productive farmland and forest land that would have to be abandoned?

  4. Robert Simmon says:


    Unfortunately, I do not.

  5. D Sellers says:

    I have no problems with people living in dangerous areas, since they get building permits from politicians who have no conscience.
    I do, however, have a real problem if they can tap federal funds to rebuild. Do they have insurance? If not, why not? Because it is too expensive? How much more of a clue do they need?

  6. Jay Sims says:

    Yes we must use the floodplain and guarantee folks whose livelihoods come under fire that they can rebuild because that production we depend on!

  7. Eliza says:

    D- Yes, most farmers do have crop insurance. They pay in every year, just like you do for your car or your house. THe ones who don’t have crop insurance are facing a loss this year.

    Jay- I’m not sure if you are being sarcastic, but I suggest you calculate the amount of acreage that is in the floodplains of the Ohio-Mississippi-Missouri river system and propose a replacement for the timber, grain, and produce that comes off of those acres. I think you will find that federal flood insurance programs are much cheaper than the increased cost of living the United States would incur.

  8. Robert Simmon says:

    Folks: U.S. flood control policy is a complex and contentious subject that’s well outside my area of my expertise, and beyond the purview of this blog. Please keep the discussion focused on design and visualization, like marveling at the skill of the cartographers who drafted the flood map above 80 years ago, without the aid of computers, satellites, or GPS.

  9. Heather Ernst says:

    This map is very detailed and clear for having been done 80 years ago without the help of modern technology. It details the path of the river, what levees broke in what direction, and more. I can only imagine the devastation by seeing how many red cross camps there were along the river. Absolutely phenomenal map. It must have taken a massive human effort to create this map and they did a great job.

  10. Robert Simmon says:

    Heather: I have a pet theory that information technology has led to poorer maps and graphs. The majority of people making visualizations (and those writing the software) have little or no training in design or graphics. Before computers, the only people who could make visualizations were experts. There’s no real way to prove it, of course, but I’ll have to dig up some of the superb diagrams I’ve seen from NASA’s Apollo days.

  11. Heather Ernst says:

    …I cannot understand how the government believed that enclosing the Mississippi River in levees would protect the inhabitants in the flood plains. In the 1927 flood levees broke in 145 places, causing widespread destruction. Anne Jefferson is completely right that levees create an illusion of safety, and I think it is really sad that people do not understand that it is an illusion. Going back to the dangers of living on a flood plain, many people do not even know what a flood plain is, let alone if they live in one. If they did, surely they would have sense enough to NOT live there or at least have flood insurance. The truth is that people are led to believe that they are safe where the government allows development, but this is not the case. We cannot control nature, no matter how we try. If people are going to live in floodplains, which they will continue to do, then they should at least know what they are getting themselves into. I’m not saying that the information isn’t out there, because it certainly is, but this information should be provided by the realtors or some government body.

  12. Heather Ernst says:

    RS: I couldn’t agree more. Technology, though it has some benefit, has pretty much made us fat, lazy, and stupid. We dont have to think because a computer does it for it. Pretty disappointing. We believe we are so advanced, but in reality we have forgotten the skills that brought us here. This is generally speaking of course, not everyone is a “compuke” (my grandfather’s term for those who only put out information that has been put in). Harsh, but true.

  13. I love my king says:

    I want to know more about Thailand . I am living in Bangkok . I’ve heard about prediction that Bangkok will be sink again from flood in 2012 .

    Should live in Bangkok or move to the north of Thailand in 2012 ?

    Thanks anyone who will answer my question .


  14. Robert Simmon says:


    Unfortunately, I don’t know anything about forecasting flooding in Thailand, so I can’t give you a meaningful answer.