As climate change continues to intensify weather patterns globally, cities in southern Europe are facing unprecedented challenges. The recent flood in Valencia, Spain, on October 29, 2024, serves as a grim reminder of the increasing risk. In a terrifying eight-hour period, a year’s worth of rain fell on Valencia, causing severe destruction and resulting in a death toll that has climbed to 95 people. This catastrophic event has reignited questions about Lisbon‘s readiness to face a similarly devastating flood. Portugal’s capital has experienced its share of severe flooding events over the years, and the city is taking extensive measures to reduce its vulnerability. But is Lisbon truly prepared? The short answer is no – like many cities that would be faced with the amount of torrential downfall that Valencia just received. Let’s take a look at the history of recent floods in Lisbon and what the city is doing to prepare for the worst.
Recent Floods in Lisbon
Lisbon is no stranger to intense rainfall and flooding. On December 7, 2022, the city experienced extreme flooding after receiving over 80 mm of rain in just 24 hours. The resulting deluge led to significant damage across the city, tragically claiming the life of a person trapped in a flooded basement home in Algés, in the municipality of Oeiras. A few days later, on December 12 and 13, another wave of heavy rain struck Lisbon and the nearby district of Setúbal. During this event, the Tapada da Ajuda weather station recorded an additional 65.6 mm of rain within three hours, while Almada in Setúbal measured 59.7 mm in a five-hour period. These floods resulted in widespread destruction, disrupting transportation and leading to countless emergency rescues.
One of the deadliest flooding events in Lisbon occurred on November 25-26, 1967. Known as the “great floods,” this disaster struck the Lisbon metropolitan area, impacting 14 municipalities and claiming between 500 and 700 lives, making it the deadliest flood in Portugal’s history. The rain was heaviest in the region between Estoril and Alenquer, with over 120 mm falling in just five hours, causing the Tagus River and its tributaries to rise by 3 to 4 meters. The floodwaters inundated homes up to their first floors, dragging debris, stones, and mud, while high tide further exacerbated the devastation. Many of those affected were recent rural migrants living in flood-prone areas, whose homes were swept away in the sudden deluge. With no flood alert system in place, the flood caught most people unaware, making it Portugal’s deadliest national disaster since the 1755 earthquake.
Current Projects to Combat Flooding in Lisbon
In response to increasingly frequent and severe flooding, Lisbon has implemented an ambitious drainage plan to mitigate future flood risks. The origins of the project date back to 2002, when the first calls for a comprehensive drainage system arose. In 2008, the planning was completed, and it took another seven years before Lisbon formally presented its €250 million drainage master plan. This plan includes constructing two massive collecting tunnels designed to divert excess rainwater away from the city’s streets and directly into the Tagus River.
The first and largest tunnel, extending 4.6 kilometers from Campolide to Santa Apolónia, collects rainwater from various key locations, including Avenida da Liberdade and Avenida Almirante Reis, alleviating pressure from overburdened drainage systems. The second tunnel, which spans 1.6 kilometers between Chelas and Beato, aims to provide additional flood protection. Both tunnels, with diameters of 5.5 meters, operate independently of Lisbon’s sewage system in order to ensure that rainwater flows uninterrupted into the river.
The current stage of construction focuses on the critical areas of Santa Apolónia and Avenida da Liberdade, with anticipated completion dates ranging from early 2025 to late 2026, although it is always hard to say when projects of this size will be completed. The tunnel systems are designed to create a vortex effect, redirecting water to prevent flooding in Lisbon’s low-lying Baixa district. Although the construction has caused some temporary disruption in the city, engineers and planners are optimistic that these tunnels will significantly reduce flood risks once completed.
The drainage plan also includes additional protective measures, such as retention basins in Ameixoeira and Ajuda and a rainwater infiltration system in Parque Eduardo VII. Smaller drainage tunnels, like the 350-meter tunnel near Oriente Station, offer further flood protection. These structures ensure a more distributed approach to flood management across Lisbon, enhancing resilience against future heavy rainfall events.
Lisbon Unveils 86 Emergency Meeting Points for Disaster Preparedness
In tandem with physical infrastructure improvements and the recent earthquake felt in Lisbon on August 26, 2024, Lisbon has bolstered its disaster preparedness strategy by designating 86 emergency meeting points throughout the city. These meeting points serve as safe havens for over 600,000 residents during crises, including floods, earthquakes, tsunamis, and fires. The selection process for these sites took into account various risk factors, including soil composition, seismic susceptibility, and proximity to essential emergency infrastructure.
These sites, developed in collaboration with local parish councils and Lisbon’s Municipal Civil Protection Service, offer citizens a safe location to gather with emergency kits until help arrives. Distinct signage will soon mark each meeting point for easy identification, ensuring that residents can quickly locate safe zones during a disaster.
To further enhance public preparedness, Lisbon has also launched the LxReSist platform, an online tool and mobile application designed to increase the city’s seismic resilience. LxReSist provides residents with building-specific information on seismic vulnerabilities and encourages structural reinforcements to improve building safety. With many tourists visiting Lisbon each year, the platform will soon be available in multiple languages to ensure accessibility for all. The platform empowers Lisbon’s residents and visitors with practical information to help them make informed safety decisions in the face of natural disasters.
Ongoing Infrastructure Improvements
Lisbon’s €150 million drainage project is currently halfway completed and promises substantial improvements to the city’s flood resilience. Mayor Carlos Moedas emphasized the importance of these drainage works, particularly in light of the devastating December 2022 floods. Preliminary evaluations have revealed that 5% to 10% of Lisbon’s municipal buildings may require structural reinforcements to withstand earthquakes, another natural hazard that the city is preparing for as part of its broader disaster readiness strategy.
Beyond flood management, Lisbon has installed two tsunami warning sirens and plans to add eight more over the coming years. These systems form part of the city’s comprehensive emergency response strategy, which also includes an SMS alert service that notifies residents of emergencies and provides safety recommendations.
What You Can Do to Prepare for a Major Flood in Portugal?
While Lisbon’s ongoing drainage improvements and emergency infrastructure enhance its flood resilience, residents can also take individual steps to prepare for extreme weather events. The following recommendations provide practical ways to stay safe:
1. Prepare an Emergency Kit – Keep essential items such as water, non-perishable food, a flashlight, a first-aid kit, and important documents in a waterproof bag.
2. Stay Informed – Register for Lisbon’s SMS alert service by sending a message with the text “AVISOSLX” to 927 944 000. Staying informed can help you act quickly in an emergency.
3. Know Your Emergency Meeting Point – Familiarize yourself with the nearest emergency meeting point designated by the city and ensure that all family members know the location.
4. Elevate and Protect Valuables – If you live in a basement or a low-lying area, consider elevating furniture and valuable items to prevent water damage in case of flooding.
5. Move Your Car to Higher Ground – Make sure that your car is not parked in a low-lying area prone to flooding when torrential downpours occur. One area in Alcântara, for example, across from Alcântara Terra train station, floods each time there is significant rainfall and should always be avoided during bad weather events. We only recommend doing this if it can be done days before a major weather event or perhaps as a regular practice. Do not attempt this during the middle of heavy rainfall.
5. Review Insurance Policies – Check your insurance coverage for flood damage and consider purchasing additional coverage if you live in a high-risk area.
In Portugal, home insurance is mandatory for homeowners with a mortgage, although it is not required for those living in rented properties. Landlords, however, are generally responsible for obtaining at least a minimal insurance level on rental properties, covering the structure itself, and they may factor this expense into rental pricing. Homeowners and landlords alike often consider additional coverage options to protect against the wide range of risks that properties in flood-prone areas might face.
There are two main types of building insurance available in Portugal: fire insurance and multi-risk insurance. Fire insurance, known as seguro de incendio, is the minimum requirement for property owners and protects against fire damage, with most policies also extending to cover natural disasters like floods, storms, and lightning strikes. For more comprehensive coverage, property owners can opt for multi-risk insurance, or seguro multirriscos, which includes additional protections, such as public liability coverage. Many policies also offer contents insurance as an add-on, safeguarding personal belongings within the property. The cost of home insurance varies based on factors like property value, the level of coverage chosen, and the specific risks associated with the location.
6. Create a Family Emergency Plan – Designate a safe spot within your home, plan an evacuation route, and ensure that all family members know the procedures for evacuating during a flood.
Final Thoughts
As demonstrated by the tragic flood in Valencia, extreme weather events can lead to catastrophic loss of life and property in a matter of hours. Lisbon has recognized the urgency of preparing for such disasters and invested in advanced drainage infrastructure and establishing comprehensive emergency plans. The city’s dedication to enhancing its flood resilience is evident in its ambitious drainage plan, newly established emergency meeting points, and digital preparedness platforms like LxReSist.
Despite these advances, the unpredictability of climate change and the increasing frequency of extreme weather events mean that no city can ever be fully immune to natural disasters. While Lisbon is making commendable progress in its preparations, continued vigilance, public education, and infrastructure development remain essential to ensure the safety of its residents. In a world where monster floods are becoming more common, cities like Lisbon must continue adapting to protect their communities.
