"When you're looking up at the river, you need to expect that you're going to get wet." (unknown)
Humankind has had an interesting history with respect to water. Water, at least to outward appearances, is a pretty benign substance. If you put some in a container, it will usually just sit there and do no harm. If you pour it through a pipe, it will likewise usually go where you want it to go and do what you want it to do. The one exception is precipitation--so far, we've had no control over rain, snow, humidity, and the like. When water is in the atmosphere, it does pretty much what it wants to do.
So we humans drew conclusions from our ability to contain and channel water, and we built dams as pots to hold it, and built levees as pipes to restrict and direct it. It was sound theory, at least as we understood it at the time. It's certainly arguable that our modern civilization couldn't have existed without our dams and levees, and there's plenty of data to support that. Today, 2.3 million kilowatt-hours of electricity are generated by dams each year.
We've also put levees to good use. Levees currently prevent millions of acres from routine flooding, and countless members of our society live behind them--below water level or below flood level. And countless means countless--there is currently no data that indicates how many people would get wet if every levee failed at once. So with respect to building cities and societies, levees have been a worthwhile tool.
But oh, the cost!
I will save discussions of dams and species extinction for another day. They are certainly worth the discussion, and if you want further information or convincing in that area, see the book recommendation at the end.
But the issue here today is the failure of the levee concept. Levees have a long history of failure. The first modern failure of note occurred during the Mississippi River floods of 1993.
These failures also came dramatically to public awareness in 2005 during Hurricane Katrina, when it was clearly demonstrated that however well we thought we were able to plan for keeping water in the pipe didn't work: levees routinely overtopped or washed out, and as a result thousands of people were flooded out of their homes and had to flee, and there were many deaths. The areas behind the levees have not recovered fully to this day.
The saga continued: In 2011, intentional breaches of levees along the Mississippi were enacted to save highly populated areas at the cost of lower populated areas.
Today, we face a redo of 1993. A massive wall of water is slowly working its way down the Mississippi, overtopping levees at will, forcing evacuations of entire municipalities, leaving behind devastating damage and shattered lives, and pointing out very clearly once again that good intentions do not always end in good results.
Does this sound like a system that's working?
So what to do?
There are many ways to approach this problem. The first and probably most unsellable would be to admit we were in way over our heads (pun intended) when we built levees in the first place, and now having learned our lesson, we should retreat to higher ground and admit we screwed up. However, knowing the human psyche, we all understand that's unlikely to happen.
So our government and professional organizations have developed some valuable resources for those living behind levees. This and other similar resources are invaluable in deciding how to approach the situation as an individual, but also how to frame future urban planning efforts. If you are in the urban planning business, there's even a levee simulator program that will help you figure out what can go wrong and how to avoid it. Probably.
Winston Churchill once famously said: 'Americans always do the right thing--after they've exhausted all possible alternatives." That will likely be the way our levee discussion will turn out. We built dams and levees in an era of cheap labor, with cheap materials. This was undertaken with the right heart but incomplete wisdom. Now we have more complete wisdom, and so we need to follow that wisdom to the better answer. You, as an emergency management professional or public official, will need to figure out over time exactly what that means. Best wishes.
Recovering a Lost River: Rewilding Salmon, Revitalizing Communities. This valuable resource encapsulates the damage we've done by building dams.
It contributes to understanding the painful but necessary solution we need to pursue if we're going to make progress against The Sixth Extinction that's currently underway.
With regard to levees themselves, there are more useful titles and resources than one can read in a day--or a month. Search well. And save our civilization in the process. It's worth the effort.