Last Year's Flood Nightmare... What to Do About Retaining Wall Collapse and Underground Parking Flooding During the Rainy Season

Nationwide Monsoon Started Last Weekend, Rain Forecast Continues This Week
Sudden Heavy Rain Increasing Due to Climate Change... Rising Concerns Over 'Flood Disasters'

Starting from last weekend in Jeju Island, the full-scale rainy season has begun. In Seoul, the rainy season front moved north overnight, bringing rain.

The expected rainfall on the 26th and 27th is 50?150mm in Jeju Island, and 30?100mm in the metropolitan area, inland and mountainous areas of Gangwon, Chungcheong region, southern regions, the five western islands, Ulleungdo, and Dokdo. Until the 27th, most areas nationwide are expected to experience very heavy rain of 20?40mm per hour accompanied by strong winds, thunder, and lightning.

On the night of August 8 last year, a driver is evacuating after a vehicle was submerged on a road near Daechi Station in Gangnam-gu, Seoul. Photo by Yonhap News

According to the Korea Meteorological Administration, the probability that rainfall in July and August will be similar to or greater than the average is 40% each. The rainy season is also expected to be longer than usual, raising concerns that disasters caused by 'water bombs' such as road and underground parking lot flooding, retaining wall and embankment collapses, and landslides may recur.

Previously, in early August last year, when a sudden heavy rain occurred, three family members living in a semi-basement villa in Sillim-dong, Gwanak-gu, Seoul, were unable to be rescued from a flooded room and died. At that time, they had reported the flooding, but when the police and fire authorities arrived, the house was already filled with water.

Meanwhile, during the heavy rain caused by Typhoon Hinnamnor in September of the same year, seven out of nine residents who went to retrieve their cars from an underground parking lot of an apartment in Pohang, Gyeongbuk, died. The apartment residents where the accident occurred had heard an announcement from the management office instructing them to move their vehicles in the underground parking lot, and when they went out to move their cars, sudden flooding occurred in the underground parking lot, resulting in the tragedy.

Increase in localized heavy rain due to 'climate change'... Problems continue after the rainy season

Recently, sudden heavy rain is considered a variable in flooding incidents. In the past, the rainy season involved continuous heavy rain over several days, but recently, during the rainy season, there have been increasing occurrences of localized heavy rain that suddenly pours after periods of clear weather. Due to climate change over the past few years, the pattern of the rainy season is changing, making it difficult to predict when, where, and how much rain will fall.

In June of last year, the Tancheon Stream in Seoul overflowed, submerging a vehicle flood warning sign in water. Photo by Yonhap News

There is also a possibility of flooding in August, after the concentrated heavy rain has ended. About 30% of South Korea's annual rainfall is concentrated during the rainy season in June and July, but last August, an unusual heavy rain caused significant damage. On August 8?9 last year, 141.5mm of rain fell per hour in Dongjak-gu, recorded as a rainfall event with a frequency of over 500 years.

Subsequently, in October last year, the Seoul Metropolitan Government announced the establishment of the 'More Detailed Flood Safety Network Promotion Strategy (2022?2032)' and declared a major shift in flood control measures focusing on 'climate disasters.' The flood control performance target (rainfall processing target) was improved to handle heavy rain exceeding 100mm per hour.

Meanwhile, as heavy rain warnings expanded to Chungnam and Jeonbuk by dawn on the 26th, the Ministry of the Interior and Safety activated Level 1 of the Central Disaster and Safety Countermeasures Headquarters (CDSCH) at 3 a.m. on the 26th to respond to the heavy rain and raised the crisis alert level from 'Interest' to 'Caution.'

The CDSCH instructed related agencies to conduct preemptive control and evacuation guidance focusing on coastal areas, rivers, mountain valleys, and areas prone to landslides to prevent casualties. In addition, in case of flooding in underground spaces such as semi-basement houses and underground parking lots, rapid evacuation is advised, and for vulnerable groups with mobility difficulties such as people with disabilities and elderly living alone, public and private sectors are to cooperate actively to support swift evacuation.

This content was produced with the assistance of AI translation services.