City officials continue to monitor the blue-green algae bloom which has caused the closure of the upper reservoir at Veterans Memorial Lake Park.
"It took two hours to treat it," said Josh Snyder, public works director.
"The algae seems to be receding and coming closer to the shore," he added. "It's breaking up."
Crews are treating the upper reservoir with copper sulfate.
New water samples are being taken to The Ohio State University Lab on an island in Lake Erie for testing, Snyder said. The first samples taken to the lab Monday tested positive for harmful toxins caused by the algae.
The city's drinking water supply is safe, according to Snyder, as that water comes from the lower reservoir.
What caused the blue-green algae to form in the upper reservoir?
"That's probably of great interest to the EPA (Environmental Protection Agency)," Snyder said.
"The reservoir is basically fed from the Norwalk Creek and that is fed from fields mainly east of the city limits," he added.
To read full story see today's Norwalk Reflector.