New to Flood Risk Assessment? Here’s What You Should Know


Flooding is the most common natural disaster in the United States. From Arizona’s deserts to Tennessee’s creeks—from Florida’s coasts to Manhattan’s city center—people all over the country have experienced the devastating effects of flood waters firsthand.


Still, destruction does not have to be the end-all of floods. Simple steps can be taken to protect your business, home, or community against the damage caused by this powerful natural force. The first step is a flood risk assessment.


Flood risk assessments are personalized evaluations that help you understand what flood damage scenarios your property or infrastructure is susceptible to, and how likely those scenarios are to happen. We’ve compiled these must-knows of flood risk assessment to help you secure your livelihood and avoid catastrophic damage down the line.


What Causes Exposure to Flood Risk?


Exposure to flood risk is often caused by a combination of natural and manmade factors. Changing weather patterns, city development, local topography, altitude, and geographic location may all play a role in how likely your place of business or residence is to incur flood damage.

Coastal zones tend to be the most vulnerable to flood risk. In these areas, site-specific conditions like storm surge, high tides, and wave action can cause water levels to rise quickly and dramatically. Over time, coastline erosion may occur, increasing the risk of catastrophic structural damage. Coastal regions are also the first to be impacted by flood-baring natural disasters such as hurricanes and tsunamis.


But it isn’t just coastal areas that are at risk of flooding. According to Pew Research, “While flooding in coastal areas draws heavy media coverage, 8 of the 10 states that experienced the most flood-related disaster declarations over the past decade were inland.” Proximity to smaller, landlocked bodies of water such as lakes, rivers, and dams may also contribute to an increased likelihood of flood damage.


Both coastal and freshwater-adjacent areas are considered Special Flood Hazard Areas (SFHAs) by the Federal Emergency Management Agency (FEMA), and have at least a 1 in 4 chance of flooding during a 30-year mortgage. But being in a special hazard area isn’t the only thing that makes a location vulnerable to flooding. As the saying goes, anywhere it can rain, it can flood.


According to FEMA, people in low to moderate hazard areas file more than 20 percent of all National Flood Insurance Program (NFIP) claims and receive one-third of federal disaster assistance for flooding. Heavy rainfall, depleted natural barriers, blocked sewer lines, high groundwater levels, over paved roads, and increased frost depth can all put you at risk for flood damage regardless of how close you are to a body of water.


Who Should Assess Their Flood Risk?


Businesses, community planners, property managers, developers, and homeowners should all look to get a flood risk analysis. To do this, it is important to remember that to the naked eye, flood risk isn’t often clear-cut.


If your property or community has experienced flooding before, you may have an idea of the type of situation that could cause flood damage again. However, every structure, location, and occasion is different. Flood projections change over time. Unseen points of ingress and rising water levels could jeopardize even the most superficially prepared establishment.


“The fact is, very few people live and work in areas which are ‘flood proof,’” says Jeff Reitsma, Vice President and Practice Lead at 30 Forensic Engineering. “It’s always better to make informed decisions regarding your own personal risk, regardless of where you are and what you do.”


Whether your company just relocated its corporate headquarters to a shiny new building, your community received federal assistance to rebuild after a supposedly once-in-a-lifetime flood, or you own a property that has been in your family for 30 years, the same idea holds true: Without a flood risk assessment, your expectations of safety may not align with reality.

water in the streets with bright neon lights

Why Assess Your Flood Risk?


Floods aren’t an anomaly: In fact, they are growing more frequent. A paper by the European Academies’ Science Advisory Council (EASAC) found that global floods and extreme rainfall events have increased by more than 50% this decade and are occurring at a rate four times higher than in 1980.


The National Environmental Education Foundation echos this concern, warning that by 2050, most U.S. coastal areas will likely be threatened by 30 or more days of flooding per year.


“The risk of flooding has never been higher,” Reitsma says. “And that risk is going to continue to increase as climate change brings larger storms and higher sea levels. There are always opportunities to be more prepared and resilient in these uncertain times.”

Not only are floods happening more frequently, but they are also getting more expensive. According to NOAA, floods cost an average of 4.3 billion dollars per event. That includes physical damage to residential, commercial, and municipal buildings, material assets, public infrastructure, business interruption, and restoration efforts. Oxford research asserts that “a mere 1% increase in annual precipitation may lead to a 6.5% increase in annual flood losses,” and that billion-dollar floods are already increasing by about 5% per year.


Whether you are a decision maker for an organization, a community, or a home, here is how unchecked flood risks can affect you and those in your care:


The Stakes for Businesses

Hefty Commercial Claims

Floods can cause thousands of dollars in damage to your business’ products, equipment, and interior. According to FEMA, the average commercial flood claim from 2011 through 2015, was nearly $90,000.


Costly Downtime

For companies that are affected by floodwater, downtime can be extremely costly and hard to quantify. Your company’s revenue stream may take a hit from repercussions that are both tangible (including missed sales opportunities and delayed shipments) and intangible (such as lost productivity and shrinking brand value).


High Customer Churn

While your business works to rebuild after a flood, loss of goodwill amongst your customers, employees, and investors can make a big gash in your bottom line. By the time your business gets back on its feet, you may have already lost your loyal fans to a competitor.


Unwanted Lawsuits

Depending on the nature of your business, flood damage can give your company a lingering stamp of infamy or even land you in court. Power outages, mildew growth, and structural damage caused by flooding can affect your customers’ livelihood, or even put them in harm’s way. Development companies, hospitals, and other organizations have faced lawsuits for not equipping their properties to handle extreme weather events.


Closed doors

Twenty-five percent of small businesses never reopen following a disaster, according to FEMA. Businesses that are hit hard by the repercussions of unpreparedness may be forced to cease operations indefinitely.


Assessing your flood risk and taking active steps to prevent flood damage can not only protect your business, but it can also provide an opportunity for improvement and growth. “If you have a reliable business, it becomes synonymous with how trustworthy your brand is,” says Reitsma. “If you take steps to provide a safe zone in your company, such as by making your lobby flood resistant, including phone chargers, and having a generator that is stored above the base flood elevation, you can have a positive impact on the community when disaster strikes.”



The Stakes for Communities


Displaced Businesses and Residents

Large-scale flood damage can result in the temporary or permanent displacement of local businesses and residents. Damaged schools, transportation systems, and public services may lead to an incalculable disruption of public life.


Damaged Local Economy

Destruction of businesses, homes, and facilities means a huge hit to the local economy. Industries such as tourism, manufacturing, agriculture, and commerce may take months, or even years, to fully recover following a flood. While these industries struggle get back on their feet, some communities may see the local market dry up altogether.


Preventable Death

According to the Red Cross, each year about 150 people die because of floods in the U.S. That’s more deaths than those caused by hurricanes, tornadoes, and extreme temperatures. Many of these fatalities are due to electrocution or other preventable accidents that occur after the floodwaters have gone down.


Lost Investments

The park, stadium, plaza, road, or monument that a local government spent millions of taxpayer dollars building or renovating could be washed away without proper flood risk assessment and mitigation.


Communities who choose to invest in flood risk analysis and flood prevention mechanisms find that their resources are being better spent. A study released by the National Institute of Building Sciences (NIBS) found that for every $1 spent on hazard mitigation, the government saved $6. Rather than pump money into rescuing and rebuilding, communities that are prepared for the next flood can invest in new infrastructure and other initiatives that will ensure the wellbeing of their citizens.

family at the beach

The Stakes for Home and Property Owners


Steep Financial Losses

With the average residential flood claim at $43,000, home and property owners may incur steep losses after a flood. The cost and inconvenience of having to move out during restoration can add to the financial weight of these losses.


Soaring Premiums

Even with flood insurance, properties that have suffered extensive flood damage or that have repeated claims attached to them may get hit by soaring premiums. Depending on the type of flood zone a property is located in, this insurance could cost hundreds, or even thousands of dollars per year. In extreme cases, such as when flooding occurs regularly, insurance may not even be available.


Lost Documents and Sentimental Objects

For homeowners, the consequences of flooding aren’t just financial losses. Many objects of sentimental and personal value cannot be replaced after being damaged in a flood. A flooded residential property means the risk of losing family heirlooms, photographs, documents, and more.


Weakened home foundation

After a flood, a home’s foundation may be weakened. Wet plaster, wallboard, and flooded basements could cause walls and floors to collapse, making these structures dangerous to return to. Injuries, especially back injuries caused by removing bloated furniture, are common after a flood.



Symptoms of stress, tension, and anxiety are common side effects that can last months after a flood is over. Home and property owners that have completed a professional flood risk assessment can avoid this, assuring peace of mind before disaster hits.


Forced upgrades or relocation

After a flood, home and property owners may be required by their local governments to elevate their homes or build sea walls to avoid future risk. These changes can be extremely costly and have even been deemed by some municipalities to be ineffective as sea levels continue to rise. In the chaos of storm recovery, sometimes these mandates arrive late, forcing homeowners to make changes years after a storm has passed.


By undergoing a flood risk assessment and taking the recommended steps to mitigate flood hazards, homeowners can expect their property values to increase, and may even get lower rates on insurance premiums. For many, the simple act of securing their family’s livelihood already makes this a worthwhile investment.



As weather patterns grow more extreme, minor nuisances can become regular hazards. By facing the tough questions sooner rather than later, businesses, communities, and property owners who perform a flood risk analysis will secure their investments, boost their value, and ensure a safe and positive experience for everyone in their care.


For more reading, check out our blog post, How to Assess Your Flood Risk.

By |2019-05-21T11:45:33-04:00May 14th, 2019|Buildings, Construction, News|