Overflowing Buckets and Inundated Sandbars
Originally published in The Living Land column in The Hawk Eye on July 28, 2017
Today is the 77th day this year that the Mississippi River stage at Burlington exceeded the 15 foot flood stage. The river level here at Burlington has exceeded flood stage for just over one out of every three days this year.
Big deal, right?
Actually, it is kind of a big deal. Especially if you’re one of the thousands of people that enjoy spending time on the water. Or if you’re concerned about the ecology of the river’s various habitats.
If by chance you’ve followed my column since 2013, this will sound familiar. The river spent a total of 91 days above flood stage in 2013, the second most since record keeping began in 1917. Only the year of the Great Flood, 1993, had us flooded out longer at a whopping 151 days.
Now here we are again four years later. Just over halfway through the year and we’re already in fifth place for the most days spent above flood stage. Six more days above flood stage and we’ll earn bronze. Fourteen more days and we’ll tie with 2013 for the second most number of days spent above flood stage in any year ever.
So what’s going on?
Naturally, we want to point the finger at one single villain. We want that one silver bullet that will solve all our problems so we can just get back to boating on the sandbar the way we did in the good ole days. Just dredge the river deeper. Make Keokuk open the gates on the hydroelectric dam. Build a taller floodwall.
Unfortunately it’s not that simple.
Think of the river system like a series of buckets on a set of stairs. Each bucket has a hole in its side that lets water out into the bucket below it. Each bucket also has a number of hoses pouring water into it. Each hose represents inputs of water, such as from direct runoff or from the tributaries that feed it. Each hose’s “valve” reflects not just the amount of rain that falls in that particular watershed, but how fast that water runs off into that tributary.
The water through all those hoses runs into those buckets and those buckets can release that water into the next bucket only so fast, no matter how big you cut the discharge hole. Pour water into the bucket faster than the bucket can drain it and the bucket overflows.
Now one might say the solution is to just get a taller bucket to hold more water. Dredge the river deeper or build taller levees and floodwalls. Open the gates so the bucket discharges more.
Then it rains eight inches in 72 hours like it did last week in the upper part of the river’s watershed. More water through the hoses.
Then we add more concrete streets and parking lots and more rooftops and more impervious surfaces and drain pipes throughout the community. We run the water down to the river faster. How many more rooftops and concrete surfaces exist just in our little community than we had in, say, 1993? Now take that times every growing community in the Mississippi River watershed above us.
More water through the hoses.
Then plow up more area and convert wetlands and forests and floodplains and prairies into crop fields and pastures. Then when it’s still too wet, add miles and miles of drainage tile and ditches to get the water off the fields and into the river faster. Then throw in a changing climate where several-inch localized rains become more intense and frequent.
What did we think would happen?
Now we could just continue to do what we’ve been doing for the last few decades and keep FEMA on speed dial and watch our riverine ecosystems get washed downstream. Or we could face the fact that we’re only going to make our high water issues worse if we keep reducing the land’s ability to hold the water that gets dumped on it. Our buckets are just going to keep overflowing no matter how tall they are if we keep increasing the rate at which they’re filled.
We have to start asking ourselves whether another foot of drain pipe is worth another week underwater or another foot of flood crest.
Tired of being flooded out all the time? Stop telling Facebook and start telling your elected officials, your community planners, your neighbors. Start demanding wetlands, buffer strips, riparian corridors, bioswales, greenspace, floodways, reclaimed floodplains, low impact development, and investment in water quality and management practices.
Until we start taking our water problems seriously on the landscape behind us, we’re not going to make a bit of difference to the river levels in front of us.
Today is the 77th day this year that the Mississippi River stage at Burlington exceeded the 15 foot flood stage. The river level here at Burlington has exceeded flood stage for just over one out of every three days this year.
Big deal, right?
Actually, it is kind of a big deal. Especially if you’re one of the thousands of people that enjoy spending time on the water. Or if you’re concerned about the ecology of the river’s various habitats.
If by chance you’ve followed my column since 2013, this will sound familiar. The river spent a total of 91 days above flood stage in 2013, the second most since record keeping began in 1917. Only the year of the Great Flood, 1993, had us flooded out longer at a whopping 151 days.
Now here we are again four years later. Just over halfway through the year and we’re already in fifth place for the most days spent above flood stage. Six more days above flood stage and we’ll earn bronze. Fourteen more days and we’ll tie with 2013 for the second most number of days spent above flood stage in any year ever.
So what’s going on?
Naturally, we want to point the finger at one single villain. We want that one silver bullet that will solve all our problems so we can just get back to boating on the sandbar the way we did in the good ole days. Just dredge the river deeper. Make Keokuk open the gates on the hydroelectric dam. Build a taller floodwall.
Unfortunately it’s not that simple.
Think of the river system like a series of buckets on a set of stairs. Each bucket has a hole in its side that lets water out into the bucket below it. Each bucket also has a number of hoses pouring water into it. Each hose represents inputs of water, such as from direct runoff or from the tributaries that feed it. Each hose’s “valve” reflects not just the amount of rain that falls in that particular watershed, but how fast that water runs off into that tributary.
The water through all those hoses runs into those buckets and those buckets can release that water into the next bucket only so fast, no matter how big you cut the discharge hole. Pour water into the bucket faster than the bucket can drain it and the bucket overflows.
Now one might say the solution is to just get a taller bucket to hold more water. Dredge the river deeper or build taller levees and floodwalls. Open the gates so the bucket discharges more.
Then it rains eight inches in 72 hours like it did last week in the upper part of the river’s watershed. More water through the hoses.
Then we add more concrete streets and parking lots and more rooftops and more impervious surfaces and drain pipes throughout the community. We run the water down to the river faster. How many more rooftops and concrete surfaces exist just in our little community than we had in, say, 1993? Now take that times every growing community in the Mississippi River watershed above us.
More water through the hoses.
Then plow up more area and convert wetlands and forests and floodplains and prairies into crop fields and pastures. Then when it’s still too wet, add miles and miles of drainage tile and ditches to get the water off the fields and into the river faster. Then throw in a changing climate where several-inch localized rains become more intense and frequent.
What did we think would happen?
Now we could just continue to do what we’ve been doing for the last few decades and keep FEMA on speed dial and watch our riverine ecosystems get washed downstream. Or we could face the fact that we’re only going to make our high water issues worse if we keep reducing the land’s ability to hold the water that gets dumped on it. Our buckets are just going to keep overflowing no matter how tall they are if we keep increasing the rate at which they’re filled.
We have to start asking ourselves whether another foot of drain pipe is worth another week underwater or another foot of flood crest.
Tired of being flooded out all the time? Stop telling Facebook and start telling your elected officials, your community planners, your neighbors. Start demanding wetlands, buffer strips, riparian corridors, bioswales, greenspace, floodways, reclaimed floodplains, low impact development, and investment in water quality and management practices.
Until we start taking our water problems seriously on the landscape behind us, we’re not going to make a bit of difference to the river levels in front of us.
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