PORT ARTHUR, Texas (Reuters) - A flood-hit southeast Texas city lost its drinking water supply and police and soldiers rescued thousands still stranded on Thursday after powerful storm Harvey killed 44 people and displaced more than a million on the Gulf Coast.

Some 779,000 Texans have been told to leave their homes and another 980,000 fled voluntarily amid dangers of new flooding from swollen rivers and reservoirs, according to Department of Homeland Security acting secretary Elaine Duke. 

The city of Beaumont, about 80 miles (130 km) east of Houston, had its water supplies cut off and was threatened by a rising river that forced the evacuation of its hospital and residents in neighboring Orange County.

There were explosions at a chemical plant about 25 miles (40 km) east of Houston after it was engulfed by floodwater.

The loss of water and health risks from flooding were among hazards emerging in the aftermath of Harvey, which roared ashore late last Friday as the most powerful hurricane to hit Texas in half a century. It has since been downgraded to a tropical depression as it heads inland, leaving devastation across more than 300 miles (480 km) in the southeast corner of the state.Jessica Richard, 24, said she waited out the storm in her home in Port Arthur, about 85 miles (135 km) east of Houston, until Thursday morning when water on her street rose to waist-high. She was picked up by a passing truck.

Richard said her nephew had been trapped with several family members overnight in a flooded apartment. “He said there were snakes in the water and spiders crawling up the walls. But they got out,” she said.

At least 44 people were dead or feared dead in six counties including and around Houston, officials said. Another 19 remained missing.

HOUSE-BY-HOUSE SEARCH

In the U.S. energy hub of Houston, firefighters conducted a house-by-house search to rescue stranded survivors and recover bodies as some residents began to return to their homes to assess the damage.