Five days after Hurricane Ida lashed the Southeast and with more than 800,000 homes and businesses still without power, the hunt for life’s essentials — groceries, cleaning supplies and fuel — was fueling dread of the challenges still ahead.

Lines stretched for blocks Friday at gas stations in Louisiana. Some supermarkets had begun rationing water, ice, bread, milk and other staples, while one pharmacy chain had deployed mobile units to devastated communities. Aid workers have been filing into darkened neighborhoods at night to serve food by the taillights of their trucks.

Residents with generator power or a place to stay outside the hardest-hit regions have peppered social media with offers of help for shut-in neighbors. One Louisianian ran groceries and ice from a supermarket in Lafayette to an elderly Catholic nun in New Orleans, some 2½ hours away in ideal conditions.

The fuel shortages have made other essential resources more scarce as families stock up to avoid multiple shopping trips and wasting critical supplies. The result, residents and aid workers say, is a growing sense of anguish as Louisianians confront the storm’s sprawling aftereffects.

“I’m passionate about making sure people know about how impactful the storm really was, even though you don’t see video of the French Quarter being destroyed,” said Blair Broussard, who left her home in New Orleans’s Uptown neighborhood to be with her mother in Lafayette and later delivered groceries to the nun. “It’s life-altering. Folks can’t get the things they need. They can’t talk to their doctors. Kids won’t be going to school next week.”

The Southeast’s supply chains have largely withstood the worst of the Category 4 storm, which made landfall Sunday with 150 mph winds and blanketed the region in darkness. Grocery-chain officials say they are receiving shipments and replenishing shelves, and oil pipelines that rerouted fuel in preparation for Ida restarted operations soon after it passed.

Waffle House, considered by emergency management officials to be the gold standard of disaster preparedness, reopened all but 10 of the 90 restaurants it closed as the hurricane struck, a spokeswoman told The Washington Post.

But the prolonged power outages — Ida wreaked unprecedented havoc on Louisiana’s electric grid — amid the hot and muggy summer quickly became Ida’s most worrisome fallout, say residents and aid workers on the Gulf Coast.

An estimated 825,000 electric meters remained offline as of Friday, including 700,000 from Entergy, Louisiana’s largest utility. The company said it would be another five days before its grid was fully restored, down from earlier estimates of up to three weeks.

Tracking service GasBuddy reported more than 7 in 10 fuel stations in Baton Rouge did not have gasoline Friday morning, nor did 66 percent of stations in New Orleans. Half of locations in Lafayette, which was largely unaffected by the storm, also were out of fuel. Residents of harder-hit areas have been driving there to fill up.

Shoppers have packed Rouses Market locations. They have been snapping up water, ice, deli meats, bread, milk, diapers and cleaning supplies, said Tim Acosta, marketing director for Rouses, the region’s largest grocery chain. For high-demand items, some locations are limiting purchases to two per family.

All 66 Rouses stores in the region were open, powered by gargantuan generators installed years ago to avoid outages after hurricanes, Acosta said.

“This is not our first storm,” he said.

But many Rouses locations are operating on reduced hours — from 7 a.m. to 5 p.m. instead of 10 p.m. — because of limited worker availability. Many Rouses associates sustained damage to their homes or need to spend time caring for family, Acosta said.

For the rest of the company’s employees, it’s all hands on deck: Acosta was unloading bags of ice from a refrigerated truck at a store in Thibodaux during a phone interview. On a subsequent call, he was directing delivery trucks entering the store’s parking lot.

“We have product coming into our stores,” he said. “We’re finding ways to make it happen.”

“Over here!” he shouted a moment later to a truck driver, the sound of the vehicle’s engine audible over the phone in the background.

Winn-Dixie, the region’s other major grocery chain, said on its website that all but one location in the region was open Friday, though some had reduced hours. By Saturday, the company said, those stores would be open at normal times. A representative did not respond to a request for comment.

CVS Pharmacy spokeswoman Amy Thibault said in an email that 50 of its 134 locations in Louisiana and Mississippi were closed because of power loss or physical damage. She said the company was rerouting phone systems from closed pharmacies to nearby open locations.

Walgreens deployed three mobile pharmacies between Houma and Larose, two communities southwest of New Orleans that sustained major damage, spokeswoman Erin Loverher said.

While some bank branches in New Orleans were closed because of the power outages, some ATMs were still in service. Liberty Bank, which serves several states including Louisiana and Alabama, said in an alert on its website that two ATMs were in service in the city but that all its New Orleans branches remain closed.

Through its Critical Needs Assistance program, the Federal Emergency Management Agency is providing one-time payments of up to $500 for residents of parishes that were included in the federal disaster declaration. While FEMA is helping coordinate efforts to deliver fuel and restore power to areas disrupted by the storm, the agency is not playing a direct role in getting residents cash, according to acting press secretary Caitlin Justesen.

Even with stores open, residents are still often unable to access some basic supplies, especially in outlying communities. With public transportation largely shuttered around New Orleans, the scarcity of gasoline presents a difficult choice, aid workers say: Risk using precious fuel to drive unpredictable streets to grocery stores or sit in gas lines, or wait at home for food distribution that may not arrive.

“We’ve got folks who can’t come pick up food from us anymore because they don’t have gas in their car,” said Nate Mook, chief executive of the World Central Kitchen relief agency. “All of these things combine — the lack of fuel, the lack of power and electricity. It’s a challenge, and it’s adding up.”

World Central Kitchen set up its own fuel depot, Mook said, with gasoline brought in from out of state to fill up its vehicles. The city government’s vehicle fleet does not have enough gasoline, so relief agencies have largely taken up the responsibility of making deliveries to neighborhoods still shut in by closed roads or downed power lines.

After distributing dinner in parts of New Orleans, aid workers venture out in SUVs into isolated communities without power to hand-deliver meals and other essentials.

Aid workers are strategizing, Mook said, over what kinds of food to distribute in addition to hot meals and sandwiches. Raw meat can be given out only sparingly; neighborhood barbecues have become a popular way of feeding a whole block of non-shelf-stable protein, while helping cooks avoid preparing meals in already hot kitchens.

Fresh fruit — World Central Kitchen founder and celebrity chef José Andrés purchased nearly half a million bananas, oranges and grapefruits from local farmers and suppliers — is nutrient-dense and does not have to be refrigerated. It also makes for a good breakfast in place of cereal and milk or eggs, Mook said.

“Even if grocery stores open, that’s not helpful if you don’t have power and you can’t put things in your refrigerator,” he said. “A box of groceries is not going to be helpful when they can’t keep anything cold or they can’t cook anything.”

Hamza Shaban contributed to this report.