AUSTIN, Texas (CBSDFW/AP) – Power outages in Texas dropped below 1 million on Thursday morning for the first time in four days, but many people remain without electricity or safe drinking water after winter storms wreaked havoc on the state’s power grid and utilities.

This week’s extreme weather is blamed for the deaths of more than 30 people, some of whom perished while struggling to keep warm inside their homes. In the Houston area, one family succumbed to carbon monoxide from car exhaust in their garage. A grandmother and three children died when flames escaped the fireplace they were using to keep warm.

In Texas, more than 600,000 homes and businesses were still without electricity Thursday morning, down from about 3 million the day before. But Texas’ grid manager, under fire for its response to the winter storm, has warned that the outages could fluctuate during hours of peak energy demand.

Adding to the misery, the snowy weather has jeopardized drinking water systems throughout the state.

Texas officials ordered 7 million people – a quarter of the population of the nation’s second-largest state – to boil tap water before drinking it following days of record low temperatures that damaged infrastructure and froze pipes.

Water pressure has fallen across the state because lines have frozen, and many residents are leaving faucets dripping in hopes of preventing pipes from freezing, said Toby Baker, executive director of the Texas Commission on Environmental Quality.

Texas Gov. Greg Abbott urged residents to shut off water to their homes, if possible, to prevent more busted pipes and preserve pressure in municipal systems.

The governor said issues with natural gas and wind generators are continuing after days of efforts to restore power. He said around 19,800 MW of natural gas generation is still offline due to mechanical issues or lack of supply as of Wednesday afternoon.

Abbott said natural gas producers had been exporting it to areas outside of the state. He issued an order to help with power restoration efforts.

“I have issued an order, effective today, through February the 21st, requiring those producers that have been shipping to locations outside of Texas to, instead, sell that natural gas to Texas power generators, that will also increase the ability of gas-powered generators in Texas to increase power to the Texas power grid,” Abbott said.

The governor also said there was a conference call with President Joe Biden and other governors affected the winter storms in which the president said he would work with them on issues with spikes in natural gas prices.

The Electric Reliability Council of Texas (ERCOT) said Wednesday it does not have an exact timeframe for full power restoration. Earlier in the morning, officials said the best-case scenario would be rotating outages lasting 30 minutes to an hour later in the evening or early Thursday.

Abbott said the state would be investigating ERCOT and its response efforts due to the ongoing power outages.

“Today, I spoke with both the lieutenant governor and speaker and both the House and Senate will begin investigations next week. And that will begin a process where we fully evaluate exactly what was done and maybe not done in both the decision process as well as the action process by ERCOT,” Abbott said. “Making sure we get to the root of any mis-steps that took place, what was done and what could be done better.”

The state is also dealing with issues surrounding water and plumbing.

Abbott said the Texas Board of Plumbing Examiners is providing provisional licenses to out-of-state plumbers to help increase response to burst pipes and flooding. Plumbers with expired licenses in the state will be able to help as certain fees and examination requirements will be waived, according to Abbott.

The Texas Commission on Environmental Quality will also be looking into water quality issues. Many North Texas communities are under boil water notices.

“The State of Texas is working around the clock to provide the resources, assistance, and support that our communities need to respond to the impacts of this winter weather,” Abbott said. “We will continue to exhaust all available methods to restore power for Texans and ensure that our communities can recover.”