By Kit Wiberg
Loaded up with camera gear and permission from the U.S. Army Corps of Engineers to get up close, John Moon III made his way to Harry S. Truman Reservoir in Warsaw.
A contracted stormtracker for KSN-TV in Joplin, Moon stood on the side of gushing floodwaters during the flooding in 2019.
The water being 30-40 feet above a normal pool, Moon struggled to shield his equipment from the spray of the water.
“The spray itself [from the floodgates] made me feel like I was in a rainstorm,” Moon said.
Every Missourian remembers the powerful rain and flooding in 2019 — events that caused widespread destruction and financial loss across the state.
Farmers lost their livelihood for months and families had to offload heaps of cash for flood insurance after losing their homes. Residents in Missouri received more than $93 million in federal reparations for damages.
The reality of flooding is tragic. It strikes hard and fast, leaving devastation in its wake. Missouri can expect more of this flooding as unpredictable climate change patterns continue to create threats to the environment and the species that depend on it.
While it can be challenging to adequately prepare for flooding, there are ways to mitigate the effects of climate change. This may help lower the frequency and risk of severe flooding events.
The connection between climate change and flooding is disastrous. Further exacerbated by human activity, climatic instability may become more frequent leaving people wondering if the thunderstorm that is supposed to happen the next day will lead to the loss of houses and farmland.
The more intense the changes in the climate, the more intense the repercussions will be.
Developments in Climate Change
The effects of climate change have intensified across the state, and scientists have identified a connection between the earth’s heating and an increase in flooding events.
The rise of greenhouse gasses, like carbon dioxide, in the air has warmed the surface of the earth by one degree in the last 50 years, according to a report by the United States Environmental Protection Agency (EPA).
This amount of carbon dioxide is higher than ever before and is directly related to human activity. While that one degree might not seem consequential, it is enough to affect the heating and cooling of the atmosphere, thus leading to shifts in the temperature of the earth.
In Missouri alone, the average annual temperature has been increasing since the late 1990s. Patrick Guinan, a Missouri state climatologist, found that the average temperature in 2012 was 58.5 degrees.
This is four degrees hotter than the average temperature Missouri experienced over the last 125 years. The temperature in 2012 is the highest recorded temperature Guinan has seen since he began tracing the state’s temperature patterns from records starting in 1895.
The overall rise in average temperature has led to a quicker evaporation rate across the state, which increases humidity levels, heightens average rainfall and causes more occurences of intense thunderstorms.
Higher levels of rainwater lead to more street runoff that usually flows into the nearest body of water. If there is enough runoff to fill up nearby bodies of water, rainfall will start overflowing into the streets and surrounding areas.
“I believe unless we take preventative action, we are going to be spiraling in terms of our climate,” Moon said, explaining that preparedness begins at the local level and everyone needs to do their part to help authorities respond to big things like climate change and flooding.
The Relationship Between Precipitation and Flooding
In his research, Guinan has found that there’s been a jump in heavy daily precipitation events, like rainfall, across the state by studying rainfall events that were at least three inches.
The study by the EPA also reported that the average annual precipitation in the Midwest has increased by 5-10 percent over the last 50 years. The report said that during Missouri’s worst flood in 2011, the amount of water in streams was 20 percent greater compared to previous years.
By looking at an accumulation of data from 28 weather stations statewide, Guinan noticed that between 1895 and 2019, there was a total of 17 days on average each year where rain exceeded three inches.
During the years 2000 to 2019, however, those daily rainfall events increased to 23 per year. If this trend continues, flooding will only increase and will have vastly more powerful effects on the number of devastating floods that occur in the Midwest each year.
But this might not seem like a big deal to some Missourians, as anyone who has lived in the state long enough has experienced flooding to some degree.
People remember things like the whoosh of torrents of water as it rushes through the streets or the squelch of a shoe that’s sunk into a muddy field as a person walks through a flooded field.
Flooding has become normalized enough that most people in Missouri think nothing of it.
Back in 2019, as Moon was capturing the dangerous unrest of the Truman Reservoir, he watched as all four of the reservoir floodgates were forced open and started overflowing by the onslaught of water.
“At the time, it was unheard of to have the floodgates open for such long periods of time,” Moon said. “The whole system was waterlogged.”
The prolonged flooding events of 2019 impacted many more people locally than most realized. According to Moon, citizens from several towns, including Warsaw, were asking why authorities were not releasing water.
The water was building up, getting closer and closer to cascading over the top of the barriers, but the Army Corps of Engineers had to wait for the water level downstream to lower before they unleashed the built-up water into the already-flooded system.
“That’s one thing I noticed… the water levels were really increasing,” Moon said. “There was just so much rain and there was no place for the water to go.”
On April 7 of this year, Columbia (Mo.) faced a flood that left water leaking into buildings and parks. At 6 that morning, the water in Hinkson Creek was at 4.12 feet — around average.
When 8:30 p.m. rolled around, the water had reached an action level of 13.61 feet. Eastgate Plaza had so many inches of rain that water exploded out of a sewer in the parking lot, causing even more runoff and cracked pavements.
Some Columbia businesses were also casualties of the intense flooding. Clovers Natural Market had to close down until May 1 to repair a storm drain that had overflowed with rainwater.
The Missouri River is plagued by several other problems in addition to dangerous flooding. American Rivers listed the lower Missouri River among America’s Most Endangered Rivers of 2020, reporting that this river is one of the most controlled and engineered rivers in the nation.
The many artificial channels, dams and levees work to try to control floods. But all of those manmade interferences with the river create a narrower path for the water that does not give it much room when rising.
Missouri River Flooding Hazards: Levees
Since flooding will get worse along with climate change, failing levees are only adding to the intensity of floods.
Levees are man-made embankments designed to keep water within the bounds of the river. Although they can be helpful, failed levees can cause immense damage.
When levees develop holes or fail completely from intense or constant flooding, the water held back crashes through and flows wild.
Imagine filling a bathtub to the brim but not turning off the water. Instead, the water continues cascading over the side, engulfing everything within minutes. That is what it’s like when a levee is breached or crashes.
According to Russell Errett, a hydraulic engineer for the Corps, these structures become weakened when flood levels increase.
Excessive use of alcohol and drugs also affects “They can only take so much wear and tear and having water on them for so long,” Errett said. “There’s a lot of maintenance that goes into them.”
According to American Rivers, 850 miles of levees were damaged during the flood in March of 2019. The Corps states that repair costs will exceed $1 billion.
Certain areas in the river have very narrow embankment walls, according to American Rivers. When the water starts to rise, embankments are not tall enough to hold it all back and the water has nowhere else to go but out.
This is where the main problem occurs. Once the water breaches those embankments, known as a levee failure, the water spills into land surrounding the river called a floodplain.
When the water fills the floodplain to its capacity, it erupts from this temporary basin and takes down anything in its path.
Levee setbacks are one solution to the excessive flooding affecting levees. Instead of having the levees run with the contour of the river, they would be placed further back, giving the water more room without causing any added destruction, according to Errett.
Jim Karpowicz, a videographer for the Missouri Coalition for the Environment, thinks it would be ideal to have levee setbacks in many more places along the Missouri River.
During the 2019 flood, failed levees drowned crops, ruined land from the sopping soil and tore down structures. But then some residents advocated for levee setbacks to prevent the disastrous effects floods were inflicting on native farmland, to which the Corps agreed.
]“This is very successful and kind of innovative that local landowners proposed this, and that’s why it has gotten so much support,” Karpowicz said. “…the local farmers are like ‘this is what we need to do.’ So that’s what’s happening.”
“Levees are very static,” said Eileen Shader, director of river restoration for American Rivers National Floodplain Restoration Program. “They are only designed to a certain point… there’s a 1 percen t chance every year that the flooding can occur. But with climate change, it is affecting the frequency and severity of flooding events.”
Extreme Precipitation Leads to Runoff
Most Missourians are familiar with the experience of walking down the street after an intense rainstorm. The streets are usually still covered in rushing water as it makes its way to storm drains and the local waterways.
This runoff can cause more harm than simply just the hassle of getting your socks wet as you walk outside.
The fourth National Climate Assessment states that “runoff from extreme precipitation events can exceed the capacity of stormwater systems, resulting in property damage, including basement backups.”
Additionally, in some urban areas there are sewer systems in place that use treated sewage and stormwater together.
Extreme rain can interrupt these systems by overflowing and cause raw sewage to runoff into local rivers and streams, creating not only environmental problems but also health risks for the community.
Not only can runoff ruin properties and burst storm drains from the volume of water, but it can also contaminate the water with sewage. When this happens, the polluted runoff mixes with the water from rivers that will become drinking water.
“Where there’s more frequent flooding, there are probably older mixed systems,” Errett said. “So, it’s just when there are large heavy rainfall events, the sewage plant overflows. And so that puts raw sewage into the river.”
With rising temperatures and precipitation events, this overflow is projected to occur more often. Errett explains that this is not as bad as one would think as the contamination can become diluted and even treated.
But as climate change continues along the trend of increasing flood rates, this problem could become worse and send more untreated sewage into local water supplies.
End All, Be All?