(CNN) Houston's mayor Saturday ordered nearly 300 people to leave their flooded homes, and another large city scrambled to restore water service as President Donald Trump visited flood victims and relief workers in Texas and Louisiana eight days after Hurricane Harvey struck.

In Houston, Mayor Sylvester Turner said people who had chosen to stay in inundated homes in the western part of the city must depart by 7 a.m. CT Sunday, after which the CenterPoint Energy utility will turn off power to those residences.

Turner said he's ordering the evacuation in part out of concern for the safety of firefighters, who would have trouble responding to emergencies in inundated areas.

President Donald Trump and first lady Melania Trump talk with people impacted by Hurricane Harvey in a Houston neighborhood on Saturday.

Public safety personnel will be in the area -- south of Interstate 10 and north of Briar Forest Drive -- to help people depart, he said.

Emergency workers scouted the area Friday to learn how many people had not left their flooded homes. Parts of western Houston have seen sustained flooding in part because the Army Corps of Engineers has intentionally released water from two swollen reservoirs -- and the flooding there won't recede soon, Turner said.

"I have to balance the interest of those who choose to stay" against the safety concerns for emergency personnel, Turner said.

The evacuations represent a tiny snapshot of the massive challenges presented by Harvey, a storm that left at least 50 dead, displaced tens of thousands of people and spurred disaster declarations in dozens of counties.

In Beaumont, a city of 118,000 east of Houston, officials said Saturday they were on the cusp of ending a three-day tap water outage that forced a hospital to evacuate its patients.

The city lost water pressure early Thursday when floodwaters disabled two pumps that send water to a treatment plant. By Saturday evening, workers had installed six temporary pumps, ready to again send water to the plant.

Service will resume soon, once the system is cleaned of mud and debris, but even when it does, people should boil the water they intend to consume until further notice, the city said.

"Be patient with us. We'll continue to work around the clock, night and day, and restore this city," City Manager Kyle Hayes said.

Photos: Hurricane Harvey slams Texas Downtown Houston is seen behind the flooded Buffalo Bayou a few days after Hurricane Harvey came ashore in August 2017. The Category 4 storm caused historic flooding. It set a record for the most rainfall from a tropical cyclone in the continental United States, with 51 inches of rain recorded in areas of Texas. An estimated 27 trillion gallons of water fell over Texas and Louisiana during a six-day period. Hide Caption 1 of 22 Photos: Hurricane Harvey slams Texas NASA astronaut Jack Fischer photographed Hurricane Harvey from the International Space Station. Hide Caption 2 of 22 Photos: Hurricane Harvey slams Texas Steve Culver comforts his dog Otis in the hurricane aftermath. Harvey destroyed most of his home in Rockport while he and his wife were there. Hide Caption 3 of 22 Photos: Hurricane Harvey slams Texas Houston police officer Daryl Hudeck carries Catherine Pham and her 13-month-old son, Aiden, after rescuing them from floodwaters. Hide Caption 4 of 22 Photos: Hurricane Harvey slams Texas A damaged home is seen in the Key Allegro neighborhood of Rockport. Hide Caption 5 of 22 Photos: Hurricane Harvey slams Texas A car is submerged by floodwaters on a freeway near downtown Houston. Hide Caption 6 of 22 Photos: Hurricane Harvey slams Texas Melani Zurawski cries while inspecting her home in Port Aransas, Texas. Hide Caption 7 of 22 Photos: Hurricane Harvey slams Texas A graveyard is flooded in Pearland, Texas. Hide Caption 8 of 22 Photos: Hurricane Harvey slams Texas Soldiers with the National Guard patrol Rockport, looking for residents trapped in their homes. Hide Caption 9 of 22 Photos: Hurricane Harvey slams Texas Evacuees are loaded onto a truck in Houston. Hide Caption 10 of 22 Photos: Hurricane Harvey slams Texas People push a stalled pickup through a flooded street in Houston. Hide Caption 11 of 22 Photos: Hurricane Harvey slams Texas Rockport residents return to their destroyed home. Hide Caption 12 of 22 Photos: Hurricane Harvey slams Texas Rescue boats fill Tidwell Road in Houston as they help flood victims evacuate the area. Hide Caption 13 of 22 Photos: Hurricane Harvey slams Texas People wait to be rescued from their flooded home in Houston. Hide Caption 14 of 22 Photos: Hurricane Harvey slams Texas Volunteers in Dallas organize items donated for hurricane victims. Hide Caption 15 of 22 Photos: Hurricane Harvey slams Texas When Harvey slammed the Texas coast and flooded much of Houston, volunteers sprang into action. Some came from as far away as the Florida Everglades, boats in tow, ready to rescue people trapped in their homes. Hide Caption 16 of 22 Photos: Hurricane Harvey slams Texas Larry Koser Jr. and his son Matthew look for important papers and heirlooms inside a flooded home in Houston. Hide Caption 17 of 22 Photos: Hurricane Harvey slams Texas Members of the National Guard rest at a furniture store in Richmond, Texas. Hide Caption 18 of 22 Photos: Hurricane Harvey slams Texas Volunteer rescue workers help a woman from her flooded home in Port Arthur, Texas. Hide Caption 19 of 22 Photos: Hurricane Harvey slams Texas This aerial photo shows flooded residential neighborhoods in Houston. Hide Caption 20 of 22 Photos: Hurricane Harvey slams Texas Tammy Dominguez and her husband, Christopher, sleep on cots at the George R. Brown Convention Center, where thousands of people were taking shelter in Houston. Hide Caption 21 of 22 Photos: Hurricane Harvey slams Texas An elderly patient waits to be rescued from the Gulf Health Care Center in Port Arthur. The facility was evacuated with the help of first responders and volunteers. Hide Caption 22 of 22

The tap water outage, which prompted city officials to begin distributing bottled water to residents Friday, was just one headache for a community struggling with a severely flooded Neches River.

The river began receding Friday evening but still was about 16 feet above flood stage and 7 feet above record level late Saturday morning.

Trump's second visit to region

Speaking briefly with reporters as he toured a Harvey relief center in Houston's NRG stadium, Trump said, "Really, I think people appreciate what's been done. It's been done really efficiently, really well and that's what we want. I'm very happy with the way it's been going."

He continued, "As tough as this was, it's been a wonderful thing, I think, even for the country to watch, even for the world to watch. It's been beautiful. Have a good time everybody, I'm going to be doing a little bit of help over here."

Trump then went to Lake Charles, Louisiana, where he met with Louisiana politicians as well as members of the National Guard and Cajun Navy , a grass-roots group that came together after Hurricane Katrina and has helped Texans in Harvey's aftermath.

"It was an honor to meet him," said Ben Husser, a Cajun Navy member. "I'm glad to know that he cares enough to come down here and spend time with the people in this area that were devastated and were affected by this storm. It means a lot."

JUST WATCHED Family and pet pig saved from flood waters Replay More Videos ... MUST WATCH Family and pet pig saved from flood waters 03:21

Trump is trying to reassure those in need that federal resources will be there as they begin rebuilding. The administration on Friday asked Congress for $7.85 billion in disaster relief funding as part of an initial request for funds.

Turner, Houston's mayor, said he asked Trump for $100 million to help with debris removal. The President, Turner said, indicated that the vast majority, if not the entire request, will be granted.

Texas' governor has said that more than 440,000 people have registered for emergency assistance from the Federal Emergency Management Agency, which has approved $79 million to help victims of the storm.

After Hurricanes Katrina and Rita hit the Gulf Coast in 2005, $5.8 billion in individual assistance money was given to nearly 916,000 people affected by those storms.

As the government works to help those affected by Harvey, Hurricane Irma is looming in the Atlantic as a threat to Caribbean islands -- and potentially, by next week, to the United States.

Death toll hits 50

Other statistics only begin to hint at the scope of the punishing deluge and what the months of recovery will entail:

About 27 trillion gallons of rain fell on Texas and Louisiana over six days.

More than 72,000 people have been rescued.

About 10% of the structures in Harris County were flooded, the county says.

While water is receding in many areas, it still was waist-deep Saturday in western Houston's Barker Cypress area. Ryan Short, who along with this family left their apartment ahead of Harvey, returned on a small boat to pick up a few possessions -- including something special for his 2-year-old son, Jacob.

Short re-entered the apartment to find all kinds of belongings floating in knee-high water. Eventually, he found the main thing he was looking for: his son's small bicycle, which he hopes will help the boy cope with being displaced.

"He's got to have his bike," Short said. "He's not having anything to connect with -- it's hard."

Lee Dufrene, of Austin, paddled Short to the apartment. The two connected after Dufrene drove his boat from Austin to help Harvey victims. He said he knows what it's like to be flooded out of a home.

"I was in the flood of Onion Creek in Austin 2013, and I just wanted to come help," he said.

Major damage at schools

The Houston Independent School District is scrambling to recover from the storm.

Harvey and its aftermath caused so much damage that 10,000 to 12,000 students -- out of the district's 218,000 pupils -- will have to move temporarily to new schools, the district said Saturday in a series of tweets.

The hurricane prevented the schools from starting their years as planned on August 28. Superintendent Richard Carranza told CNN's "New Day" on Friday that he intends to have classes start September 11.

But it's possible the opening will have to come later to avoid putting children "in harm's way," the district said Saturday via Twitter.

We're working hard to get schools restored. It's going to take money, manpower, & we ask Houston 4 patience, Board pres @Wandaful1913 says — Houston ISD (@HoustonISD) September 2, 2017

Many of its schools suffered major damage. The district has looked at 245 of its schools so far, and of those, 115 will be deep-cleaned and ready for classes to start September 11, the district's Chief Operating Officer Brian Busby said.

Chemical plant fire

Fires broke out over two days at a chemical plant near Houston that was flooded by Harvey, and authorities said they expect more flames there. Three containers burned since Thursday at the Arkema site in Crosby after Harvey's floodwaters knocked out equipment used to keep the plant's volatile chemicals cool, Harris County Assistant Fire Chief Bob Royall said.

Officials decided to let the remaining six containers catch fire and burn out rather than endanger firefighters, the US Environmental Protection Agency and Texas Commission on Environmental Quality said in a joint statement.