Site predicts Maumee Bay park water quality

Before heading out to Maumee Bay State Park for a day at the beach, make sure to check the Ohio Nowcast Web site for daily forecasts of water quality.

"The Nowcast predictive model is the latest advance in ongoing efforts to keep the public safe from pollution at the beach," said Pam Struffolino, a researcher at the University of Toledo's Lake Erie Center.

The site, ohionowcast.info, announces swimming advisories based on the likelihood that E. coli in the water exceeds safe levels. So far this month, the site has posted three warnings to beach-goers to stay out of the water at the Oregon park. Thursday's report indicated that water quality was good.

"We try to have the results up before 9:30 a.m. to inform people before they leave the house," Ms. Struffolino said. Early each morning, a UT student measures the temperature and clarity of the water, counts the number of birds on the beach, and collects data on other environmental factors.

The forecasting system also takes into account such information as rainfall, wind speed, and levels of solar radiation. "Then we run our data through the model to see what prediction it will give," Ms. Struffolino said.

That process takes about an hour. Typically, laboratories would measure the E. coli level by straining a sample of lake water through a membrane, incubating it in a warm, damp petri dish for roughly 24 hours, and then counting how many bacteria colonies have grown.

"The traditional methods are not as efficient," Ms. Struffolino said. They also produce E. coli predictions based on water samples taken from the previous day, but E. coli levels change from hour to hour. A sudden rainstorm, for example, may cause E. coli levels to rise dramatically.

Ms. Struffolino maintains that Nowcast works just as well as or better than estimating the public health risk by measuring the previous day's E. coli. Three years of weather and environmental data went into the Nowcast model for Maumee Bay State Park, tailoring it to that beach's specific conditions.

At Huntington Beach in Bay Village, Ohio, near Cleveland, Nowcast predictions have been correct 84.2 percent of the time since 2006, according to the Web site.

UT works in conjunction with agencies including the U.S. Geological Survey and the Ohio Department of Health to operate Nowcast. USGS plans to set up similar forecasting systems, which save labor and cut costs, at 50 more sites throughout the Great Lakes region.

Contact Sophie Broach at: sbroach@theblade.com or 419-724-6210.