Summer is upon us, and that means one frightening truth for those living around the Great Lakes; soon, their water will start turning disturbing greens, browns, and reds. Soon, signs will start appearing at your favorite watering holes that advise against swimming. And for Lake Erie, the worst harmful algae bloom (HAB) ever measured might be right around the corner.

So what exactly is a HAB? Every summer freshwater cyanobacteria (aka: blue-green algae), and related saltwater "Red Tides" approach their natural growing seasons, blooming en masse and releasing minute levels of microcystin. Traditionally, the concentration of this natural toxin never reaches levels that could harm humans or even most wildlife. However, in recent years, the NOAA and independent parties have determined that between unchecked agricultural practices, long winters, and rainy springs, algea populations can dangerously spike just before a bloom.

"Excessive runoff is feeding an explosion of toxic algae that is choking our waters, closing our beaches, and posing a threat to people, pets, and wildlife. This is a national problem that demands a national solution," Andy Buchsbaum, the regional executive director of the NWF's Great Lakes Regional Center, said in a 2013 report issued by the National Wildlife Federation (NWF). (Scroll to read on...)

What's worse, experts determined just last year that climate change may be exacerbating this situation. Warming surface temperatures, it seems, are not only ideal for blue-green algae growth, but are also welcoming for invasive quagga and zebra mussels. These mollusks are reportedly feeding on types of algae that are typically good for the Great Lakes, while utterly ignoring cyanobacteria - leaving them to wreak havoc on water quality.

The result? With these factors only getting worse, the NOAA and its university research partners have determined that the 2015 western Lake Erie HAB season will be among the most severe ever seen - a probable 8.7 on the severity index. Experts are predicting that the severity of toxin concentrations could even get as bad as a 9.5, with a perfect 10 being the highest level ever seen (recorded in 2011). (Scroll to read on...)

"This is the fourth seasonal harmful algal bloom outlook for Lake Erie that NOAA has issued," Holly Bamford, an assistant NOAA administrator for the National Ocean Service explained in a statement. "NOAA's ecological forecasting initiative... provide[s] science-based information that water managers, public health officials, and others need to make critical decisions to protect the health of their communities, understand environmental impacts, and mitigate damages to recreational activities that are a vital part of the region's economy."

Specifically, the review and ongoing investigations will be aimed at ensuring that a repeat of the Toledo, Ohio water quality crisis never occurs. Just last year, the city had to declare a state of emergency after the great majority of its water supplies became overwhelmed with microcystin, rendering all drinking water in the region unsafe

Amazingly, this was when the Lake was experiencing a summer bloom that only approached 6.5 on the net severity index. However, anything above a 5.0, according to the NOAA, is of "particular concern." (Scroll to read on...)

"While this year's toxic algae forecast for Lake Erie calls for a bloom larger than the one that shut down the Toledo area's water supply last summer, bloom predictions--regardless of size--do not necessarily correlate with public health risk," University of Michigan aquatic ecologist Don Scavia, a member of the 2015 forecast team, added reassuringly.

"But we cannot continue to cross our fingers and hope that seasonal fluctuations in weather will keep us safe," he went on, calling specifically for strong agricultural reforms to reduce algae-feeding runoff from over-fertilizing.

"These blooms are driven by diffuse phosphorus sources from the agriculturally dominated Maumee River watershed," he explained. "Until the phosphorus inputs are reduced significantly and consistently so only the mildest blooms occur, the people, ecosystem and economy of this region are being threatened."

To provide more real-time information during the bloom season, NOAA has produced harmful algal bloom (HAB) bulletins for western Lake Erie since 2008. The bulletins will continue twice-weekly and can be received by a subscription to the NOAA Lake Erie HAB Bulletin.

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