MIDLAND, Mich. (AP) — Floodwaters have overtaken dams and forced the evacuation of about 10,000 people from communities in central Michigan, where the governor warned that Dow Chemical Co.'s hometown could end up under 9 feet of water by Wednesday evening and said the state will investigate the dam operators.

Families living along the Tittabawassee River and connected lakes in Midland County were ordered to leave home Tuesday evening, the second time in less than 24 hours. By Wednesday morning, water several feet deep covered streets, parking lots and parkland and had reached a hotel near the river in downtown Midland.

No injuries or fatalities related to the flooding have been reported, city spokeswoman Selina Tisdale said.

The river topped a previous record of 33.9 feet (10.3 meters) set during flooding in 1986, the National Weather Service said. Its flood stage is 24 feet (7.3 meters), and it was expected to crest by day's end at about 38 feet (11.6 meters).

The Weather Service urged anyone near the river to seek higher ground following “catastrophic dam failures” at the Edenville Dam, about 140 miles (225 kilometers) north of Detroit, and the Sanford Dam, about seven miles (11 kilometers) downriver.

Midland City Manager Brad Kaye said Wednesday that the Sanford Dam is overflowing but the extent of structural damage isn't yet known.

If the entire dam structure were to fail, “there would be a much higher surge that will come down the river and that could raise the level much more quickly than what we’re seeing right at the moment," Kaye said.

Michigan is under a stay-at-home order to prevent the spread of the coronavirus. While Michigan has been a national hot spot for COVID-19, with more than 52,000 cases and 5,000 deaths, Midland County has had fewer than 80 cases and under 10 deaths. Still, residents were advised to take precautions and area schools set up as shelters spaced cots to adhere to social distancing guidelines.

Gov. Gretchen Whitmer said downtown Midland, a city of 42,000 and home to Dow Chemical Co., faced an especially serious flooding threat.

“In the next 12 to 15 hours, downtown Midland could be under approximately 9 feet of water,” the governor said during a late Tuesday briefing. “We are anticipating an historic high water level.”

On Wednesday, Whitmer told reporters that her office has been in touch with the federal government and will ask FEMA for support. “This is an event unlike anything we’ve ever seen before,” she said.

President Donald Trump tweeted that he was closely monitoring the situation and praised first responders. But he also took a jab at Whitmer, whom he has criticized for her stay-at-home orders: “We have sent our best Military & @fema Teams, already there. Governor must now ‘set you free’ to help. Will be with you soon!”

Whitmer said the state would investigate the operators of the dams and “pursue every line of legal recourse we have.”

The Federal Energy Regulatory Commission said it has directed Boyce Hydro to establish an independent investigation team to determine the cause of the damage to Sanford Dam, and that it would reach out to state officials regarding the Edenville Dam. It will send an engineer to assist with the investigation when it’s safe to do so.

In 2018, the commission revoked the license of the company that operated the Edenville Dam due to non-compliance issues that included spillway capacity and the inability to pass the most severe flood reasonably possible in the area.

In 2018, the state rated the Edenville Dam, which was built in 1924, in unsatisfactory condition. The Sanford Dam, which was built in 1925, received a fair condition rating. Both are in the process of being sold.

“The initial readout is that this was a known problem for a while and that’s why its important that we do our due diligence," Whitmer said.

Dow Chemical, with 9,000 employees and contractors in Midland, on Tuesday shut down all operating units except those needed to contain chemicals, spokesman Kyle Bandlow said. By Wednesday, floodwater was mixing with on-site containment ponds prompting the company and U.S. Coast Guard to activate emergency plans, Dow said in a statement. Only essential staff was on site and no injuries have been reported, the company said.

The flooding will likely pose a significant setback to the cleanup of a federal Superfund site caused by Dow’s release of dioxins in the last century, which contaminated sediments and floodplains along 50 miles (80 kilometers) of the Tittabawassee and Saginaw rivers to Lake Huron’s Saginaw Bay, said Allen Burton, a professor of environment and sustainability at the University of Michigan.

Dow and the state Department of Environment, Great Lakes and Energy will have to determine where the floodwaters have moved the dioxins, Burton said.

“They knew where all that stuff was, but the power of water is unbelievable and it’s going to move things around," Burton said.

Dow Chemical. has been headquartered in Midland for more than 120 years, and its main plant sits on the city’s riverbank. It is a quintessential company town: One high school is named after the company’s founder, the other high school’s mascot is the Chemics. A Dow foundation has funded many community amenities including a botanical garden, and the city is known for its midcentury modern structures first introduced by architect Alden B. Dow.

Steve Carlson, 61, said he and his wife, Patty, fled their Midland home about 8:30 p.m. Tuesday after an evacuation order was issued for much of the city, and they noticed neighborhood creeks were spilling over local roads and threatening some homes.

“They had risen a lot and the worst was yet to come,” Carlson said Wednesday morning.

One couple in their neighborhood decided to stay put, but Carlson said everyone else has left. The Carlsons spent the night in a hotel.

Further down the Tittabawassee River, communities in Saginaw County were on alert for flooding.

“It's going to continue downriver,” Sara Pampreen, a weather service meteorologist, said. “Just exactly how much, that’s the question.”

Whitmer declared a state of emergency for Midland County and urged residents threatened by the flooding to find a place to stay with friends or relatives, or to seek out one of several shelters.

The towns of Edenville, Sanford and parts of Midland have been evacuated, Tisdale, the Midland spokeswoman, said.

The Weather Service issued flood warnings because 4 to 7 inches (10.2 to 17.8 centimeters) of rain has fallen since Sunday. Heavy runoff pushed rivers higher. This coming Saturday, there's a 30% chance of rain, with more moving into the area Sunday and Monday.

“Our hope is we get a little time for the water to recede," Tisdale said.

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This story has been corrected to show Selina Tisdale is the spokeswoman for the city of Midland, not Midland County.

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Associated Press environmental writer John Flesher contributed from Traverse City, Michigan. Webber reported from Oak Park, Illinois, and Williams from West Bloomfield, Michigan.

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