Lashed by the most severe rainfall in over 80 years, will Seoul’s deadly summer floods spark a risk reassessment

Seoul – the capital and largest metropolis of South Korea – was submerged by large scale flooding on the 8 August. Hit worst was the K-Pop landmark area of the Gangnam District, also one of the country’s most affluent residential areas. 

Social media filled with images of locals wading through knee-high water and cars submerged by the downpour. By the end of the storm, 2,800 buildings were damaged, 163 people were left homeless and most tragically nine people had lost their lives.

Before Gangnam was the drawcard of wealthy locals and K-Pop tourists, it was a common flood region – with over 75 percent of the land in Gangnam District having an altitude lower than 40 meters.

As such, construction for a new flood tunnel in nearby Banpo was completed in June, with Seoul major Oh Se-hoon proudly declaring at the time that Gangnam is now safe from a “once in 20 years” rain event.

This transpired to be hubris.

The new flood tunnel – created to channel rainwater in the areas near Nambu Bus Terminal to a nearby stream – was designed to handle 85 millimeters of rain per hour. The August downpour exceeded 110 millimeters per hour.

South Korea and its prosperous capital are savvy to natural disasters, but even the best preparation left the city short. In a country focused on public health and reactive to such events, was Asia’s 8th largest metropolitan area suitability equipped?

‘Not prepared’

“The current climate variability is an issue that we have never experienced in history, in terms of its magnitude and the speed of change,” In Chang Hwang, research fellow at the Department of Safety and Environment Research for the Seoul Institute, told StrategicRISK.

“The city of Seoul, like many other cities in the world, is not well prepared for tail events such as the recent flooding in Seoul.”

Sam Choi, director of Hankook Insurance Service (HIS) and head of the HIS Institute of Risk Management in Seoul stressed that compared to other local governments, Seoul has a large design capacity for rainwater pipeline.

“However, extreme flood disasters will become more frequent in the future, and there is a limit to preparing only for the expansion of flood protection facilities such as storm water pipes and drainage pump station,” says Choi.

Tom Larsen, senior director for insurance solutions at CoreLogic, says despite the magnitude of the flooding and the tragic loss of life, Seoul could expect to fully bounce back.

“Lost lives are not recoverable, but the resilience of societal infrastructure – utilities such as electricity, water and communications, roads and transportation especially commerce give promise to an expectation of a return to the past normal,” says Larsen.

“Assessing the city’s preparedness for major flooding requires an assessment of what happened and what didn’t happen. The apparatus that supports a city was able to recover from record flooding and this is a notable success. Any loss of life represents a continual need for more planning and an active response” he says.

‘Social learning’

South Korea’s 2019 Oscar-winning film Parasite depicts the rich Park family in their safe hillside home and the poor Kim family, who live in a ‘semi-basement’ – an apartment in Korea which is partly underground and usually rented to low-income residents.

In the film, we see a flash flood hit Seoul and the Kim family find themselves waist-high in flood water, their possessions ruined.

Just three days after the start of the real-life Seoul floods, city officials announced that such ‘Parasite-style’ semi-basements would be phased out as living locations.

However, owners have been given a rather generous 20 years to convert them into non-residential spaces such as storage or car parks. According to a survey conducted by the Seoul Institute in 2019, 45% of low-income households live in a basement floor.

So was such a reactive announcement the start of a new flood future for Seoul? Will the floods change the ways in which the city prepares for future floods?

“Definitely,” says Hwang emphatically. “Because of the recent floods, citizens are more informed about the impacts of climate change and have started requesting the government to take action.”

Hwang says there has been a period of “social learning” through a series of weather-related disasters during the last 10 to 15 years, such as another Seoul flood in 2011, a heatwave in 2018, and now this year’s floods.

“In response to the recent flooding, the city of Seoul and the local governments started to evaluate resilience of the current water management system to tail events and to allocate resources for the preparedness measures. A deep storm water storage-drainage facility is an example of what the city of Seoul is planning to implement,” says Hwang.

A key strategic implication of the floods is the reinforcement of the APEC (Asia Pacific Economic Cooperation) Disaster Risk Reduction Framework, says Larsen: “The four pillars of this framework are prevention, preparedness, response and rehabilitation. Evaluating the recent floods through these pillars helps us identify aspects that were working and aspects that need more support.”

Choi says disaster management in Korea was focused on prevention policies to prevent floods in advance. However, the intensifying change in the disaster environment is making it important not only to prevent, but also to manage measures in the preparation, response, and recovery stages, leading to measures to strengthen disaster resilience.

“Recently, the Ministry of Public Administration and Security and the Seoul Metropolitan Government are very interested in disaster finance such as insurance,” says Choi.

“Currently, wind and flood damage insurance for small businesses – a policy insurance programme that supports insurance premiums from the public sector – is about 9%, but the Ministry of the Interior and Safety has a goal of raising the insurance coverage rate to 35% by 2030,” he adds.

Climate change

As mentioned, Seoul new flood tunnel was supposed to protect against “once in 20 years” rain events. But two months after its completion the region was hit by the largest rainfall in 80 years.

What was once consideration a generational natural disaster, now looms as a more frequent threat. This invariable draws the conversation to climate change factors.

“Considering the level of climate change so far and the nature of ongoing carbon neutrality policy making, extreme weather events are inevitable, in theory at least, for the foreseeable future,” says Hwang.

“The city of Seoul together with the national government, therefore, should take a more balanced approach to climate change. The current floods tell us the importance of reducing vulnerability and enhancing equity and social justice, which have not been adequately considered in Korea,” adds Hwang.

Larsen says that the August flooding in Seoul reinforces the vulnerability that our cities and society have to weather disasters, and the increased weather volatility expected from climate change is expected to deliver more frequent occurrences of extreme events.

For APAC risk managers, the story of Seoul’s August floods demonstrates that even rich cities, with large flood prevention investments, can fall foul of our increasingly unpredictable climate.