Six ways the floods of 2015 and 1982 were surprisingly similar
Many St. Louis-area residents were still enjoying a long weekend and the end of the Christmas holiday when the flood warnings first went out on Dec. 26.
Over the next days, the Mississippi, Missouri and Meramec rivers rose to dangerous heights at unprecedented speed in some areas. The water spilled over levees, put water treatment plants out of service, and swamped thousands of homes and businesses in riverside communities.
Then, almost a week later, the icy floodwaters were practically gone.
Along the Meramec River just south of St. Louis, the flood surpassed heights not seen since December of 1982. In fact,that devastating flood 33 years ago — which killed six people in the St. Louis area and wiped out the town of Times Beach — poses some striking similarities to the one experienced just before New Year’s.
They were caused by a lot of rain in a concentrated area, not snowmelt
Severe winter floods are a rare occurrence in the Midwest. Spring and summer floods, like the Great Flood of 1993 on the Mississippi River, are often partially caused by excessive snowmelt from the prior winter.
The fact that sheer rainfall, concentrated in a few areas, created record-breaking floods in 1982 shows just how much water there was.
As in 2015, the unseasonably warm temperatures in November and December 1982 were also punctuated by above-average rainfall. Storms between Dec. 2 and 7 caused the first series of floods, which affected Missouri, Illinois and Arkansas.
At the National Weather Service offices in St. Louis, senior hydrologist Mark Fuchs found an old inter-agency report that had been prepared to discuss the flood of 1982 and its aftermath.
“I remember looking at this stuff and thinking, ‘Wow. Wow, wow, wow,’” Fuchs said.
This latest flood surprised him; he said he hadn’t expected to see a winter flood of that scale before he became an old man.
“In many respects, it was very similar,” Fuchs said, as he reviewed the rainfall data. “Five to eight inches is a pretty good guesstimate of how much they had to trigger that record flooding, not terribly unlike what we had a few days after Christmas.”
Though opinions differ on the effect regional development had on the flooded Meramec last year, Fuchs said Mother Nature had more to say in how high the river grew.
“In my mind, we had more rain without question across the Meramec Basin in this event. It was just a bigger, overall event,” Fuchs said.
The highest flood levels were measured on the lower end of the Meramec
The early December flood of 1982 broke records on the Meramec River. In Pacific, the water reached almost 18 feet above flood stage on Dec. 6. Gauges in Eureka recorded a level about 25 feet above flood stage—even higher than the flood of 1915, the worst on record.
On Dec. 30, 2015, the rising Meramec broke Pacific’s record by 8.5 inches and hit 28 feet above flood stage in Eureka.
“The upper end of the Meramec—Steelville and Sullivan—this time around did not have record flooding. It was a big flood, no question, but just a good, major-to-moderate flood,” Fuchs said. “That was exactly what happened in 1982 as well.”
In the aftermath of the 2015 flood, hydrologists offered multiple perspectives as to why the Meramec broke the record so quickly: the region’s continuous conversion of agricultural floodplain to runoff-prone subdivisions, climate change, and even simply a bad luck of the draw. Hydrogeology professor Bob Criss of Washington University in St. Louis hypothesized that the Valley Park levee itself pushed water at least a foot higher in Eureka and Arnold, and possibly further.
“The magnitude of the effect is clearly correlated with sites that have been most intensely developed,” Criss said. “We should quit rebuilding in these areas and start moving people out, because this phenomenon is going to continue to happen.”
He’s now crunching the data to test his theory. The Army Corps of Engineers disputed Criss’ claim, saying the $50 million earthen levee around Valley Park was designed to inflate water levels by no more than four inches and for only seven miles upstream.
“Everything worked as designed. [The engineers] were extremely happy with how it performed, and it was a great success for us,” said Amanda Kruse, a spokesperson for the Corps.
They happened during an El Niño
An El Niño is a tropical climate event that causes warmer weather in the Pacific Ocean. The effect sometimes reverberates across the climate of North America, causing warmer-than-average temperatures and wetter conditions in the Gulf Coast and Florida, but drier-than-average weather in the Ohio Valley and Pacific Northwest. (El Niño also has a “sister” that causes colder weather patterns, named La Niña.)
What does that mean for the Midwest? Scientists aren’t sure yet. Because there have been only five “strong” or “very strong” El Niño’s on record, there isn’t a whole lot of data, said Fuchs, the hydrologist.
“Sometimes in a strong El Niño, we will have a wet December followed by a drier January and February. There’s other strong El Niño years on record where nothing happened extraordinarily at all, one way or the other,” Fuchs said. “But sometimes other climatic factors come into play.”
According to the Climate Prediction Center at the NWS, one of the biggest El Niño events recorded in the past century occurred in the last months of 2015. Similar fluctuations were recorded in 1997 and 1982.
Water runoff near toxic sites raises concern
Nearly every riverside community damaged during the Meramec’s 1982 flood made a full recovery. The working-class town of Times Beach did not.
That’s because the flood exacerbated a looming environmental disaster: the town’s soil was contaminated with dioxin, a byproduct of Agent Orange. Unbeknownst to the people of Times Beach, the pollutant was mixed in oil, sold cheaply to a contractor, that was spread on dirt roads to keep the dust down, said environmental historian Dave Lobbig of the Missouri History Museum.
“It wasn’t proven to be there until right after the flood,” Lobbig said. “Animals were dying, people were developing rashes and stuff like that.”
The EPA ordered tests. The confirmation of dioxin in the soil came just before Christmas of 1982.
“The people of Times Beach found out, ‘Yes, indeed, we have this stuff in our soil,’ just as their homes and their whole environment had been flooded, and all this stuff had been spread around by the flood,” Lobbig said.
The combination of flood damage and contamination was too much for the small town of Times Beach, which was evacuated later that month. Homeowners eventually received the first federal buyouts for environmental contamination, and the town was bulldozed. The area has since been cleaned up and now exists as Route 66 State Park.
2015’s flood brought its own environmental scare. Residents in the Bridgeton area were alarmed when video footage showed rainwater runoff flowing over the West Lake Landfill Superfund site in north St. Louis County. The site is contaminated with radioactive waste from the Manhattan Project and is part of an ongoing cleanup process that has drawn the frustration of many residents. The runoff was collected by the Missouri Department of Natural Resources and sent to labs for testing, the Post-Dispatch reported.
“All the stuff we’re finding now has some type of cover material on it, whether it be vegetation, or soil, asphalt, concrete, etc.,” Army Corps health physicist Jon Rankins told St. Louis Public Radio. “It’s not going to be going anywhere.”
The scope of the damage
According to historian Lobbig, the 1982 flooding along the Meramec killed six people, severely affected 3,000 residences, and totaled more than $100 million in overall damages—the equivalent of $245,944,041 today. Two major storms that December caused floods that killed 25 people in Missouri, Illinois, Arkansas, Louisiana, Mississippi and Tennessee.
The 2015 floods in Missouri and Illinois caused 25 confirmed deaths. Damage assessments are ongoing, but early geospatial estimates for the St. Louis region put the number of damaged structures (residences, businesses and public buildings) at 7,100. This time, the town of Valley Park was spared, due to a 44-foot levee built after the flood of 1982.
“Overall, I think we should be learning how to better live with our rivers, to live in accord with them,” Lobbig said.
People who had the least lost the most
Here’s something that tends to happen with every natural disaster: the people who lose the most, who are least able to bounce back, are often the ones who had the least to begin with.
In December 2015, multiple mobile home parks located on the floodplain were swamped along the Meramec, and also in Granite City and Pontoon Beach, Ill.
The swift-rising water forced raft rescues when those who had not evacuated could not escape—including Jean Scott, who this reporter met at a Red Cross shelter in Pacific.
“I’m not sure what’s going to happen. Our trailer will probably be condemned, and we’ve got nowhere to go,” Scott said.
For those without savings, waiting for damage reimbursements from FEMA will be a struggle. Some have missed work while dealing with the flood’s aftermath or are staying with family and friends while they clean out and rebuild their homes.
In that sense, all floods are alike.
What are your memories of the 1982 floods? Are there any connections we missed? Leave your thoughts and recollections in the comments.
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