Climate

Lake Erie’s Enormous Algae Bloom Is Back

CREDIT: AP Photo/Haraz N. Ghanbari, File

A 2014 algae bloom covers Lake Erie near the City of Toledo water intake crib.

For the second year in a row, a harmful algae bloom is beginning to form in Lake Erie — and the National Oceanic and Atmospheric Administration has predicted that this year’s algae bloom could rival that of 2011, the most severe bloom on record.

During that record bloom, close to 20 percent of Lake Erie was covered by a green-tinged algae — technically cyanobacteria, a type of aquatic bacteria that uses photosynthesis to create energy and thrives in warm conditions. In a 2013 Ecowatch report, scientists from Oregon State University called it “the cockroaches of the aquatic world.”

This is the same type of algae that disrupted the Ohio city of Toldeo’s water supply for three days last summer, prompting officials to issue a tap water ban. In large amounts, an algae bloom can produce a harmful toxin known as microcystin, which, if consumed, can cause dizziness, nausea, vomiting, diarrhea, and liver damage. Boiling doesn’t kill the toxin — it just makes it worse.

“Last summer’s Toledo water crisis was a wake-up call to the serious nature of harmful algal blooms in America’s waters,” Jeff Reutter, senior advisor to Ohio State University’s Sea Grant program and Stone Laboratory, said at a NOAA press conference in July. “This forecast once again focuses attention on this issue, and the urgent need to take action to address the problems caused by excessive amounts of nutrients from fertilizer, manure and sewage flowing into our lakes and streams.”

In the years following World War II, factories dumped huge amounts of phosphorous-laced waste water into the Great Lakes, spurring algae blooms and widespread pollution. The Clean Water Act curbed some of that pollution, and for a time the health of the Great Lakes seemed to be on the mend. But industrial farming, which brings with it huge amounts of fertilizer runoff from corn and soybean operations, is at least partly responsible for a recent surge in algae bloom activity in the Great Lakes region. Of all the phosphorous that makes its way into the Lake Erie Basin, 61 percent of it comes from cultivated cropland.

But increased phosphorous from commercial agriculture might be just one factor in Lake Erie’s algae uptick. Timothy Davis, a NOAA research ecologist specializing in harmful algae blooms, told National Geographic that some of the recent increase in blooms “can be attributed to global climate change.” That’s because the bacteria responsible for the blooms thrive in warm temperatures — something that climate change is helping create.

Climate change is also predicted to increase the intensity of rainfall and flooding that occurs around the Great Lakes in the coming decades, something that could lead to more phosphorus from fertilizer being washed into waterways instead of absorbed into cropland. Phosphorous can also make its way into waterways from leaky septic tanks and aging stormwater and sewage infrastructure. An increase in precipitation could overwhelm this infrastructure — especially those which combine stormwater and sewage in the same system — pushing more nutrients from sewage into waterways where it can feed algae blooms.

Earlier this year, 18 international researchers published a study in Science arguing that human activity has already pushed the planet beyond four of nine environmental boundaries, making the planet less hospitable to life in the process. One of these boundaries that had been crossed was biogeochemical flows — nitrogen and phosphorus cycles that have been disrupted in large part due to fertilizer overuse and mismanagement.

“For the first time in human history, we need to relate to the risk of destabilizing the entire planet,” Johan Rockstrom, one of the study’s authors, told Reuters after the study’s publication. “We are at a point where we may see abrupt and irreversible changes due to climate change.”

So far, the 2015 algae bloom underway in Lake Erie hasn’t caused any public health scares — according to a report in Bridge Magazine, Toledo officials found small amounts of microcystin at the city’s water intake cribs, but the levels were not high enough to prompt a tap water ban. Still, some residents — frightened by the magnitude of last year’s bloom — are stocking up on bottled water, calling another bloom “inevitable.” The city has since installed an early warning system near its intake as well as a filtration system, leading some residents to express renewed trust in Toledo’s ability to handle algae blooms.

The Great Lakes aren’t the only place battling an increase in algae blooms, however. According to the Environmental Protection Agency’s most recent National Lakes Assessment, nearly one-quarter of all lakes sampled for cyanobacteria presented moderate or high risks to cyanotoxins like microcystin. Around the world, algae blooms are on the rise, popping up in places like Brazil, China, and Australia.