Officials are starting to grapple with the costs of Harvey. Here's what you should know today.

In Harvey's Wake

The devastation was swift, and the recovery is far from over. Sign up for our ongoing coverage of Hurricane Harvey's aftermath. 

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Federal and state relief efforts are coming into focus as the extent of the damage wrought by Hurricane Harvey becomes apparent. But though floodwaters have ebbed, many parts of the state still face environmental hazards and other risks.

Houston Mayor Sylvester Turner on Saturday night called for a mandatory evacuation of flooded homes in parts of the city, saying water releases from the U.S. Army Corps of Engineers could leave "standing water in homes for two weeks." Turner said in messages posted to Twitter that the residents of 115 homes had already evacuated voluntarily, but that "people in about 300 inundated homes in the zone have so far chosen to stay despite [my] voluntary evacuation yesterday." The mandatory evacuation begins Sunday, and electricity to the flooded houses will be cut off starting at 7 a.m. 

Earlier Saturday, the Associated Press reported that many of Houston’s ultra-polluted Superfund sites are flooded, raising concerns about the spread of toxins.

Seven Superfund sites – a designation given to the country's most hazardous or contaminated places – in and around Houston were visited by the AP, who reported “all had been inundated with water, in some cases many feet deep.” Harris County, which includes Houston, has at least a dozen of these designated sites.

The EPA has determined 13 sites have been flooded or possibly damaged, the Texas Commission on Environmental Quality said in a news release Saturday afternoon. Of those, 11 are inaccessible to agency personnel, and two have been inspected and don't need emergency cleanup.

Houston officials also said several wastewater treatment plants in the city were flooded and asked residents to reduce their water usage until further notice. Officials said drinking water remained safe, though other parts of the county have been issued unsafe water notices. 

In Beaumont, part of an ExxonMobil refinery was flooding and oil from the facility had spilled onto a nearby road, the Beaumont Enterprise reported Saturday. A spokeswoman for the company told the Enterprise they were working to contain the spill and had alerted government authorities. 

The death toll for the storm has reached 50 people, the Houston Chronicle reported on Saturday, and the Texas Department of Public Safety said more than 185,000 homes have been damaged or destroyed by the storm, according to the Washington Post.

President Donald Trump visited the Houston area Saturday, where he met with Harvey survivors after being criticized for not doing so while in Corpus Christi and Austin on Tuesday. Saturday's visit marked the Houston mayor's first opportunity to talk to Trump since Harvey made landfall, and Turner said on Twitter that the meeting was "productive." 

"...told @POTUS of urgent need for $100 million to start debris removal speedily. He indicated 90-100% reimbursements to city," Turner posted on Twitter. "Asked @POTUS for expedited @fema application process for flood insurance claims from first responders. He gave a big thumbs up."

Trump on Friday called for $7.9 billion in federal assistance, a first installment in what’s expected to be a more expansive relief package, according to the Associated Press. Of that, $7.4 billion would go to the Federal Emergency Management Agency and $450 million to disaster loans for small businesses. The New York Times reported a second request for $6.7 billion would follow.

Abbott said Wednesday he expects the state will need far more than $120 billion, the amount of federal relief provided after Hurricane Katrina, the Post reported. And Turner told CNN Friday, “We need immediately, right now, just for debris removal alone, anywhere between $75 million to $100 million.”

In a message posted to Twitter, U.S. House Speaker Paul Ryan said the chamber will “act quickly” on disaster relief funding, with a vote expected to come next week when Congress returns from an August recess. Meanwhile, state lawmakers have set a committee hearing for Thursday to discuss housing needs in the wake of Harvey. Abbott has already said a second special legislative session would not be necessary, and that the state has enough resources to "address the needs between now and the next session."

Trump has said he plans to donate $1 million of his personal money to Harvey relief. He also has called for Sunday to be a national day of prayer for those impacted by the storm.

Abbott, Texas House Speaker Joe Straus, and Lt. Gov. Dan Patrick all said they would commit $100,000 through their campaigns to a Harvey relief fund announced by the governor Friday. Patrick added in a message posted to Twitter that he and his wife would make a personal donation of $25,000 to the fund – which Abbott wants to raise $100 million for over Labor Day weekend.

Meanwhile, schools in the state are facing delayed start dates as they deal with what could be, in some cases, months of necessary repairs. Houston Independent School District said in a message posted to Twitter it would be “months before school can open” and that they are “following strict guidelines in restoration.” Superintendent Richard Carranza told the Chronicle 10,000 to 12,000 students in the district could be sent temporarily to other campuses that were less damaged by the storm. The district also announced last week it would provide students with three free meals a day during the upcoming school year.

Officials at Spring Branch Independent School District also said Friday that classes would not start next week as expected, and that a new start date was still undecided. And Kingwood High School will remain shuttered for the entire school year, the principal told a local news station Saturday.

In total, more than 200 school districts have experienced delays due to the storm, according to a state estimate – including the indefinite closure of four smaller school districts along the coast.

Disclosure: ExxonMobil has been a corporate sponsor of The Texas Tribune. A complete list of Tribune donors and sponsors is available here.