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Environmental Sample Processor monitors drinking water in Lake Erie

Environmental Sample Processor monitors drinking water in Lake Erie

This satellite view shows a large algal bloom in Lake Erie during 2011. The algae in some blooms produce toxins that threaten drinking-water supplies for cities such as Toledo, Ohio. Image courtesy of the National Oceanic and Atmospheric Administration.

When MBARI scientists and engineers design instruments for studying the ocean, they never know where these instruments will end up. A case in point is the Environmental Sample Processor (ESP), an automated, robotic “microbiology laboratory in a can.” ESPs were originally designed to study toxic algal blooms in the ocean, but they are now being used to protect municipal drinking-water supplies.

In July 2017, researchers deployed an ESP nicknamed “ESPNiagara” on the floor of Lake Erie, about 6.5 kilometers (four miles) west of the main drinking-water intake for the city of Toledo, Ohio. Each day or two it analyzes water samples for a toxin called microcystin, and sends the results to researchers on shore.

Many cities around the Great Lakes pump their drinking water right out of the nearest lake. This vast source of fresh water is a blessing, but can become a curse when toxin-producing cyanobacteria (formerly known as “blue-green algae”) become abundant during the summer months. In August 2014, one of these toxic algal blooms left 400,000 people in the Toledo area without safe drinking water for two days.

Because of these blooms, researchers around the Great Lakes have been monitoring lake water for harmful algae and the toxins they produce. Currently, water samples are collected once a week and then analyzed in the lab—a process that can take 24 to 48 hours. This lag time increases the chance that the public could be exposed to dangerous levels of algal toxins. In contrast, the ESP can collect water samples hourly or daily, and send results back to shore in just two or three hours.

MBARI Senior Research Technician Roman Marin III (left) and a NOAA researcher prepare to deploy ESPNiagara in Lake Erie. Image courtesy of Tim Davis, NOAA.

Although MBARI developed the first ESPs, these versatile instruments are now being manufactured and sold by a private company, McLane Research Laboratories, for use by scientists and resource managers around the country. The latest ESP deployment is a joint project of the National Oceanographic and Atmospheric Administration (NOAA), the Cooperative Institute for Great Lakes Research (CIGLR), the University of Michigan, and MBARI. NOAA and CIGLR purchased ESPNiagara from McLane using federal funds from the Great Lakes Restoration Initiative.

Roman Marin III, a senior research technician at MBARI, traveled to Lake Erie to help with the deployment. He worked closely with CIGLR research technician Emily Davenport, who will be maintaining the system. Davenport said, “I’m really proud to be working in Great Lakes water quality research, because it benefits people’s lives in a way that’s tangible. Sometimes it can be really hard to communicate the importance of science to the general public, but not in this case. We all need clean water.”

The recent ESP deployment is just one part of a large-scale, multi-year effort by CIGLR to study harmful algae in the Great Lakes using satellite imagery, genetic studies of cyanobacteria, field sampling, and public outreach. NOAA and CIGLR researchers have already developed computer models that can predict when algal blooms are likely to occur. But they cannot yet tell whether these blooms will consist of toxic species of cyanobacteria.

NOAA plans to deploy two more ESPs in the Great Lakes next year. The resulting network of three toxin-monitoring ESPs will help researchers refine a computer model to predict not just when blooms are likely to occur, but also how toxic they are likely to be.  MBARI researchers are also planning to deploy another ESP on an underwater robot that will swim around the lake monitoring microcystin over large areas.

Last year, one of MBARI’s underwater robots, a long-range underwater vehicle, proved its usefulness for studying plankton (microscopic animals and algae) in Lake Michigan. This year the ESP is providing Great Lakes researchers with another tool to understand some of the largest bodies of fresh water on the planet. These projects show how MBARI technology originally designed for oceanographers can serve a variety of uses, both in and out of the ocean.

Article by Kim Fulton-Bennett

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