University of Michigan researchers and their colleagues have issued a forecast for a significant bloom of toxic blue-green algae in Lake Erie late this summer.

The predicted 2014 Lake Erie harmful algae bloom is expected to be larger than average but considerably smaller than the record-setting 2011 event, according to U-M aquatic ecologist Don Scavia and colleagues from the federal government and several universities.

An algae bloom is a rapid buildup of algae in a body of water, and harmful blooms are those that damage other organisms — including humans — through the production of toxins or by other means. Agricultural practices in the watersheds that feed into western Lake Erie provide phosphorus and other nutrients that fuel large-scale algae blooms.

“Until we reduce the flow of nutrients from croplands into the lake, large algae blooms will likely continue to plague Lake Erie,” said Scavia, director of the Graham Sustainability Institute.

Bloom impacts will vary this summer across the lake’s western basin and are classified by an estimate of both the biomass (cell concentration) and the spatial extent of the bloom. This marks the third time the U.S. National Oceanic and Atmospheric Administration and its partners have issued an annual outlook for western Lake Erie.

Harmful algae blooms were common on western Lake Erie from the 1960s to the 1990s. After a lapse of nearly 20 years, they have been steadily increasing over the past decade.

Since 2008, NOAA has issued weekly harmful algae bloom bulletins for western Lake Erie as an early warning system to track bloom development. The weekly bulletins will continue in 2014.

“The Lake Erie harmful algal bloom forecast, combined with NOAA’s weekly HABS Bulletin, underscores the importance of having accessible and usable environmental intelligence to inform decisions of public and environmental health,” said Kathryn D. Sullivan, undersecretary of commerce for oceans and atmosphere and NOAA administrator. “As an Ohio native, I understand the importance of these ecological forecasts to the Great Lakes region and its economy.”

“This NOAA model, resulting from a great collaboration, has been incredibly valuable to us as we work to eliminate blooms to protect human health, the Lake Erie ecosystem and its coastal economy,” said Jeff Reutter, director of Ohio State University’s Sea Grant program and Stone Laboratory.

“In Ohio, as part of the Ohio Phosphorus Task Force II, we have used information from the NOAA model to help us target reductions in the amount of phosphorus going into the lake that should help us greatly reduce or eliminate the HABS.”

Blooms of blue-green algae can produce toxins that may taint drinking water and recreational water. People who drink or swim in water that contains high concentrations of these algae or the toxins may experience gastroenteritis, skin irritation and allergic responses, according to the U.S. Centers for Disease Control and Prevention.

In addition, algae blooms can foul harbors, clog boat motors, reduce fish populations and sometimes lead to the formation of low-oxygen “dead zones” where most aquatic life cannot survive.

The 2014 Lake Erie seasonal forecast is based on two computer models, one developed by NOAA and the other a jointly funded effort of the U-M Water Center and NOAA’s Great Lakes Environmental Research Laboratory in Ann Arbor.

The forecasts use a 12-year Lake Erie nutrient-flow data set collected by Heidelberg University’s National Center for Water Quality Research, analysis of satellite data from the European Space Agency’s ENVISAT and NASA’s Terra and Aqua satellites, and in-lake measurements from the University of Toledo.  ​

In addition to the satellite monitoring of the lake, NOAA’s Ann Arbor lab, Ohio State University’s Sea Grant Program and Stone Laboratory, Heidelberg University, the University of Toledo and the Ohio Environmental Protection Agency will collect key measurements from the lake as the summer progresses. That information will be shared with regional managers and will help NOAA scientists further refine the forecast models.

“Issuing and evaluating these seasonal forecasts improves our understanding of how the blooms form, which leads to strategies to reduce their impacts,” said Richard Stumpf, NOAA’s ecological forecasting applied research lead.

“The academic partnerships we have support not only this forecast, but also help managers to monitor the bloom through the season and inform the public of when it is safe to use Lake Erie resources.”

The research programs supporting this work are authorized under the Harmful Algal Bloom and Hypoxia Research and Control Act, known as HABHRCA, which was amended and reauthorized by Congress in June through 2018.