Dam disaster highlights climate and safety concerns5 January 2024
The recent Libyan dam failures have highlighted how climate change continues to intensify the severity of weather-related disasters, and why dam safety should be pushed to the top of the agenda worldwide. Report by Suzanne Pritchard.
Almost a quarter of Africa’s deadliest weather-related disasters since 1900 are reported to have occurred in the past two years. And the most recent catastrophe in Libya, where devasting floods amassed a death tally of thousands, was the seventh to have killed at least 500 Africans since 2022. According to meteorologists, climate change is, and will continue to increase, the severity of African weather disasters.
On 10 September 2023, a medicane (a Mediterranean hurricane-like system) reached its peak in northeastern Libya with strong winds of 70-80km/h. Called Storm Daniel, it also brought 150-240mm of torrential rains that caused flash flooding in several cities. The port city of Derna was one of the hardest hit and received more than 100mm which far exceeded its average monthly rainfall of less than 1.5mm for September.
Such record-breaking rainfall trigged the collapse of the Abu Mansur and Derna dams along a usually dry riverbed (wadi) and as this floodwater, sometimes up to 7m in height and 100m wide, tore through the city of Derna, it led to the collapse of many roads and buildings, even sweeping them out to sea.
Both dams were built in the 1970s. Situated about 14km away from the city, Abu Mansour was over 70m high and could hold up to 22.5Mm3 of water, while the Derna dam, also known as Belad, was much closer to the city and could hold 1.5Mm3.
Estimates suggest that up to 100Mm3 of water filled the valley prior to the collapse of the Abu Mansur dam, while it’s been claimed that in order to discharge the water entering the valley, the dam would have required a discharge capacity of 1200m3/sec, whereas its designed capacity was 170m3/sec.
In the aftermath of the disaster it’s still unclear how many people were killed as many bodies are believed to have been washed out to sea. Derna, with a population of 90,000 was the hardest hit town and estimated loss of life could be in the region of 20,000. At least 4000 people have been confirmed dead, with another 10,000 reported missing, while the Office for the Coordination of Humanitarian Affairs estimated that more than 880,000 people lived in areas impacted by the floods.
In the aftermath of the dam failures in Derna Valley on 11 September 2023. Courtesy Shutterstock, contributor: Seraj Elhouni
Tensions have flared in the wake of these tragic events with conflicting reports about how the emergency procedures were handled. Libya's National Meteorological Centre claims it issued early warnings for the extreme weather event 72 hours before its occurrence, and notified all government authorities by emails and through media urging them to take more care and preventive measures.
Other reports have highlighted how local residents were indeed evacuated away from the riverbed and seafront in Derna, as there were fears about rising sea levels, but many people were then reportedly moved into the centre of the city, and killed by later flooding. Although the Mayor of Derna (who later resigned) says he personally ordered evacuation three to four days before the disaster, other reports claim that officials told residents to stay put with no warnings of possible flooding. A Reuters report even mentions a Facebook post from the Water Resources Ministry that told residents not to worry, that the dams were in good condition, and everything was under control.
Hydrologist Abdul Wanis Ashour disputes the claim that the two Libyan dams were in good condition. Only last year he warned in an academic paper published in the Sebha University Journal of Pure and Applied Sciences, that if the dams were not maintained there could be a disaster in the Derna Valley basin.
Ashour has been researching the Derna dam system for 17 years and unearthed data that revealed the presence of numerous cracks in the dam, along with other worries about rainfall and repeated flooding. In his paper he asserted that the dams were unable to withstand a storm like Daniel and were at risk of collapse if faced with such large amounts of rainfall.
"The fragmentation of the country’s disaster management and disaster response mechanisms, as well as deteriorating infrastructure, exacerbated the enormity of the challenges,” Secretary-General of the World Meteorological Organisation (WMO), Professor Petteri Taalas, commented on the Libyan disaster. “The political situation is a driver of risk, as we are seeing in many countries currently."
Taalas was referring to the long-term political unrest in Libya where armed factions have been waging a war since Colonel Gaddafi was removed from power in 2011. It was such instability that is reported to have prevented a Turkish company from completing repairs to the two stricken dams.
Reuters says that authorities tried to repair the dams back in 2007 after a study by the country’s Water Resources Ministry acknowledged the gravity of their situation. However the Turkish company contracted to carry out the work was unable to complete it for security reasons, as the city had been besieged by warring factions for several years. Although a ministry spokesman has since said that even if the work had been carried out the dams would still have failed, as Storm Daniel exceeded their capacity, but acknowledged the damage would not have been so severe.
There are also various claims about funding of the repairs and how money was allocated. In 2021 Libya’s Audit Bureau said the Water Resources Ministry had failed to move forward with the dam maintenance and although US$2.45million had been earmarked for the work, only some of the money had been deducted and there was uncertainty about how this had been spent.
Water at the Heart of Climate Change is a joint initiative which will help countries in the Nile River Basin address climate-related risks that too often fall between the cracks.
Water at the heart
"The tragedy highlights the philosophy behind the Early Warnings for All initiative to improve the accuracy and availability of impact-based forecasts, and to ensure that they reach everyone and lead to action,” WMO’s Professor Taalas added.
The Early Warnings for All campaign was recently launched by UN Secretary-General António Guterres. WMO is partnering with the UN Office for Disaster Risk Reduction, the International Telecommunications Union, the Red Cross and a range of other partners to ensure that early warnings reach everyone and lead to early action. They warn that as global warming continues, the expectation is that there will be more extreme rainfall events, leading to more severe flooding.
Another initiative which has been funded and supported by the Kingdom of the Netherlands, is Water at the Heart of Climate Action - an ambitious partnership between the International Federation of Red Cross and Red Crescent Societies, The Netherlands Red Cross, the United Nations Office for Disaster Risk Reduction, WMO and the Systematic Observations Financing Facility (SOFF).
Maarten van Aalst, Director General of the Royal Netherlands Meteorological Institute said: “As a national Meteorological Institute, we see the rapid increase in weather extremes in our changing climate, and we realise that we need partnerships all across society to make sure our warnings lead to early actions. The Netherlands’ vulnerability as a low-lying delta is significantly reduced by the power of good data and predictions, and the ability to act on that information — from satellites to sandbags. Water at the Heart will strengthen our peers in the global south to deliver similar services.”
Water at the Heart aims to address climate-related risks that can too often fall between the cracks of most country-level water, sanitation, and hygiene policies. It will focus on practical, locally driven action to better anticipate disasters and prepare communities well in advance, combining local knowledge and global technology to help communities understand and act on the water-related risks they face - before they become disasters. The programme is focused on supporting the countries of Ethiopia, South Sudan, Sudan, and Uganda in the Nile River basin. These countries are not only among the least developed in the world but are also highly vulnerable to the impacts of climate change.
Furthermore, Water at the Heart will also use the latest science and technology to monitor and forecast weather and water-related hazards, and will invest in communications technologies to warn communities of what is coming and enable early action. As a result, this programme is a direct contribution to the implementation of the Early Warnings for All initiative. To ensure the implementation of this five-year partnership, the Government of the Netherlands has generously committed 55 million euros.
“The majority of hazards are water-related, particularly floods and droughts. Climate change will further increase the frequency and severity of these events. End-to-end early warning systems are critical to save lives and minimise the impact of disasters,” WMO Secretary-General Taalas said. “WMO is working with SOFF to close the basic weather and climate observation data gap and strengthen the foundational element of better data for better forecasts. Water at the Heart of Climate Action will make a tangible contribution to the Early Warnings for All initiative.”
Information from the World Meteorological Organisation can be found at https://public.wmo.int/en