As Hurricane Laura Bears Down on Gulf Coast, Data Shows How COVID-19 May Affect Evacuations

August 26, 2020 | 6:30 am
Kristy Dahl
Principal Climate Scientist

With Hurricane Laura churning toward the Gulf Coast, hundreds of thousands of people on the Texas and Louisiana coasts are currently under either voluntary or mandatory evacuation orders. Along with the thousands of people who have evacuated their homes due to wildfire threats in California, Gulf Coast evacuees will be adding to the ranks of those hoping to find safer shelter from climate-related events in the time of COVID-19.

It is critical that people in evacuation zones heed local evacuation orders, as the risk of staying put may be grave. But fears of contracting COVID-19 are clearly also top of mind, and personal finances are already strained for many, which may lead potential hurricane evacuees to weigh their options differently this year. What can the data from previous hurricane evacuations tell us about how evacuation may play out this year?

Evacuation decisions are complex and multifaceted

Evacuating one’s home involves countless decisions big and small including whether to evacuate or stay put, where to go, what type of accommodations to stay in and what the costs would be, how to get there, how to prepare your home, when to leave, and when to return. The fact that the status quo is that these decisions fall to individuals or families speaks to the ways in which our society underprepares for disasters. That said, a few years ago, a team of researchers at the National Center for Atmospheric Research developed a model that’s useful for thinking through the many factors that play into a household’s evacuation-related decisions:

Evacuation decision model adapted from Lazo et al. 2015. Red boxes show components of the decision making process that could be different this hurricane season because of COVID-19 and the associated economic fallout.

Conditions particular to a given hurricane—e.g. if it is expected to be a Category 1 or a Category 5 at landfall—clearly influence how potential evacuees appraise the situation, as do the messages, warnings, and orders issued by trusted officials.

In addition to that external information, individual and household characteristics as well as situational motivations or barriers influence how potential evacuees assess their options. Many sociodemographic factors have been shown to affect decision making around evacuation and personal circumstances may limit the choices potential evacuees feel they can make. Some studies show that being elderly, having children, having more education, and being more socially connected influence people toward evacuating. Other factors, such as not being employed full time, influence people toward staying in place. Race and home ownership show mixed results in terms of how they affect evacuation decisions.

Of these, employment status—and therefore household cash flow—is quite different this year than it has been in past years. Unemployment data from the Bureau of Labor Statistics show that, like most of the country, Gulf Coast communities have experienced an increase in the percent of their population that is unemployed.

In Jefferson Parish, Louisiana, for example, the number of people unemployed has increased from about 7,700 in June of last year to nearly 26,000 in June of this year, roughly a tripling in the parish’s unemployment rate. In Galveston County, Texas, nearly 16,000 people are currently unemployed compared with about 6,500 a year ago.

Studies have found that between transportation, food, and lodging costs, the total cost of evacuating can add up to hundreds of dollars or more. People in coastal areas may be looking at evacuation differently this year because their pocketbooks are already strained following the pandemic-fueled economic downturn.

Change in unemployment rate over the last year. Pinks and reds indicate places where the unemployment rate has increased. Click here to explore the data.

While potential benefits, such as keeping family members safe or being able to work remotely weigh in as pros for evacuation, potential barriers, such as having underlying medical conditions that could put a person at higher risk for a severe COVID-19 infection, could deter people from evacuating who would otherwise.

Importantly, research has also shown that peoples’ risk perceptions and sense of self-efficacy—basically the belief in one’s capability to achieve a certain result—also play into evacuation decisions. With a majority of surveyed people in the US seeing COVID-19 as a big problem, we’d expect the perceived risk of COVID-19 exposure to factor into evacuation decisions. And with susceptibility to the disease controlled, in part, by the behaviors of those around us, potential evacuees may question the strength of their self-efficacy for maintaining health and safety while evacuating.

Accommodation types and funding for different accommodation options

With the intersection of COVID-19 and hurricanes or other natural disasters in mind, FEMA, the CDC, and the Red Cross have all indicated that hotels, dormitories, and other small shelter options that allow evacuees to avoid shared spaces and facilities would be prioritized this year over large shelters with shared facilities. When it comes to implementing such a policy, though, emergency managers in Florida have encountered so many problems that they’ve shelved it in favor of a more typical approach to sheltering. Particularly for those with underlying medical conditions or concerns about the cost of sheltering, the prospect of having to live in close proximity to dozens or more of their neighbors could make them reluctant to evacuate even when the risks of staying home during a hurricane are so high.

There is particular concern in Black communities that the risks posed by this hurricane season will compound existing inequities in financial and physical well-being. My colleague Juan Declet-Barreto writes about the inequity of seeking safety here. And while community groups are preparing to provide shelter, food, outdoor showers, and other services to evacuees, the fact remains that the extent (or lack) of preparedness in any given county for the dual threats of COVID-19 and hurricanes is not always clear to the general public.

Minimizing risks of COVID-19 transmission during an evacuation

As people evacuate from storm-affected regions to safer areas, they will encounter a range of COVID-19 conditions. Some destinations may present safer conditions—low community infection rates and low rates (i.e. reproductive numbers) of disease transmission—whereas others may be experiencing higher infection and transmission rates. From a disease control and public health vantage, places with low reproductive numbers and infection rates are more attractive, provided these areas can maintain disease control in the face of an influx of evacuees.


Maps of estimated community infection rate (top, in cases per 100,000 people) and reproductive number (bottom, with blues indicating lower rates of spreading and red indicating higher rates) as of August 23, 2020, for counties in the southeastern US. Data and maps courtesy of Sen Pei of Columbia University.

Recently, we found just this effect when simulating a hypothetical hurricane evacuation from southeast Florida (see the study, which is awaiting peer review, here). Model simulations indicated that evacuation is likely to increase the total number of COVID-19 cases; however, directing evacuees to locations experiencing lower COVID-19 transmission rates while simultaneously minimizing human contact during evacuation could reduce the excess number of infections.

Currently, estimated infection rates and reproductive numbers in the Gulf region vary greatly from place to place. Emergency managers and individuals could incorporate this information into their decision framework when directing evacuees out of the landfall region or deciding where to go. Such direction could help minimize transmission of the virus in both evacuee and host communities, and similar consideration can be applied to other emergency evacuation settings, such as the California wildfires.

It’s vital that people heed mandatory evacuation orders even in the midst of the COVID-19 pandemic while following public health precautions as much as possible. No one should face discrimination because of the COVID-19 infection rates in counties they are forced to flee to stay safe from the effects of hurricanes.

I started writing this post at the end of last week–a long week for Californians. All week I stared wearily at a blank page, trying to will myself to write about decision making amongst hurricane evacuees and would-be evacuees. Meanwhile my heart felt clenched as I watched ash from the 500+ wildfires in the state dust my porch and wiped it away from the dining room table after we mistakenly left a window open one night. Nearly 120,000 people had evacuated from the homes and communities threatened by wildfires. That’s 120,000 people—roughly the population of Stamford, Connecticut–seeking safety and shelter amidst a pandemic, some finding shelters too crowded and deciding to simply sleep in their cars.

In the coming days, those evacuating from Gulf Coast communities will face many of the same difficult choices of where to go and how to shelter safely during the pandemic as those who have fled their homes due to wildfires this past week. Hesitating to evacuate when doing so could mean risking exposure to COVID-19 or draining the last bit of one’s savings is understandable. Our sincere hope, though, is that those who are ordered to evacuate comply those orders and are able to do so safely and affordably. State, federal and local authorities must do their utmost to help people—particularly those who are most vulnerable–stay safe, including providing shelter, food, transportation and other resources that communities might need during emergency situations. Our hearts are with you.

Columbia University researchers, Jeffrey Shaman and Sen Pei, contributed writing and analysis to this post.