Overflowing Rivers and Streams Are the Third Costliest Natural Event for US Homeowners

While coastal flooding from hurricanes tends to get the most media attention, riverine flooding affects all fifty states and is on the rise due to climate change. Riverine flooding, which can occur when streams or rivers overflow their banks, presents a significant threat of property damage that homeowners should be aware of. To explore the impact of riverine flooding on homeowners, MoneyGeek analyzed data from the Federal Emergency Management Agency’s (FEMA) most recent National Risk Index to determine the expected cost of property damage per year due to riverine flooding events.

• Damage to property caused by riverine flooding is expected to cost $2.9 billion every year. Riverine flooding is the third costliest natural cause of property damage, behind hurricanes and earthquakes.

• The cost of property damage from riverine flooding is highest for residents of Louisiana, where annual expected losses total $51 per person.

• Texas can expect to lose $962 million in property damage to riverine flooding annually, the highest total loss in the nation; the state also has the second-highest expected per capita cost ($32) in the U.S.

• Connecticut experiences the least flooding in terms of costly damage to property, with just $0.63 per capita in expected yearly damages.

• Riverine flooding affects all states and is four times costlier than coastal flooding.

So which states are most at risk of experiencing economic losses from riverine flooding? Some states and regions are more flood-prone than others, with five of the top ten states for losses in the Southeastern United States.

The number one state for flood losses, Louisiana, has an expected property damage per capita of $51 per person. That’s much more than the second state on the list, Texas, where residents were expected to pay $32 each in damages. However, because Texas is more populous, its total projected flood losses came in at a staggering $962 million, while smaller Louisiana’s losses are projected to be $232 million.

Although flood losses are more likely in the Southeast, flooding can happen in all fifty states. North Dakota, Vermont, Iowa, Nevada and New Jersey also held spots in the top ten states for costliest flood losses.

MoneyGeek found that riverine flooding is four times more costly than coastal flooding. Given that riverine flooding affects all fifty states and coastal flooding only touches thirty-two, this may not be surprising, but the monetary difference between the two types of predicted flood damages is staggering: $2.9 billion is expected to be lost to riverine flooding, compared to $783 million to coastal flooding.

Flooding risks are increasing due to climate change, and flood damage is predicted to rise 26% over the next thirty years. As the atmospheric temperature rises, so does the amount of moisture in the air, increasing the chances of rain and sudden violent storms that can cause flash flooding.

While riverine flooding can happen in any area where available natural or constructed channels for water are full, flash flooding can cause large amounts of water to move rapidly through an area. Due to the water’s density, these flooding events can be extremely dangerous. FEMA estimates that water from a flood moving at 10 miles per hour can put as much pressure on a structure as 270 mile-per-hour wind gusts.

Although every state in the country is potentially at risk from riverine flooding, some communities bear a higher risk than others. Over the next thirty years, flooding in poor communities, particularly those with large Black populations in the American South, is predicted to increase by 20%. Often, the municipalities in these areas have yet to invest in flood adaptation or improved infrastructure, and studies show that during disaster recovery, poor communities are less likely to receive aid than wealthy communities.

MoneyGeek’s comprehensive guide to hazard, flood, and earthquake insurance can help if you still have questions about whether you need flood insurance, as well as what is and is not covered.

MoneyGeek analyzed FEMA’s 2021 National Risk Index data — the most recent data available — to determine expected annualized property damage losses from riverine flooding events across the country. Our analysis included property losses from damage caused to buildings due to the overflow of streams, rivers and constructed channels. We analyzed total property damage and ranked states by per capita losses to determine which states are the most burdened by property damage due to riverine flooding.

If you have any questions about MoneyGeek’s findings or methodology, please reach out to Melody Kasulis via email at melody@moneygeek.com.

The data points presented are defined as follows:

• Rank: Determined by the state’s Expected Property Damage Costs per Capita, with a lower rank indicating a higher expected per capita losses.
• Expected Property Damage Costs per Capita: Yearly total expected losses to buildings due to riverine flooding per the number of residents.
• Total Expected Property Damage Costs: Yearly total expected losses to buildings due to riverine flooding.