Climate Change: Heavier April Showers
$106.5 million. That’s the projected price tag for flooding damage in Missouri per year for the next 30 years. And climate scientists expect an increase in the number of severe rain events as the climate warms due to the release of greenhouse gases.
As the saying goes, April showers bring May flowers. But the same may also be true for flooding events in Missouri. And flooding can bring a heavy price tag, not only in terms of dollars but in terms of families displaced and livelihoods lost. The First Street Foundation calculated the price tag of flood damage in each state in its new report The Cost of Climate: America’s Growing Flood Risk. First Street Foundation says theirs is the first such study to account for climate change in its projections. First Street Foundation reports there are 29,337 homes in Missouri with a substantial flood risk right now. First Street adds that the National Flood Insurance Program may not be able to cover Missouri’s losses.
Factors in flooding
Climate change is not the only factor when thinking about flooding. While warming average temperatures could play a role in increased future flooding, it’s important to remember flooding is a complex issue in Missouri.
Levees along Missouri’s rivers are outdated in many areas and in need of repair. Failing levees can lead to catastrophic flooding in residential areas and cropped fields. The watershed and substrates within the rivers impact their ability to flood.
The MOST Policy Initiative talked to the experts in a recent briefing on flooding. Learn more about the different factors that influence flooding here.
Flood insurance may not be enough
Homes in Special Flood Hazard Areas (SFHA) are required to purchase flood insurance through the National Flood Insurance Program (NFIP) if they have a federally backed mortgage such as an FHA or VA loan. Today there are 8,290 Missouri homes in SFHAs. Owners of homes outside SFHAs are still able to purchase insurance through the NFIP at a reduced rate. The foundation calculates there are 21,047 homes outside of an SFHA, but still at flood risk due to climate change.
For the entire U.S., First Street calculated the average annual loss for properties at any risk of flooding over the next 30 years. The Foundation expects an annual average loss of $3,343 per property, per year in these areas. The average annual flood insurance premium for a home in the National Flood Insurance Program (NFIP) is $902 per property in the U.S. That means the annual average loss for the NFIP is 3.7 times higher than its premiums nationwide.
In Missouri, flood losses are expected to be 3.9 times higher than flood insurance premiums over the next 30 years. The Foundation estimates a payout of $4,272 per property at risk of flooding in Missouri in the NFIP. The average annual flood insurance premium for homes in SFHAs is $1,094. Over 30 years, the deficit for the NFIP is projected to be $2.64 billion in Missouri alone.
Climate change may lead to heavier rains
Climate Central reports 220,000 Missourians are living in areas the Federal Emergency Management Agency has designated as a 100-year floodplain. A 100-year flood plain is defined as an area that has a one percent chance of flooding every year. Statistically, widespread flooding in 100-year floodplains is only expected to happen once every hundred years. However, many areas around the country are experiencing once-in-a-hundred-years flood events more frequently.
“We do know that with a warmer climate… more water in the air is definitely possible simply because the warmer air is, the more water it holds. When you have something (to wring the water out) like a cold front, the more water falls out. Thus we’ve seen increased heavy rainfall events.”
Doug Kluck — Director for the Central Region at the National Oceanic and Atmospheric Administration
Climate scientists in Missouri say flooding risk in the state is increasing due to an increase in water vapor in the air as the earth warms. Doug Kluck, Regional Climate Service Director for the Central Region at the National Oceanic and Atmospheric Administration (NOAA) updated the Missouri Local Science Engagement Network (MO LSEN) in a recent roundtable discussion. Kluck explains, “We do know that with a warmer climate… more water in the air is definitely possible simply because the warmer air is, the more water it holds. When you have something (to wring the water out) like a cold front, the more water falls out. Thus we’ve seen increased heavy rainfall events.”
“When I look at Missouri, temperature, and precipitation wise, we’re getting warmer and we’re getting wetter… The data doesn’t lie. We have really a really nice, solid record of temperature and precipitation going back over 100 years. And when you look at the numbers, plot them and chart them, you see that upward increase. Four out of our top five wettest years on record have occurred since the 1970s. This all translates to more flooding. Our warming has been going on in Missouri since the late 1990s. We’ve only had five years since 1998 that were cooler than normal.”
Dr. Pat Guinan — University of Missouri Extension
Dr. Pat Guinan, PhD. of the University of Missouri Extension also joined the recent roundtable discussion. He explained Missouri can expect to see the number of significant rainfall events increase in the future. “When I look at Missouri, temperature, and precipitation wise, we’re getting warmer and we’re getting wetter… The data doesn’t lie. We have really a really nice, solid record of temperature and precipitation going back over 100 years. And when you look at the numbers, plot them and chart them, you see that upward increase. Four out of our top five wettest years on record have occurred since the 1970s. This all translates to more flooding.” Guinan continues, “Our warming has been going on in Missouri since the late 1990s. We’ve only had five years since 1998 that were cooler than normal.”
Missouri’s mitigation plans
Missouri’s State Emergency Management Agency (SEMA) reports flooding has resulted in more disaster declarations in Missouri than any other hazard. SEMA reports Missouri sustained 47,700 property losses due to flooding since 1978, resulting in $813 million in total flood insurance payouts.
First Street Foundation’s findings point to a possible sharp increase in the future. In the last 50 years, Missouri averaged $16 million in flood insurance payouts per year, contrasting with the Foundation’s projection of $106.5 million per year over the next 30 years. SEMA’s Hazard Mitigation Plan acknowledges the likely increase in the intensity of future rain events and warns of future flooding in Missouri’s flood plains and rivers. The National Climate Assessment as reported by Missouri’s State Emergency Management Agency (SEMA) shows that Missouri is likely to experience temperatures 4.1° F warmer on average in the next 50 years. SEMA acknowledges future conditions in Missouri may be associated with increased flooding in the state.
SEMA recommends focusing flooding mitigation efforts on the top ten counties at the highest risk for buildings damaged, property damage, and displaced people due to flooding. The ten counties at the highest risk include St. Louis City, Jackson, St. Charles, Jefferson, Pemiscot, Franklin, Boone, Clay, and Cape Girardeau. SEMA’s recommended flood mitigation efforts include flood insurance studies, increased funding for flood insurance awareness, the creation of flood risk maps, and communication to residents about the flood risk in their homes.
