Electric company workers started going door-to-door Sunday in a still-flooded area of west Houston under a mandatory evacuation order, warning that service would be shut off nine days after Tropical Storm Harvey ravaged the city.

Crews with Center Point Energy checked homes in the zone that Mayor Sylvester Turner ordered evacuated where about 300 residents still remain. People in houses that have taken no water will not have their electricity cut off.

Water releases from the Addicks and Barker reservoirs need to flush through the area after several feet of rain from Harvey filled them to capacity.

“If you have water in your homes, I have issued a mandatory evacuation for them because it’s dangerous for those who are choosing to live there,” Mayor Sylvester Turner told NBC’s Meet the Press.

“But also, it’s very, very dangerous for our public responders, first responders, who are needing to be out there, trying to provide protection to them,” he added.

Trump, during his visit, mingled with evacuees at emergency shelters and handed out hot dogs at the NRG Center.

In Beaumont, Texas, water service was partially restored Sunday morning, three days after floodwaters inundated the water treatment plant left the city's 118,000 residents without drinking water.

Most residents found their water pressure was quite low, however, and the water still must be boiled before it can be consumed. When people heard that the National Guard was distributing cases of water at a parking lot north of downtown, the news attracted a line of cars a mile long.

Wilbert Johnson sat in line for 30 minutes in his black pickup. He said he missed Saturday's water distribution because he had to cook meals for his wife, who has cancer. So when he heard it was happening again Sunday, he made sure to get there early.

"You don't think about water too much until you run out of it," said Johnson, 69, of Beaumont. "But when you're using bottled water to cook, brush your teeth and clean your dishes, you go through it pretty quick."

Earlier in the day, Johnson drove his truck to the still-flooded Neches River and dipped a garbage bucket into the water. He brought that home and used the water to flush his toilets.

"In times like this you just have to live country," Johnson said.

Dozens of people were still cut off from their homes near the town of Liberty because of the swollen Trinity River.

Maggie King, who lives in the city of about 8,400 people 45 miles northeast of Houston, was on hand with her two children to greet a Texas National Guard helicopter that landed at the fire department Sunday with pallets of drinking water.

She said recovery from the storm is far from over because so much needs to be repaired.

In Port Arthur, school superintendent Mark Porterie said the district “is looking at about three weeks before the school year begins, if not sooner,” he told the Enterprise. Some schools still had several inches of standing water inside — while a middle school was still being used a Red Cross shelter.

In Crosby, authorities on Sunday set a controlled explosion at the Arkema plant where trailers with hazardous materials had ignited in recent days because of lack of power and refrigeration.

In a statement, Harris County Fire Marshal M.S. Montgomery said firefighters ignited the remaining trailers at the Arkema plant in a "proactive" attempt to control the effects of the power outage. Montgomery said a 1.5-mile evacuation radius remained in place.

In Bellaire, in southwest Houston, residents complained that scavengers have descended to pick through flood-damaged items piled in front of their homes. Police Chief Byron Holloway is asking residents drying items they hope to salvage not to place them by debris intended for trash and put them instead closer to their homes.

The death toll tied to the storm is at least 44 and pushed the Harris County morgue to near capacity. Financial estimates of the damages have soared well above $100 billion.

Contributing: Christopher Maag, The (Bergen, N.J) Record in Beaumont; The Associated Press