Toledo Water Clears, but Outlook Is Cloudy

Restrictions Are Lifted After Two Days, But Algae Blamed for Ban Could Worsen.

A wave of relief washed over this city Monday after its mayor rescinded a two-day-old restriction on a drinking-water supply serving 500,000 people.

But the good news for residents could be clouded by the forecast from some scientists who suspect the responsible toxin in the drinking water came from a large, soupy-green algal bloom on Lake Erie near the city. The bloom may not peak until September, and in-lake conditions are likely to worsen over the next month, according to Don Scavia, aquatic ecologist and director of the University of Michigan’s Graham Sustainability Institute, who helped issue the forecast of a harmful algal bloom for the lake last month.

Experts also said a large bloom doesn’t necessarily lead to high levels of the toxins in the water used for drinking. Much depends on the quality of the water at the intake point, often deep below the surface where the algae bloom usually resides.

Still, D. Michael Collins, the mayor of Toledo, raised a glass of city tap water and drank it outside the county emergency-management center Monday morning as a sign to the city and its suburbs that the water was now safe to drink. He added that the city had already employed new water-treatment measures, including adding chlorine and carbon, to try to reduce the toxin. “Here’s to you, Toledo,” Mr. Collins said. “You did a great job.”

Officials and water experts over the weekend said that much more will likely need to be done to reduce the toxin’s suspected cause: nitrogen and phosphorus in Lake Erie, which can come from runoff of overfertilized fields and lawns; from malfunctioning septic systems; and from livestock pens.

“Farmers have changed a lot in the last 10 years in terms of pollution. We know these issues better than most people, and we want to protect the lake,” said John Myers, a 69-year-old grain farmer just north of Toledo who brought truckloads of safe well-water to city residents over the weekend.

Other factors are also at play, including climate change and invasive mussels, according to Gary Fahnenstiel, research scientist at the University of Michigan Water Center. Those factors change the way the lake responds to the nutrients flowing into the lake from croplands, he said in a statement Monday.

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