In Rural Illinois, Solar Powered Ultrasound Helps Kill Toxic Algal Blooms
Mattoon, Illinois relies on Lake Paradise for drinking water, and since 2019 has deployed solar-powered buoys called Solarafts that blast cyanobacteria with ultrasonic waves to prevent toxic algal blooms. The system failed last year when two of three buoys were chewed up by muskrats and sat offline until June, by which point warm weather and drought-shrunk, stagnant water let cyanobacteria flourish, forcing a “do not drink” order in July 2025 after toxin levels spiked.
The plant responded by quadrupling its carbon treatment, from 150 to 600 pounds a day, to get the bloom under control before leaning on the buoys again. Officials point to fertilizer runoff from surrounding farmland, plus everyday contributors like lawn fertilizer, detergent and human waste, as sources of the phosphorus and nitrogen that feed the bacteria, with the same runoff eventually reaching the Mississippi basin and the Gulf of Mexico dead zone.
The manufacturer, Hydro-Bioscience, says the ultrasonic approach cuts chemical use by roughly half and is now adding remote water-quality monitoring tools so plant staff can track conditions without constant manual sampling.
The full dispatch is available from the source below.