The hurricane has claimed over 44 lives already and continues to unleash its terror along the Gulf Coast, with people being told to leave homes amid dangers of new flooding from swollen rivers.
Nearly 44 have been killed till now.
Another 19 remain missing.
Some 779,000 Texans have been told to leave their homes.
A Texas city lost its drinking water supply and soldiers and police rescued thousands still stranded on Thursday as storm Harvey inflicted more suffering on the Gulf coast after killing 44 people and displacing over a million.
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, 80 miles (129 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) southeast 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 Friday as the most powerful hurricane to hit Texas in a half-century. It has since been downgraded to a tropical depression as it heads inland, leaving devastation across the southeast corner of the state.
Jessica Richard, 24, said she waited out the storm in her home in Port Arthur, about 85 miles (137 km) east of Houston, until Thursday morning when water on her street rose to waist-depth. She was picked up by a passing truck.
Richard said her nephew had been trapped overnight in a flooded apartment with several family members. "He said there were snakes in the water and spiders crawling up the walls. But they got out."
At least 38 people were dead or feared dead in six counties including and around Houston, local officials said. Another 19 remained missing.