By Peter Chawaga
Lake Erie might be ground zero for harmful algal blooms. In possibly the most infamous instance of toxic algae, Toledo residents were unable to access their drinking water because of a bloom there. Since then, the problem has only gotten worse, reaching record levels in the lake.
While the situation seems desperate, Lake Erie’s dire straits are also an opportunity to make it a point of progress against the threat. A new program from NASA might jumpstart a cutting-edge turnaround.
NASA’s Glenn Research Center has been using hyperspectral imagers mounted to manned aircraft in order to monitor toxic algal blooms in Lake Erie for several years, according to Roger Tokars, an engineer in the center’s optics and photonics branch. This month, it miniaturized its sensing equipment so that it could monitor the blooms from unmanned drones, a potential big step forward in the program.
“Drones provide high-resolution mapped images of smaller targets such as rivers, streams, and around specific waypoints,” said Tokars. “Additionally, the portability and ease of use could allow for a researcher or water monitoring personnel to quickly and easily map out an area close at hand. …A drone program builds upon [the manned flights] by giving an additional option at our disposal that can be used below the clouds, with high resolution and easier, more flexible deployment.”
NASA’s hyperspectral development team, led by Dr. John Lekki, teamed up with a group of young Glenn Research Center engineers known as “Rocket University” for the project, which they called Hydrus. The NASA group teamed with Sinclair Community College, which provided an Altavian NOVA F6500 drone as the platform for the miniaturized spectrometer.
Researchers can use aerial photographs to find out where blooms are forming or need to be cleaned up and to conduct quantitative analysis to estimate the level of cyanobacteria and sediment in the water.
“The instruments that researchers at NASA Glenn are developing really let us quantify the amount and type of material present in the bloom,” said Dr. Joseph Ortiz, a professor at Kent State University who has been working with NASA and researchers from the university consortium OhioView on this project since 2014. “By knowing how thick the bloom is and where it is located, we can direct ground crews to take samples to verify what is there and assess the risks to the public and both private and commercial assets in the area. We can also try to determine where the bloom may have originated from.”
Ortiz added that the images could provide a warning to drinking water treatment plants when there is a bloom coming their way and whether or not it is toxic, which might help them manage the treatment process more effectively.
“Immediately mapped algal data of areas where the water treatment operator is working can provide valuable information of the area around them to allow them to take steps necessary to manage the quality of water in their intakes,” said Tokars.
The benefits of the drone-powered monitoring program are straightforward, as access to more information always allows for better preparation, but funding for such an ambitious initiative won’t be easy to come by.
“Continued funding to continue improving our method and to allow us to develop new methods and ideas is always a challenge,” said Ortiz, adding that in addition to support from NASA, he has received funding from the Ohio Sea Grant and the Ohio Department of Higher Education. “With continued support, we will make great strides in addressing this problem.”
The hope is that the trial’s success will mean more opportunity to monitor algae this way.
“NASA Glenn does not currently fund a drone program, although it is hoped that this early, successful demonstration of the use of drones with NASA technology may lead to future funding in subsequent years,” said Tokars.