What Are the Environmental Impacts of Hurricane Katrina?

Hurricane Katrina leaves legacy of industrial waste, raw sewage and oil spills

Gulf Coast Begins Cleanup In Katrina's Aftermath
Gulf Coast begins cleanup in Katrina's aftermath. Mario Tama/Getty Images

Perhaps the longest-lasting impact of Hurricane Katrina, one of the worst oil spills in history, was its environmental damage that, in real terms, has mainly to do with public health. Significant amounts of industrial waste and raw sewage spilled directly into New Orleans neighborhoods. And oil spills from offshore rigs, coastal refineries, and even corner gas stations have also made their way into residential areas and business districts throughout the region.

Hurricane Katrina: A "Witch's Brew" of Contaminated Floodwater

Analysts estimate that seven million gallons of oil spilled throughout the region. The U.S. Coast Guard says that much of the spilled oil has been cleaned up or “naturally dispersed,” but environmentalists fear that the initial contamination could devastate the region’s biodiversity and ecological health for many years to come, further devastating the region’s already ailing fisheries, contributing to an economic disaster.

Hurricane Katrina: Superfund Sites Flooded

Meanwhile, flooding at five “Superfund” sites (heavily polluted industrial sites slated for federal cleanup), and the wholesale destruction along the already infamous “Cancer Alley” industrial corridor between New Orleans and Baton Rouge, have only served to complicate matters for clean-up officials. The U.S. Environmental Protection Agency (EPA) considers Hurricane Katrina the biggest disaster it has ever had to handle.

Hurricane Katrina: Flooding Contaminates Groundwater

Household hazardous wastes, pesticides, heavy metals and other toxic chemicals also created a witch’s brew of floodwater that quickly seeped down into and contaminated groundwater across hundreds of miles. “The range of toxic chemicals that may have been released is extensive,” says Johns Hopkins University environmental health sciences professor Lynn Goldman.

“We’re talking about metals, persistent chemicals, solvents, materials that have numerous potential health impacts over the long term.”

Hurricane Katrina: Environmental Regulations Not Enforced

According to Hugh Kaufman, an EPA senior policy analyst, environmental regulations in place to prevent the types of discharges that occurred during Hurricane Katrina were not enforced, making what would have been a bad situation much worse. Unchecked development throughout ecologically sensitive parts of the region put further stress on the environment’s ability to absorb and disperse noxious chemicals. “Folks down there were living on borrowed time and, unfortunately, time ran out with Katrina,” Kaufman concludes.

As Hurricane Katrina Cleanup Continues, Region Braces for Next Wave

Recovery efforts first focused on plugging leaks in levies, clearing debris and repairing water and sewer systems. Officials cannot say when they will be able to concentrate on longer-term issues such as treating contaminated soil and groundwater, though the U.S. Army Corps of Engineers has been deploying Herculean efforts to physically remove tons of contaminated sediment left behind by receding floodwaters. 

Ten years later, massive restoration efforts are underway to reinforce the coast's natural defenses against large storms.

Yet every spring, residents living near the Gulf Coast keep a wary eye on the forecast, knowing that a new, freshly brewed storm might bear down. With hurricane seasons potentially influenced by increasing ocean temperatures due to global warming, it should not be long before the new coastal restoration projects are tested.

Edited by Frederic Beaudry