Flooding in Seoul's Gangnam areas continues to cause problems

Social Affairs

Published: 09 Aug. 2022, 12:54

Flooding in Seoul's Gangnam areas continues to cause problems

Roads near Gangnam Station are flooded as heavy rain fell Monday evening. [MICHAEL LEE]

With record-breaking heavy rains causing flooding and damage in many parts of Seoul, the Gangnam area in particular is receiving attention for major drainage issues and the resulting flood damage.

Damage from floods could be seen throughout the capital city, but the damage was particularly severe in the area south of the Han River. Around 8 p.m. Monday, rainwater backflow around Gangnam Station flooded nearby roads and shops. At Woosung Apartments Intersection and Yangjae Station in Seocho District, muddy water flooded streets and turned the road into a river, forcing drivers to evacuate and climb atop their vehicles. Subway services in seven stations between Nodeul Station on and Sapyeong Station, all south of the Han River, were also suspended.

People stand on the bench of a bus station to avoid being submerged in rainwater while waiting for a bus in Seocho District, southern Seoul, Monday. [MICHAEL LEE]

Heavy precipitation was concentrated in the southern areas of Seoul, leading to the large amounts of flooding. According to the Korea Meteorological Administration, the accumulated precipitation was 417 millimeters (16.4 inches) in Dongjack District, 387 millimeters in Seocho District, and 367 millimeters in Gangnam District.

The topography amd geographical characteristics of the Seoul areas south of the Han River, characterized by low land and many rivers nearby, also had an impact. Gangnam Station is one of the areas most vulnerable to rainfall damages in downtown Seoul because of its bowl shape that dips more than 10 meters (33 feet) lower than its surrounding areas. Gangnam Station is 14 meters lower than the adjacent Yeoksam Station, collecting rainwater during torrential rains.

A car is partially submerged in water in Seocho District, Monday. [MICHAEL LEE]

Additionally, the construction of the nearby Gangnam-daero sewer pipe system was not done in a way that accounted for flooding. Similar drainage problems can be seen at the Banpo Stream and at the sewage culvert in the Samsung office building, all contributing to the area's frequent flooding.

The Seoul Metropolitan Government has been promoting drainage measures in the Gangnam area since 2015 in an attempt to solve these problems, but to no avail. The city government announced comprehensive drainage improvement measures in 2015 and began construction of a “drainage zone boundary adjustment” system spanning approximately 8 kilometers (5 miles) of Gangnam-daero. Disaster prevention facilities and additional sewage pipelines were also installed nearby. The Seoul government at the time announced that the total budget for the expansion of facilities in 33 major flood-prone areas including Gangnam Station was 1.4 trillion won ($1.07 billion).

Submerged cars are left abandoned near Gangnam Station Monday evening. [MICHAEL LEE]

“The budget for expanding drainage measure facilities has been fully invested as of 2022,” said an official from the Seoul Metropolitan Government. “The heavy rains that fell this time exceeded the disaster prevention limit, so there was an unpredictable aspect.”

BY MOON HEE-CHUL [lim.jeongwon@joongang.co.kr]