Rescuers are rushing to evacuate people stranded by floodwaters across the southern Brazilian state of Rio Grande do Sul, where at least 90 people have been killed and more than 130 others are missing.
The state capital of Porto Alegre has been virtually cut off by the flooding, with the airport and bus station closed and main roads blocked.
Reporting from the city on Tuesday afternoon, Al Jazeera’s Latin America editor Lucia Newman said the situation had become “very desperate” as volunteers and rescue crews try to evacuate residents.
“Everywhere you look, people have no water, no electricity. Sewage has, in this part of town which is downtown, completely come up.”
The state’s Civil Defence agency said the death toll has risen to 90 with another four deaths being investigated. Another 131 people are still unaccounted for, and 155,000 are homeless.
Heavy rains that began last week have caused rivers to flood, inundating whole towns and destroying roads and bridges.
In Porto Alegre, a city of 1.3 million residents on the Guaiba River, residents faced empty supermarket shelves and closed gas stations, with shops rationing sales of mineral water.
Five of Porto Alegre’s six water treatment facilities are not working, and Mayor Sebastiao Melo on Monday decreed that water be used exclusively for “essential consumption”.
“We are living an unprecedented natural disaster, and everyone needs to help,” Melo told reporters.
“I am getting water trucks to football fields, and people will have to go there to get their water in bottles. I cannot get them to go home to home.”
Almost half a million people were without power in Porto Alegre and outlying towns, as electricity companies cut off supplies for security reasons in flooded neighbourhoods.
The national electrical grid operator ONS said five hydroelectric dams and transmission lines were shut down due to the heavy rains.
Al Jazeera’s Newman reported that in nearby Eldorado do Sul, a city of 50,000 residents just across the river from Porto Alegre, the streets were “completely covered” with floodwaters on Tuesday.
“It was a desolate situation and desperate for the people who are being rescued, one by one,” said Newman. She explained that large vessels can’t get into the city, which has forced rescuers to use smaller boats.
“It could take days and weeks more before everyone is safe,” she explained.
The downpour has stopped for now, but a looming cold front is expected to bring more severe rain starting on Tuesday night, mainly in the southern part of the state, according to Brazil’s National Meteorological Institute.
The rainfall could exceed 150 millimetres (nearly six inches) by early Wednesday.
Back in Porto Alegre, resident Maria Vitoria Jorge told The Associated Press that she decided to leave behind her flooded apartment building downtown.
She withdrew about 8,000 reais ($1,600) from her savings to rent an apartment for herself and her parents elsewhere in the state.
“I can’t shower at home, wash the dishes or even have drinkable water,” the 35-year-old yoga teacher told the news agency from her car as she prepared to depart her old home.
She had about four litres (one gallon) of water for the 200km (125-mile) drive to the city of Torres, which has so far been unaffected by the floods.
Another resident, Adriano Hueck, on Tuesday was attempting to retrieve medicine stocked at a friend’s warehouse, which is partially flooded.
“If we can save some of it, there’s still a chance it can be useful in hospitals,” said the 53-year-old, who then pointed towards another part of the city. “My house is somewhere there. You can’t even see its roof now.”
