High-tech buoys monitor water cleanliness in real time to protect health of beach-goers.
The sensor-fitted buoys, developed by a team from Michigan State University (MSU) and the US Geological Survey, have been deployed at several beaches of Lake Michigan in Chicago to provide data on various contaminants, including bacteria E. coli.
"Current beach-management practices are slow and unreliable," said Phanikumar Mantha, an MSU professor of civil and environmental engineering and a member of the research team. "A water sample needs to be gathered, then taken to a lab for analysis. That can be anywhere from 24 to 48 hours. If you go to the beach today and swim, then you find out tomorrow you shouldn't have gone, that's not very helpful."
The buoys measure multiple parameters of water quality, including temperature, clarity and chemical composition and share the information in real time with beach-managers using an on-board modem. The buoys run complex algorithms to extract specific data and can focus on a particular type of contamination, which might be of interest at a given time.
"That can have a real effect on local economies," Mantha said. "If you close a beach unnecessarily, it's hurting the local businesses."
Data from the buoys help those responsible for managing the beaches to make better decisions when deciding whether it is necessary to restrict access to water and ban swimming. The systems on the buoys can also automatically disseminate the information to the public via websites.
“Our ultimate goal is to protect the public from getting exposed to contaminated water," Mantha said. "This problem can be particularly hard on children and seniors, who tend to be more susceptible to its dangers."
Details of the research have been published in the journals Environmental Science and Technology and the Journal of Environmental Management.