Temperatures are rising in Texas after a record-breaking freeze wreaked havoc in the state, killing at least two dozen people and knocking out power for more than four million people at its peak. Aid continues to trickle into Texas as thousands remain in the dark and without water as of Sunday.

U.S. President Joe Biden approved a major disaster declaration for Texas on Saturday that makes federal funding available to people harmed by the storm, including assistance for temporary housing and home repairs and low-cost loans.

The governor of Texas announced it has brought in plumbers from out of state to help repair burst pipes. Homeowners or renters who do not have insurance may be able to seek reimbursement from the Federal Emergency Management Agency (FEMA).

The Texas National Guard and military members from several states were also helping to deliver and distribute bottled water to Texans in need.

Democratic Rep. Alexandria Ocasio-Cortez had raised $4.7 million in fundraising efforts to help Texans as of Sunday evening, according to her press secretary.

All power plants were back online this weekend and power had been restored to most homes as the weather returned to normal. The Texas Department of State and Health Services also announced that the vaccination process in the state has resumed. Texas will get nearly 600,000 first doses of the COVID-19 vaccine this week.

Houston announced Sunday afternoon it had lifted its boil-water notice effective immediately. However, concerns still remained about water supplies for millions of Texans.

Experts have warned that as more than 73 percent of the country's mainland was covered by snow last week, the melting water can trigger floods in the coming weeks.

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Blame game for skyrocketing energy bills

Water service remained disrupted for nearly a third of Texas residents Sunday evening according to CNN. More than 1,200 public water systems still reported disruptions in service. Some families are boiling snow on the ground in pots to get daily water supply.

Last week, a screenshot of a tweet spreading across social media shows one CenterPoint Energy customer in Texas was billed $202,102.16. The company providing electricity for greater Houston area clarified the billing was a mistake.

"We are aware of a recent technical issue caused by the power outage in Houston which led to the issuance of incorrect natural gas bill e-mails to some customers," the company tweeted on February 18. "If you have received an e-mail in the amount of $202,102.16, please disregard it. You do not owe this amount."

But more customers keep receiving large power bills over the past few days.

Some Texans who were still able to turn on lights or keep their fridge running found themselves with bills of $5,000 for just a five-day period, according to photos of invoices posted on social media by angry consumers.

Texas has a highly unusual deregulated energy market that lets consumers choose between scores of competing electricity providers. Some providers sell electricity at wholesale prices that rise in sync with demand, which skyrocketed when the state was gripped by extreme cold weather.

"The bill should go to the state of Texas," Houston Mayor Sylvester Turner said in an interview with CBS News on Sunday. "When they're getting these exorbitant electricity bills and they're having to pay for their homes, repair their homes, they should not have to bear the responsibility."

Texas Governor Greg Abbott said on Sunday that Texas utility regulators will temporarily ban power companies from billing customers or disconnecting them for non-payment after an emergency meeting with state lawmakers.

"Texans who have suffered through days of freezing cold without power should not be subjected to skyrocketing energy bills," Abbott told reporters on Sunday in San Antonio.

He said the Public Utility Commission of Texas will order electricity companies to pause sending bills to customers, and will issue a temporary moratorium on disconnection for non-payment.

The state will use the time to find a way to protect utility customers, Abbott said.

"The issue about utility bills and the skyrocketing prices that so many homeowners and renters are facing is the top priority for the Texas legislature right now," he said.

U.S. Senator Ted Cruz, who was forced to cut short a jaunt with his family to the Mexican beach resort of Cancun after public outrage, also distanced himself from the free-market system he had previously praised.

"This is wrong," Cruz wrote on Twitter. "No power company should get a windfall because of a natural disaster, and Texans shouldn't get hammered by ridiculous rate increases for last week's energy debacle. State and local regulators should act swiftly to prevent this injustice."

One environmental crisis triggers another

According to CNN, as the temperatures get warmer, unprepared homeowners, especially those in the south, could face the prospect of widespread damage and costly repairs.

According to the National Oceanic and Atmospheric Administration's Office of Water Prediction, more than 73 percent of the United States mainland was covered by snow last week. Soon, warmer temperatures will thaw that snow and ice, creating snowmelt runoff and increasing the risk for leaks and floods.

Meanwhile, the largest U.S. oil refiners have released tons of air pollutants into the skies over Texas this week, according to figures provided to the state.

Refiners and petrochemical plants along the U.S. Gulf Coast scrambled to shut production as an arctic air mass spread into a region unused to frigid temperatures. Shutdowns led to the refineries flaring, or burning and releasing gases, to prevent damage to their processing units. That flaring darkened the skies in eastern Texas with smoke visible for kilometers away.

"These emissions can dwarf the usual emissions of the refineries by orders of magnitude," said Jane Williams, chair of the Sierra Club's National Clean Air Team.

The 118,100 pounds of emissions from Motiva's Port Arthur, Texas, refinery between February 15 and 18 were more than three times the excess emissions that it declared to the U.S. Environmental Protection Agency for the whole of 2019.

Exxon Mobil said its Baytown Olefins Plant emitted nearly one ton of benzene and 68,000 tons of carbon monoxide, citing in its disclosure the halting of "multiple process units and safe utilization of the flare system."

Exxon blamed the shutdown of two Texas refineries on the freezing weather and loss of natural gas supplies. A spokesman said its petrochemical plants in Texas and Louisiana have supplied 560 megawatts to local communities, helping power about 300,000 homes.

(With input from agencies)