Thursday, May 30, 2013

How to Totally Eliminate Flood Damage

May 30, 2013, 10:45 a.m.

Water Will Have Its Way
If we continue to build on flood plains, we can expect continued destruction. To stop this, we need to remove structures from flood plains or we need to better tend the uplands so that they can limit flooding. Today, we instead work on the theory that we can use both flood plains and uplands intensively, as we wish, for maximum profit. We are paying the price.

-- Connie Mutel

My brother has a grass-based dairy farm in southeast Minnesota. . . . [A] rainfall simulator put 4 inches of rain on his hilly pastures in one hour. No water ran off. They waited four hours and applied 4 more inches in an hour, and still no water ran off. Last fall, when floods raged in southeast Minnesota, my brother's farm got 15 inches of rain overnight. Area corn and soybean fields were destroyed by erosion, and whole towns got washed out. On his farm, there was virtually no sign of erosion.

-- Francis Thicke

Note: Since this blog essay was posted May 30, 2013, there have been a number of opinion pieces by others coming to similar conclusions (as there have been over the years). Rather than embed them here, they have been made available as a "page."

There are three simple rules that, if followed, would totally eliminate property damage from floods:
1. Don't locate homes and other structures in flood plains.

2. Don't locate homes and other structures in flood plains.

3. Don't locate homes and other structures in flood plains.
Actually, it's a little more complicated than that -- but not by much. Water will have its way. We can dam it, we can channel it, we can sandbag and barricade our buildings, but we can't (at least not yet) control how much or where the rain falls, and how much property damage overflowing rivers (and overflowing reservoir spillways) can do to structures in a flood plain.

We can (and do) argue about what is causing "climate change," but few still argue about whether we're experiencing it. Someone reported this morning that this spring has been the wettest ever. Climate change means more unpredictable and extreme weather, more often -- droughts and floods, hotter summers and colder winters, more severe tornadoes more often, "500-year" and "100-year" floods coming every decade instead of every century.

We know the value of preventive maintenance for machinery and structures -- although we've failed to apply what we know to our nation's 600,000 bridges. We know that billions of dollars are needlessly spent on our healthcare for totally preventable conditions we've brought on ourselves, by ignoring the near-universal advice regarding dozens of diseases and conditions: weight control, diet and exercise.

I wrote about all of this the last time the Iowa River went out of its banks in 2008. It's worth repeating.

"Flooding: 'We've Found the Enemy' -- And the Answers,"
July 17, 2008

Note: Undoubtedly, although the links, below, worked in 2008, many (possibly all) of them are no longer correct. (I have made no effort to check and correct them.) A Google search may reveal that some of these documents now have other URL addresses on the Internet. If not, a library search for hard copy versions, or contacting the authors or publishers, may be your only options.

As the flood waters slowly recede, the dramatic damage emerges from the muddy water and remaining muck, and the long cleanup continues, our thoughts turn to the future.

"What did we do to deserve this?" "What's the best way to keep it from happening again?"

Thankfully, the answers to both -- coming from a diverse group of scientists and evangelicals, civil engineers and creative writers, farmers and journalists -- are coming to be more and more consistent.

Last evening my wife and I watched a DVD of Arthur Miller's adaptation of Henrik Ibsen's 1882 play, "An Enemy of the People." ["Enemy of the People (Broadway Theatre Archive)," 1966; DVD available for purchase from or by subscription from Netflix.] We'd both read Ibsen's play as college students, but had forgotten much of it (I always forgetting more than Mary). As occasionally occurs in life, Ibsen's insights and lessons from 120 years ago are as spot on as if the play had been written yesterday. Even more to the point, the setting involves a conflict between science and profit/politics regarding a community's toxic water. More I won't say, to avoid the risk of spoiling it for you. Watch it. The message is applicable to so many of the problems we confront today.

Many (including myself) wrote -- prior to our invasion of Iraq -- of what would likely happen. They were subsequently proven right. Ditto for what's wrong with our K-12 educational system. Ditto for how to deal with oil prices and our energy needs. Ditto for banks' practices regarding mortgages. Ditto for universal, single-payer health care. Ditto for campaign finance reform. And on and on.

In general, as Ralph Nader (and many others) have observed, "This country has more problems than it deserves and more solutions than it uses."

In short, as Walt Kelly famously put it in his "Pogo" comic strip, "We have met the enemy and he is us." Again relevant to our concern with flooding, though Kelly alluded to the idea in the early 1950s, the phrase was first used by him on an Earth Day poster in 1970.

The proposition is nowhere more true than with regard to flooding.

At the outset, let me acknowledge that I have no professional credentials or expertise in the flood-related areas of science. I'm simply trying to absorb what I can of the views of those who do, and pass it along, by way of this blog and in other ways, into the public marketplace of ideas.

Apparently, the one certainty is that rivers will flood. It may be every year, every 100 years, 500 years -- or even every 10,000 years -- but it will flood. We can and should reduce the severity of those floods -- and there are a number of things we can do to accomplish that. But it is folly to believe we're never going to get another flood along the Iowa River, or any other river -- especially given all the things we're now doing that tend to increase both the recurrence and the severity of flooding. [Photo credit:]

Where will it flood? In the area along any river that geologists, geographers, or engineers can identify as its "floodplain."

When we build roads, parking lots, large buildings, homes, and shopping malls in flood plains a number of undesirable consequences flow with the water. More rain water runs off, and runs off faster, and runs off with more pollutants in it, than if it fell on forests, grassland, pasture, prairies, parks, wetlands, wildlife habitats, and recreation areas -- and then worked its way through "filters" of trees and tall grasses close to the river. [Photo credit: stock footage from]

And when, up and down a river, more water is running off, and faster, and with more pollutants, the result is more floods, more often, that are more costly, and of greater severity -- as we continue to experience.

As is so often the case, retrofitting anything is ever so much more expensive than doing it right in the first place. Had we left the Iowa River's floodplain as we found it 170 years ago there would have been zero cost to this natural and virtually maintenance-free flood prevention (or minimization) program. As it is, cleaning up after this last one will cost well over $1 billion for Johnson and Linn Counties alone. And with the number of University buildings, businesses and homes involved there are very powerful political forces to deal with as well -- as Ibsen/Miller have dramatized for us.

Based on the science, what we need to do is rather obvious -- whether we take 2-5 years to get it done, or follow a longer-range (and perhaps more politically feasible) 20-50-year plan. Do we have the political leadership in place? (Yes? And just who do you have in mind?) And even if we did, does the public have the will to follow?

At a minimum, can we at least hold to a policy -- to the extent taxpayers' money is going to be provided to businesses and home owners who knowingly built in floodplains -- that such money will only be provided to those who will use it by rebuilding in a location that is not in a floodplain?

Take a look at a map of Iowa City even as late as 1930. [Click on "Remove Overlays" (to get rid of the street names), focus on the area along the Iowa River between the Burlington Street and Iowa Avenue bridges, work your way up/down to the "2m pixels" level, and then move the map north and south along the river.] Notice the open, and often forested, flood plain along the River.

Now take a look at the current "City of Iowa City, Iowa, Flood Map," showing the floodplains for "100-year floods" and "500-year-floods," and recall (or go visit to see) what we have deliberately constructed in those areas, knowing that they would inevitably flood, and knowing that, by building there, we would be increasing the likelihood, and severity, of that flooding and the dollar value of the damage those floods would cause.

From the creation of the University until well into the 20th Century our predecessors either knew enough not to put costly buildings in a floodplain or through dumb luck built on the bluffs along the River (e.g., the Old Capitol and Pentacrest, and in the 1920s the hospital and athletic facilities on the West side).

Now, as a result of decisions since, with University administrators and Regents choosing building locations that flew in the face of the science of the time (which I can't believe wasn't made available to them by knowledgeable professors), we're left with nearly a quarter-billion-dollar loss for the University's buildings alone. Erin Jordan, "U of I flood-loss estimate balloons to $232 mil," Des Moines Register, July 9, 2008 ("University of Iowa officials predict it will cost nearly $232 million to repair damage to the campus from June floods, an amount that's triple an estimate from last week.").

For a map of the forests along Iowa's rivers in the 1850s, see "1850s Landcover Map of Iowa" ("Early surveyors' notes suggested that trees covered about 6.7 million acres or 19 percent of Iowa around the time of statehood in 1846. Settlers steadily cleared the forests, however, as they grubbed out trees for cropfields, rail fences, log buildings, and lumber. By 1857, the Iowa State Agricultural Society had issued a plea calling for more careful use of timber resources."), from Iowa Department of Natural Resources, "Iowa: Portrait of the Land" (2000), entire book available as a pdf file. And see, especially, Chapter 9: "A Vision for Iowa's Land."
Would this flood have happened if we were back in the tall-grass prairie days with no tile drainage, no tillage compaction and all those wetlands diked by beaver? It is our human economics that changed the natural tall-grass ecosystem to the tilled, fertilized, pesticided, compacted and simplified condition we found in June 2008.

Would any USDA-funded riparian buffer program, or mandatory no-till planting, or even just more crop rotation with hay and pasture make any difference at the rate runoff left the land? I realize we had some heavy rains falling on saturated soils, but I also believe rain fell on a tighter, less spongy watershed upstream from Iowa City and Cedar Rapids.

The rate that water drains off tilled upland fields determines the water’s momentum energy. More momentum on tilled soil scours more soil particles along with the solubles like the fertilizer and pesticides. Though the runoff goes away, we can find it redistributed where we don’t want it — in the reservoir pools, on flooded neighborhoods and further down the Mississippi to the Gulf of Mexico.

We Eastern Iowa locals are all touched by this flood and a bit changed — but our first desire seems to be “put it back as it was” and hope that never happens again for another 500 years.

For those who are now our leaders, a new part of the job description is to protect us from the next flood, which now has a bigger dimension than imagined back in mid-June. It’s rapidly getting down to money, politics and business. Now what to do? . . .

Iowans appreciate wisdom — especially when presented in a humble, honest and “nice” way. We now need a fact-finding watershed SWAT team beyond a committee that seeks only to put it back and protect their interests. This is the time for getting the facts to understand the science underlying the root causes beyond the rain of this disaster.

Many Iowans won’t like what they hear because it means a lifestyle change — but in our guts we know that changes are needed for how we live and farm on our beloved Iowa land.

This record wet spring and resulting flood disaster provides our educable moment to “Listen to the land.”
"Louis Licht of North Liberty is president/founder of Ecolotree Inc., a company that uses poplar trees to clean up soil contamination. He’s also an adjunct associate professor in the University of Iowa Civil-Environmental Engineering Department." Louis Licht, "Flood's Message: Listen to Land," The Gazette, July 17, 2008, p. A5.

The Press-Citizen's editorial is consistent:
[P]olicymakers now need to:

o Rely more on rivers' natural floodplains rather than on levee and pump systems.

o Provide homeowners with better information about the risks of living in floodplains; and

o Provide more flood buffers by returning at-risk land to forests and wetlands.
Editorial, "Seeking Advice for Floodplain Management," Iowa City Press-Citizen, July 17, 2008, p. A11.

In the same issue, Tom Pickering says of the 2008 flood, "Mother Nature reclaimed some of the land that we altered over the years." Tom Pickering, "Restore the Wilds of City Park," Iowa City Press-Citizen, July 17, 2008, p. A11.

The paper's editorial also notes -- consistent with my earlier observations about "An Enemy of the People" and ignored advice and solutions -- that hydraulics engineering Professor Joseph Howe (father of one of my best friends and classmates at U-High) and the Iowa City Planning and Zoning Commission, warned the City Council 50 years ago not to permit home building in the Parkview Terrace area. As is so often the case, politics and profits trumped science -- and led to the predictable disasters that followed.

For more details about this political disgrace and ecological disaster, see Marc Linder, "Give land back to the Iowa River; Before the Iowa River takes back Parkview Terrace -- yet again," Iowa City Press-Citizen, July 12, 2008.

Last Sunday's Des Moines Register had two pieces also hitting consistent themes. Francis Thicke provided some pretty dramatic data regarding the impact of planting on the runoff that creates flooding:
Studies have shown that native prairie soils can absorb 5 to 7 inches of rainfall per hour. When corn and soybeans are grown on those same soils, the water absorption rate is reduced to just 0.5 to 1.5 inches of rainfall per hour. Sixty-five percent of Iowa's land area is planted to corn and soybeans. The manyfold reduction in the soil's ability to absorb rain on so many acres - in combination with extensive tile drainage to remove water from crop fields as fast as possible - makes corn and soybean cropland clearly the major contributor of flood waters to Iowa rivers during heavy rainfall.

Obviously, we are not going to return all of Iowa to pristine prairie. However, we could make some key changes in agriculture that would make a big difference in how much water soaks into the soil instead of going down the river to create flooding during heavy rainfalls.

A perennial grass and legume pasture that is rotationally grazed mimics the prairie/buffalo system that built Iowa's productive soils, and it absorbs water about as well as native prairie. My brother has such a grass-based dairy farm in southeast Minnesota. At a field day on his farm, the Natural Resources Conservation Service used a rainfall simulator to put 4 inches of rain on his hilly pastures in one hour. No water ran off. They waited four hours and applied 4 more inches in an hour, and still no water ran off.

Last fall, when floods raged in southeast Minnesota, my brother's farm got 15 inches of rain overnight. Area corn and soybean fields were destroyed by erosion, and whole towns got washed out. On his farm, there was virtually no sign of erosion. The pond at the bottom of his steep, hilly pastures did not even overflow. The soil absorbed the rain. . . .

If we could convert Iowa ethanol feedstocks from corn to prairie grass, we would make an enormous gain in reducing flooding potential. Ethanol production uses 20 percent of Iowa's corn acreage - nearly 3 million acres. Converted to prairie grass for ethanol, this large acreage would absorb five to 10 times more water during heavy rainfalls. . . .

Some will say it is too expensive to change Iowa agriculture. However, estimates of flood damage in Iowa are in the billions of dollars. If we factor in costs of soil erosion, the Gulf dead zone and other externalized costs, we might conclude it is too expensive to not change Iowa agriculture.

Francis Thicke, "To cut runoff, switch from crops to grass,"
Des Moines Register, July 13, 2008.

There was also an interview with Connie Mutel in that issue of the paper which I cannot now find online. Don't know why the Register wouldn't have uploaded it, but it doesn't seem to be there. Anyhow, here are some excerpts from my hard copy version:

[U]ntil the 1830s, Iowa had no soil erosion, no water pollution, and was covered by some of the most diverse and resilient communities [of plant and animal life] on our continent. . . .

[Today we] are discarding the soils upon which our agricultural economy is based. Our waters are among the most polluted in the nation . . .. Is Iowa being "used up" in our effort to produce food (and energy) for the world? . . .

If we continue to build on flood plains, we can expect continued destruction. To stop this, we need to remove structures from flood plains or we need to better tend the uplands so that they can limit flooding. Today, we instead work on the theory that we can use both flood plains and uplands intensively, as we wish, for maximum profit. We are paying the price.
Mike Kilen, "Author Maps Her Vision to Restore Iowa Ecology," Des Moines Register, July 13, 2008, p. OP5 (an interview with Connie Mutel).

And, of course, don't miss Connie Mutel's The Emerald Horizon: The History of Nature in Iowa (2008); and the Web site of vast resources on this and related subjects at, and Nicholas Johnson, "Greenbelts, Greenways and Flood Prevention," June 16, 2008; Nicholas Johnson, "Gazette's Flood Plan, Floodplains & Greenbelts," June 21, 2008.

And note:

Code of Iowa, Chapter 161A: Soil and Water Conservation

Division I – Division of Soil Conservation

(Sections 161A.1–4)This chapter is also known as “Soil Conservation Districts Law.” The policy of the legislature is described in Section 161A.2:

It is hereby declared to be the policy of the legislature to integrate the conservation of soil and water resources into the production of agricultural commodities to insure the long-term protection of the soil and water resources of the state of Iowa, and to encourage the development of farm management and agricultural practices that are consistent with the capability of the land to sustain agriculture, and thereby to preserve natural resources, control floods, prevent impairment of dams and reservoirs, assist and maintain the navigability of rivers and harbors, preserve wildlife, protect the tax base, protect public lands and promote the health, safety, and public welfare of the people of this state.” (emphasis supplied) Code of Iowa, Section 161A.2.

These basic truths haven't changed during the five years since I put them on this blog.

(1) The only sure-fire way to prevent property damage from floods is not to have property in flood plains -- at a minimum, just don't build or rebuild there, especially with the incentive of taxpayers' money.

(2) Instead of putting parks on the highlands, and homes and other buildings near the rivers, do the reverse -- as we have with the the Iowa City Park and Scott Park. Trying to beat back Mother Nature in order to maintain a dry flood plain just makes the flooding worse for others -- and often for ourselves as well.

By contrast, this photo shows the Iowa City Park from Park Road this afternoon. That's what a flood plain looks like. Note that not a single home or business has been flooded, just a park. Consider that, with a levee or other wall, all that water would be going downstream to cause flood damage to homes and businesses in other Iowa towns. The Park may need a little cleanup when the waters recede and evaporate, but not much, if any. [Photo credit: Nicholas Johnson.]

(3) Runoff is a major source of flood waters. Roads and parking lots don't absorb water. Trees, bushes, and grasses do. Remember Francis Thicke's story, above, about the brother's farm? Proper planting around farm fields, and in wide swaths along streams and river banks could make an enormous difference. There's a small example of this along the River bank near the old Hancher Auditorium.

Who is the enemy in our "War on Flooding"?

As Walt Kelly reminded us, linked above, "We have met the enemy and he is us."

This 45-second video shows where the "Iowa River" begins for folks living in Coralville and Iowa City: the controlled outflow from the Coralville Reservoir. The quotes are there because, since the Coralville Dam and Reservoir were built in the 1950s, it has been the U.S. Army Corps of Engineers that determines how much water will flow along the riverbed of what was once Mother Nature's river. What the photo shows is what I've often taken Iowa City's visitors to see: the most excitement Johnson County has to offer; our equivalent of the deck of a cargo ship crossing the Atlantic Ocean in the winter. This afternoon it was passing 14,000 cubic feet of water per second. That's what it looks like.

Want to know how much 14,500 cubic feet of water per second is? One cubic foot of water is about 7.48 gallons. You may use about 100 gallons each day around your house. By contrast, 14,500 cubic feet a second would be over 9 billion gallons a day (9,370,944,000 gallons). That doesn't help? OK, imagine a one gallon plastic milk bottle. Imagine stacking enough of them to hold this much water; your stack of milk bottles would reach nearly 15,000 miles into the sky (14,796) -- and would be very unstable, my assistant, Kelley Winebold, reminds me. Still doesn't help? Ever driven across the United States, from one coast to the other? The height of this stack of milk bottles is roughly the equivalent of five cross country drives. Oh, well. Never mind. Just go watch the tail water these days. You'll see.

Some 200 years ago we didn't have the Coralville Reservoir to control flooding. We had trees and sturdy prairie grasses to absorb the water and prevent it from running off into streams and rivers. It was we who cut down those trees and plowed under that prairie, we who paved roads and parking lots, we who built homes and other buildings in our rivers' flood plains -- and we who are now paying the price, in numerous ways.

We know what to do to prevent those losses; just as we know what to do to prevent obesity, wars of choice, banking abuses, under-performing K-12 schools, growing national debt, and the ever-accelerating rates of incarceration of Americans.

What we are lacking in each of these cases is the will, the courage, to substitute long-term benefits for ourselves and future generations for the short-term benefits of greed, convenience and complacency. As Connie Mutel says, for this "We are paying the price." And what a heavy price it is.

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kurt said...

I we (the owners) had to pay a significant part of the cost to rebuild, we would not rebuild in the flood plain. Government (taxpayers) should not pay any part of rebuilding in a flood plain.

James Jenkins said...

This is an absurd suggestion. I suppose we could remove flooding if we'd go back and live as the Indians; a stone age, hunter/gatherer way of life. I doubt that the authors would voluntarily return to that sort of existence themselves. This is the sort of exercise we hear of proposed by those on the Coasts suggesting that Iowa, Nebraska, and the Dakotas be returned to the conditions of the 19th Century -- with buffalo roaming and all the rest. Ridiculous, especially if you like to eat.

Nick said...

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Unknown said...

While it is true we have too much concrete and drainage tile, there is also the concern that the flooding of 2014 could have been prevented by better management practice by the USACE.

Nick said...

Tim Weitzel: There are instances in which I read of an institutional decision (government, military, corporate, university, school board) and think I have a better way than what it decided to do. I'm not sufficiently delusional to believe that when I have those thoughts I am always right, and the institutions' administrators are clearly wrong. But those are my thoughts.

But in this case, I'm not confident I could do better than the Army Corps of Engineers. I'm not saying there's no chance I could do better; I don't know enough to say that either. It's just not obvious to me what their error is, and how precisely one can reasonably expect them to make these judgment calls. It's kind of a classic multiple-variable analysis problem -- and one for which experimentation cannot really be designed. Is it going to rain? When? How much? Where? With what likelihood of runoff? How much needs to be held in the Reservoir for future individual and institutional use downstream during the months to come?

I certainly wish it could be a really precise science/algorithm. I'm not sure it can be.