Great Lakes buoys help fight algal blooms, and they just returned to the water

(FOX 2) - 'Tis the season when rain pours, temperatures rise and buoys return to the Great Lakes.

That means the return of hourly weather data vital to understanding the conditions of the lakes. By the beginning of summer, more than 30 of the bobbing pillars will be dragged out to their specific locations, where they'll be reattached to underwater cables.

“That data is used to help inform marine forecasting models and wind and wave and currents we forecast,” said Tom Johengen, a researcher at the Cooperative Institute for Great Lakes Research (CIGLR). “Those obviously benefit anyone out and about.”

All that basic weather data that makes it to your weather channel starts with buoys in the water. Temperature readouts and wind speeds help meteorologists make better predictions about what your daily forecast will look like.

However, the buoys have recently been recruited for a more nuanced purpose: analyzing algal blooms. The plague of green goo that covers much of Lake Erie and parts of Saginaw Bay have created problems for boaters, scientists and anyone else that uses the water.

Since 2015, these buoys have been modified to detect the amount of phosphorus in the water, one of the main ingredients that catalyze the harmful algal blooms.

“These buoys measure chemistry,” said Steve Ruberg, with the Great Lakes Environmental Research Laboratory (GLERL). “Measuring the amount of phosphorus in the water helps us understand harmful algal blooms.”

There are six of these buoys in Lake Erie that help pass along this information. Some manned by CIGLR and NOAA, while some are deployed by Canadian-related agencies. Worth about $50,000, it takes roughly another $50,000 for operation costs.

Algal bloom events are common in lakes that border land used for agricultural and recreational purposes. In recent years, the events have become so extreme they have been observed from orbiting satellites. They occur when a surge of nutrients like phosphorus and nitrogen enter the water, where the provide fuel for rapid growth of algae.

When blooms become big enough, they can injure animals and modify a water's ecology by absorbing the oxygen in the water and blocking sunlight from reaching the vegetation on the bottom of the lake. In one 2014 event, an algae bloom was so extreme it poisoned the water system connected to Toledo, Ohio, which was used by 500,000 people.

Lake Erie is a hot bed for bloom events due to the amount of agricultural and urbanized land near the lake. While there is already phosphorus in the sediment on the lake bed, much of what spurs a bloom comes from the phosphorus dumped into the lake by the Maumee River. Drawing that distinction is important - which is where Lake Erie's buoys come from.

“These buoys help us separate the two things,” Ruberg said. “What the buoys help us understand is how much phosphorus comes from the Maumee River. It has the most concentrated phosphorus (of any river).”

There's already phosphorus in the lake. But understanding how much more is added from the river helps scientists further understand the impact from land used by manufacturers and farmers. Ruberg said if the amount of the known- phosphorus in the lake is changing, that can help indicate how extreme the bloom will be in the summer.

With that information, stakeholders can better predict how their business will work as well.

“...that lets drinking water managers know things are doing as far as harmful algal bloom seasons go,” Ruberg said. “It makes them more aware for processing water.”

That information can also better help inform which control measures would be best for limiting nutrients entering the water. That's why Ruberg said “the number one benefactor of buoy data is the public.”

Buoys have always served a public-service, although their purpose has changed and grown. Initially added as visual aids for navigation, they have become some of the most important sources of information in the water. The complexity of that information they record has also grown, and doesn't just include algal bloom nutrients.

The buoys in Lake Michigan have been focused on gathering biological information like the water. Due to concerns about declining activity in lakes that may impact the state's fisheries, information on phytoplankton is being collected to get a better idea of the changing biomass in the state.

That information is not reserved for one party. While the Great Lakes buoys are owned by a variety of entities, both private and public, all of the information gathered is collected by the Great Lakes Observing System. From there, that information is disseminated to anyone who uses it.

“Not surprisingly, the people that go to the beach or fish love that information,” Ruberg said. “That's why we put more routine and reliable information out there.”

It's not just the current conditions that are important to know, however. Ruberg also said that looking at those observations helps plan for the future - a necessity considering the changing state of the Great Lakes.