Why are floods in Libya so deadly?

CNN
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It started with a bang at 3 a.m. on Monday while Derna residents were sleeping. One dam burst, then another, Sending a huge wave of water It flowed through the mountains towards the Libyan coastal city, killing thousands while sweeping entire neighborhoods into the sea.

Doctors Without Borders said in a statement on Thursday that at least 5,000 people had died in Libya due to the floods it witnessed this week, in a review of previous estimates.

The population of the city of Derna in eastern Libya, the epicenter of the disaster, was about 100,000 people before the tragedy occurred. Authorities say at least 10,000 are still missing. CNN was unable to independently verify these numbers.

Buildings, homes and infrastructure were “destroyed” when a 7-meter wave hit the city, according to the International Committee of the Red Cross, which said on Thursday that bodies of the dead were now washing away again. shore.

But with thousands dead and many still missing, there are questions about why the storm that struck Greece and other countries caused more devastation in Libya.

Experts say that aside from the powerful storm itself, Libya disaster It has been greatly exacerbated by a deadly combination of factors including aging, deteriorating infrastructure, inadequate warnings and the effects of the accelerating climate crisis.

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The heavy rains that hit Libya on Sunday came through a system called Storm Daniel.

After the invasion of Greece, Turkey and Bulgaria Severe floods The cyclone killed more than 20 people and became a “medicinal storm” over the Mediterranean – a relatively rare type of storm with characteristics similar to hurricanes and tornadoes.

The medical ship’s strength strengthened as it crossed the unusually warm waters of the Mediterranean Sea before heavy rains fell on Libya on Sunday.

It brought more than 16 inches (414 mm) of rain in 24 hours to Al Bayda, a city west of Derna, a new record.

While it is too early to definitively attribute the storm to the climate crisis, scientists are confident that climate change is increasing the severity of extreme weather events such as storms. Warmer oceans provide fuel for storm growth, and a warmer atmosphere can hold more moisture, which means heavier rainfall.

Hannah Cloke, professor of hydrology at the University of Reading in the United Kingdom, said storms “are becoming more ferocious due to climate change.”

Derna is prone to flooding, and its dam reservoirs have caused at least five deadly floods since 1942, the last of which was in 2011, according to a recent report. Research paper Published by the Libyan Sebha University last year.

The two dams that exploded on Monday were built about half a century ago, between 1973 and 1977. By Yugoslav construction company. The Derna Dam has a height of 75 meters (246 feet) and a storage capacity of 18 million cubic meters (4.76 billion gallons). The second Al-Mansour Dam is 45 meters (148 feet) high and has a capacity of 1.5 million cubic meters (396 million gallons).

These dams have not been subject to maintenance since 2002, in the city Deputy Mayor Ahmed Madroud told Al Jazeera.

But the problems of the dams were well known. The Sebha University paper warned that dams in Derna have a “high potential for flood risk” and that regular maintenance is needed to avoid “catastrophic” floods.

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“The current situation in the Wadi Derna reservoir requires officials to take immediate action to conduct regular maintenance of existing dams,” the paper recommended last year. “Because if a major flood occurs, the result will be disastrous for the residents of the valley and the city.” It was also found that the surrounding area lacked proper vegetation that could prevent soil erosion. He called on residents of the area to be aware of the dangers of flooding.

Liz Stevens, professor of climate risk and resilience at the University of Reading in the UK, told CNN there are serious questions to be asked about the dam’s design standard and whether the risk of extremely heavy rainfall has been appropriately taken into account. account.

“It is very clear that had the dam not collapsed, we would not have seen this tragic number of deaths as a result,” she said.

“The levees would have initially held the water back, and their failure would likely have released all the water at once,” Stevens also told the Science Media Center, adding that “debris suspended in the floodwaters would have increased the destructive force.”

Derna has been bombed in the past and its infrastructure has deteriorated due to years of fighting.

Since the fight against ISIS and later against eastern commander Khalifa Haftar and his Libyan National Army, the city’s infrastructure has collapsed and become woefully inadequate in the face of floods such as those brought by Storm Daniel.

Petteri Taalas, head of the United Nations World Meteorological Organization, said better warnings could have avoided most of the casualties in Derna.

“If there had been a meteorological service functioning normally, the warnings would have been issued and the emergency department would also have been able to carry out evacuations of people and we would have avoided most of the casualties,” Taalas said. He told reporters at a press conference on Thursday.

Talas added that political instability in the country has hampered the efforts of the Organization (WMO) to work with the Libyan government to improve these systems.

However, even robust early warning systems do not guarantee that all lives can be saved, Cloke said.

She told CNN that dam failures can be very difficult to predict, and they are fast and ferocious. “You have this massive volume of water sweeping through the entire city,” Klock said. “It is one of the worst types of floods to ever occur.”

While dams are usually designed to withstand relatively extreme events, that is often not enough, Klock said. “We have to prepare for unexpected events, and then we put climate change at the top of the list, and this exacerbates these unexpected events.”

The threat that climate-fueled extreme weather poses to infrastructure – not just dams, but everything from buildings to water supplies – is a global threat. “We are not prepared for the extreme events coming our way,” Klock said.