New details: Dayton water plant flooded in Memorial Day tornadoes

City still evaluating costs after 12-14 feet of water invaded plant.

One of Dayton’s two drinking water treatment plants flooded during the Memorial Day tornado outbreak, the Dayton Daily News has learned.

The Ottawa Treatment Plant basement flooded with 12-14 feet of water just before midnight on May 27, according to a document the Dayton Daily News obtained from the city as part of a public records request.

The plant at 1044 Ottawa St. couldn’t distribute water into the system due to the power outage, causing the flooding, city spokeswoman Toni Bankston said in a statement to the newspaper.

DETAILS: Contaminants in Dayton water above what some states consider safe

“Some electrical components were damaged,” Bankston said. “These have either been repaired or are in the process of being repaired. We are still evaluating costs.”

The Ottawa plant “has continued to operate, meeting all regulatory compliance during these repairs,” Bankston said. She declined to release photos of the damage, citing unspecified security reasons.

The city’s other water treatment facility, the Miami Treatment Plant at 3210 Chuck Wagner Lane, did not experience any flooding, she said.

The document obtained by the Dayton Daily News is a city-created timeline that gives a detailed moment-by-moment account of the city’s handling of an unprecedented event: the loss of power to two water treatment plants that caused the city’s drinking water system to fail.

That led to a system-wide boil advisory, the second such advisory issued this year after a large break in a main pipe in February caused a loss of pressure in the system.

RELATED: Ohio EPA declines to mediate Dayton, Montgomery County water talks

The record, which refers to the outbreak of 15 tornadoes as “mayhem,” reveals that the two plants lost power within five minutes of one another on May 27.

At 11:13 p.m., the Mad River well field operator notified the supervisor that the power was out but the operator “could not leave (the) building to assess damage due to severity of the storm.”

By 11:50 p.m. May 27, about 35 minutes after the plant lost power, the Ottawa plant operator notified the water division manager that flooding had been discovered.

By midnight, the plant electrical engineer called a vendor to replace electric motors at the plant. At five minutes after midnight, electricians opened the main breaker and isolated the plant from the rest of the Dayton Power & Light electrical feed.

Ten minutes later, plant employees had set up a diesel pump and began removing water from the plant. A second pump was added a half-hour after the first began pumping, the record says.

The city’s timeline also says city staff members contacted area hospitals multiple times throughout the night to keep them updated.

DP&L restored electricity to the Ottawa plant and pump station about 10:30 a.m. May 29.

The record says the city acquired rental dehumidifiers on May 30 for use at the plant, and the next day installed heaters in the basement. The boil advisory in place following the loss of water pressure was fully lifted May 31.

Read more coverage from the Dayton Daily News:

» County alleges city water issues put community at risk

» Understanding Dayton’s drinking water issues

About the Author