Toledo's mayor says some 400,000 regional residents should continue to find other sources for drinking water.
Tests showed on Friday that the city's water supply contained toxins, possibly from cyanobacteria in Lake Erie.
The Toledo Blade reports Mayor Michael Collins said at a news conference today that water samples are improving, but he didn't give the all-clear for water consumption or for cooking.
"We have some results, but not enough to go by," he told reporters outside the Lucas County Emergency Services Building. "All of the results continue to improve. We have more below-detectable levels (of toxic microcystin) than we had before. This is not over yet, though."
Ohio Gov. John Kasich is expected to arrive in Toledo this afternoon to help review the results of the latest water tests conducted by the Environmental Protection Agency.
The Toledo Blade says city and county officials have set up water distribution centers in the region, and some 33,000 gallons of drinkable water have been provided by the Ohio National Guard.
Area retailers are also working to restock their water supplies after they were cleaned out Saturday. Some Toledo residents traveled to nearby Michigan communities to find water.
Going out for a meal has also been complicated by the water alert: Restaurants have been asked to stay closed unless they have enough bottled water for cooking, food preparation and washing dishes.
Clarification: An earlier version of this story referred to "algae blooms" in Lake Erie. These are really bacterial blooms (cyanobacteria) that look like algae. The copy has been clarified above.