How 2,000-year-old Roman dam stored Spanish metropolis secure from floods whereas trendy defences failed as public anger grows at authorities over catastrophe which will have killed 400

While horrifying images have laid bare the catastrophic effects of flooding across Spain over recent days, an incredible video has also emerged showing how ancient technology helped to save a small town from destruction.

A 2,000-year-old Roman dam in Aragon prevented flooding in Almonacid de la Cuba, with footage showing the torrent of water avoiding buildings by just metres as it was directed downhill.

As heavy rains lashed the area, water was stored up to the limit of the dam before cascading down the side, avoiding an overflow into the town, Spanish media reports.

It meant residents were protected from the flooding seen elsewhere in Spain, with no damage or injuries reported in the town.

Tragically, the floods have been deadly elsewhere, with reports suggesting that more than 400 people may have lost their lives in the disaster as official figures indicate that 2,000 people remain missing.

A 2,000-year-old Roman dam in Aragon helped to prevent flooding in a nearby town

Incredible footage shows a torrent of water avoiding buildings by just metres as it was directed downhill

Cars piled up in a ditch at a construction site after being swept off the road by powerful floods

Civil Guard officers search for survivors inside cars trapped under the foundations of a building under construction in the town of Paiporta, Valencia

A bulldozer is used to clear vehicles from streets in the town of Catarroja, in the region of Valencia

Volunteers and residents cleanup the mud four days after flash floods swept away everything in their path in Paiporta

The storm and flooding has left carnage in its wake, with a huge clean-up operation now underway

Vehicles pile up in the streets caused by late Tuesday and early Wednesday storm that left hundreds dead or missing in Alfafar, Valencia

Residents wade through a mud-covered street after flash floods in Paiporta, province of Valencia, eastern Spain

Thousands of people arrive at the Ciudad de las Artes y las Ciencias complex to volunteer in helping in the reconstruction and cleaning of towns affected by flash floods, in Valencia

Volunteers armed with brooms prepare to help with the mammoth clean-up operation 

Food donations were made available to hard-hit residents in Valencia

Some motorists attempted to drive through the floodwaters in Majorca, while others abandoned their vehicles as torrents of water poured through the street

The official death toll stands at 211, Spanish Prime Minister Pedro Sanchez told a press conference on Saturday morning, as rescue workers continue to comb seemingly abandoned homes as they search for survivors or bodies.

‘There are still dozens of people looking for their loved ones and hundreds of households mourning the loss of a relative, a friend or a neighbour,’ Sanchez said four days after floodwaters swept over Valencia. 

As criticism of the local and central government response mounts, Sanchez said: ‘The situation we’re experiencing is tragic and dramatic. We’re almost certainly talking about the worst flood our continent has seen so far this century. 

‘I’m aware that the response we’re mounting isn’t enough. I know that. And I know there are severe problems and shortages and that there are still collapsed services and towns buried by the mud where people are desperately looking for their relatives, and people who can’t get into their homes, and houses that have been buried or destroyed by mud. I know we have to do better and give it our all.’ 

Valencia’s regional president Carlos Mazón said the government’s emergency line was still receiving thousands of calls from people desperately searching for relatives and friends, days after the first warnings were put out.

Many Valencia residents have said alerts – issued at 8pm on Tuesday – came too late, with many stuck in traffic on the way back from work trapped in their vehicles or clambering onto their car roofs as waters rose.

Incredibly, a woman was rescued alive yesterday after three days inside a car beside her dead sister-in-law.

Aid workers are said to have discovered her after hearing her cries for help as they checked vehicles in the stricken town of Benetusser.

Regional Civil Protection president Martin Perez revealed the miracle survival late last night to applause from 400 volunteers in a municipal sports hall in nearby Moncada.

Civil protection officers search cars for survivors in Benetusser, where a woman was found alive in car wreckage yesterday

Mangled cars which were swept on to each other by the powerful floodwaters are inspected by civil protection officers in Benetusser

Streets across Valencia have been filled with cars which were lifted up by the floodwaters on Tuesday night

Regional Civil Protection president Martin Perez revealed the miracle survival late last night to applause from 400 volunteers

He looked visibly moved as he told them, wearing his mud-covered uniform after his life-saving work assisting the victims of one of Europe’s worst-ever natural disasters: ‘After three days we’ve found a person alive in a car.’

Mr Perez had to cut short his address with the mix of emotion and the applause from the volunteer workers listening to him.

The unnamed woman is understood to have been rescued from a flooded tunnel in Benetusser on the outskirts of the provincial capital in an area called Horta Sud, where most of the 211 victims of the flooding known to have died so far, occurred after torrential rain on Tuesday.

Firefighters in protective clothing were filmed up to their necks in water yesterday checking the mangled wreckage of vehicles in the tunnel three days after the killer flash floods caused by storm downpours,

Local reports said she had been trapped by other cars piled on top of hers. One said she had been forced to spend three days beside her dead sister-in-law while she waited for help to arrive.

The tunnel, which lies between the municipalities of Benetusser and Alfafar has been branded the ‘black tunnel’ by leading Spanish daily El Mundo.

Firefighters have been working with a volunteer tractor driver to pull cars out of the water before they are checked for occupants.

They are understood to be working with the theory that the drivers of vehicles further into the tunnel are likely to have been already inside it when they were stopped in their tracks by flash floods – and others in front of them were swept into the tunnel from other areas after their occupants managed to escape.

Earlier today it was confirmed Civil Guard divers are now entering flooded garages in Benetusser where locals have told them there are still people trapped in what is expected to be a grim search for bodies rather than survivors.

The storms concentrated over the Magro and Turia river basins and, in the Poyo riverbed, produced walls of water that overflowed riverbanks, catching people unaware as they went on with their daily lives.

In the blink of an eye, the muddy water covered roads, railways and entered houses and businesses in villages on the southern outskirts of Valencia city.

Flood defences in the region were not strong enough to handle such extreme weather while drainage systems were inadequate, locals and witnesses have said.

That is despite the coastal region being particularly at risk of flash flooding due to its hard ground and susceptibility to the DANA weather system as its called in Spain.

Unlike common storms, it can form independently of polar or subtropical jet streams, and happens when cold air blows over warm Mediterranean waters causing hotter air to rise quickly and form towering, dense, water-laden clouds.

Cars are piled high on a mud-sodden street in Valencia after the region was hit by deadly floods

People wearing PPE try to sweep away mud as they desperately clean up the streets

A view of the demolition works at a damaged house after flash floods in Letur, province of Albacete, Spain

A woman carries a shopping trolley through a flooded street in Manasa, province of Valencia

A volunteer cleans up a town square after flash floods in Paiporta, a town which was particularly affected by the floods

A sign reading ‘medical team’ is placed inside an high school that was set up to provide medical assistance and essential goods

These can remain over the same area for many hours, raising their destructive potential, often resulting in large hail storms and tornadoes, as seen this week.

The country has also suffered through an almost two-year drought, meaning that when the deluge happened, the ground was so hard that it could not absorb the rain, worsening the effect of the flash floods.

And then there is the unusually high temperature of the Mediterranean Sea. It had its warmest surface temperature on record in mid-August, at 28.47 degrees Celsius (83.25 degrees Fahrenheit), said Carola Koenig of the Centre for Flood Risk and Resilience at Brunel University of London.

Experts say that drought and flood cycles are increasing with climate change.

Volunteers queue to get guidelines on how to get organised to best provide help to those affected by the floods and heavy rain

As well as Valencia, the floods have affected Castilla-La Mancha, the Region of Murcia and Andalusia, as well as the Balearic islands.

In Majorca, holidaymakers and locals were told to stay inside on Friday as storms battered coastal areas and submerged roads.

Dramatic footage showed motorists driving through high floodwaters and huge torrents of water hurtling through towns.

One tourist shared a video of terrifying lightning above her villa, writing on Friday night that the storm has ‘brought heavy rainfall and violent thunderstorms’.

She said the weather system had left some roads impassable and ‘parts of the island no longer accessible’ with reports of drivers being rescued from their cars in the popular coastal resort of Santa Ponca.

Meanwhile a Brit who lives part-time in Majorca told MailOnline he did not leave his apartment on Friday due to ‘heavy rain and thunder all day’, adding that he could see a ‘continuous water spout’ from his patio.

A passer-by walks across the street during a downpour in Palma on November 1 

Water streams down a stairs in a town in Majorca as the roads are submerged by high floodwaters

Torrents of water hurtled through towns on Majorca this week amid heavy rains

Thunder and lightning was seen across the island on Friday, with many people staying indoors

Photo shows a tornado waterspout that injured two in Spain 

The extreme conditions are expected to ease today, with emergency services saying that the worst of the storm seems to have passed, but the public warned to stay alert as heavy rains continue in many areas.

‘The great luck is that people stayed at home, otherwise we could be facing another scenario,’ one emergency services chief told local media.

Tragically, it was a very different situation in Valencia this week, where warnings came too late and many people were caught out by flash flooding.

The floods amount to the deadliest natural tragedy in living memory in Spain, and if the death toll continues to rise, could be Europe’s worst storm disaster in more than 50 years.

The Spanish government has sent thousands of troops to assist Valencian officials in what marks the biggest peacetime deployment of troops in the country’s history.

Spanish Prime Minister Pedro Sanchez delivering an institutional declaration on the situation after flash floods in the province of Valencia and neighbouring regions

But many of those affected by the floods say they have felt abandoned by the authorities.

In Valencia’s Picanya suburb, shop-owner Emilia, 74, told Reuters on Saturday: ‘We feel abandoned, there are many people who need help. It is not only my house, is all the houses and we are throwing away furniture, we are throwing away everything.

‘When is the help going to come to have fridges and washing machines? Because we can’t even wash our clothes and we can’t even have a shower.’

Nurse Maria Jose Gilabert, 52, who also lives in Picanya, said: ‘We are devastated because there is not much light to be seen here at the moment, not because they are not coming to help, they are coming from all over Spain, but because it will be a long time before this becomes a habitable area again.’

Thousands have taken matters into their own hands, with pictures showing stoic volunteers taking to the streets to help in the mammoth clean up operation.

Areas on the main promenade of Palma are cordoned off to avoid dangers from rain or wind

Carrying brooms, shovels, water and basic foods, hundreds of people have walked miles each day to deliver supplies and help clean up the worst-affected areas.

Spain’s Mediterranean coast is used to autumn storms that can cause flooding, but this episode was the most powerful flash flood event in recent memory.

Older people in Paiporta, ground zero of the tragedy, claim that Tuesday’s floods were three times as bad as those of 1957, which caused at least 81 deaths and were the worst in the history of the tourist eastern region. 

That episode led to the diversion of the Turia watercourse, which meant that a large part of the city was spared of these floods.

Valencia suffered two other major DANAs in the 1980s, one in 1982, with around 30 deaths, and another one five years later, which broke rainfall records.

This week’s flash floods are also Spain’s deadliest natural tragedy in living memory, surpassing the flood that swept away a campsite along the Gallego river in Biescas, in the northeast, killing 87 people in August 1996.