Key facts
- Residents in northern Michigan were unable to purchase flood insurance for their homes.
- Many areas affected by recent floods lack comprehensive federal flood plain maps.
- Federal flood maps are based on riverine flooding and may not account for heavy rainfall events.
- A private company's models suggest significantly more properties are at flood risk than FEMA maps indicate.
- Climate change is cited as a factor increasing the likelihood of extreme weather events like heavy rainfall and snow.
Historic and devastating floods have impacted northern Michigan, leaving many residents without flood insurance and unaware of their risk. The flooding, exacerbated by record rainfall following heavy snowfall, has swamped homes, threatened dams, and washed out roads. Residents like Tom and Diane Peterman and John Solum found themselves unprotected, with Solum's home suffering significant damage despite not being in a designated flood zone.
Experts point to vulnerabilities in the federal flood mapping system, which has not mapped all areas and primarily focuses on riverine flooding, failing to account for risks posed by extreme rainfall overwhelming infrastructure. First Street, a climate risk research company, found that its models, which incorporate rainfall data and map the entire country, identify more than twice the number of properties at significant flood risk nationwide compared to FEMA's maps, with four times more properties at risk in Michigan.
FEMA uses rainfall data for insurance rates but it is unclear if it will be incorporated into flood plain mapping. A 2019 Government Accountability Office report raised concerns that FEMA's maps did not reflect the best available climate science. FEMA stated that 95% of the U.S. population lives in mapped areas, describing the maps as 'snapshots in time,' but did not comment on updating methods for less-populated regions or incorporating new climate science.
The extreme weather events are linked to climate change, with a warmer atmosphere holding more moisture and an unusually warm Gulf of Mexico contributing to heavy precipitation in the Midwest. The flooding in many areas exceeded the threshold of a 100-year flood.