Chong Won-o, the Democratic Party of Korea's candidate for Seoul mayor, said on the 19th at the third election countermeasures committee meeting that "in the past five years, Seongdong District had zero sinkhole accidents." However, records show Seongdong District filed ground subsidence (sinkhole) reports with the Ministry of Land, Infrastructure and Transport twice, in Aug. last year and in Sept. 2024. In fact, the only Seoul districts with no sinkhole reports over five years were Gwangjin District and Geumcheon District.
◇Seongdong District, which said there were no sinkholes… "accident reports" for two straight years through last year
According to the Ministry of Land, Infrastructure and Transport's underground safety information system on the 20th, a ground subsidence accident measuring 1.5 meters wide and 1.1 meters deep was reported in Sageun-dong, Seongdong District, on Aug. 10 last year. On Sept. 13, 2024, a ground subsidence accident measuring 3 meters wide and 1.3 meters deep was reported in Yongdap-dong, Seongdong District, marking two consecutive years.
Under the Special Act on Underground Safety Management, local government heads must report ground subsidence accidents to the Ministry of Land, Infrastructure and Transport (MOLIT). This applies when the affected area is at least 1 square meter or the depth is at least 1 meter, or when there are deaths, missing persons, or injuries due to subsidence. The Seongdong District accident reports both meet the depth criterion.
In the case of the accident that occurred last year, the restoration was completed, but the cause was reported as undetermined. The 2024 accident was found to have been caused by soil loss due to groundwater outflow from a construction site basement resulting from poor excavation work.
Since Chong was elected Seongdong District mayor in 2014, a total of six sinkholes have been reported in Seongdong District. Including one case each in last year and 2024, there were three cases in 2019 in Wangsimni, Majang-dong, and Sageun-dong, and one case in 2020.
Earlier, Chong said at the third election countermeasures committee meeting held at the Taepyeong Building campaign office in Jung District, Seoul, on the 19th, "In the past five years, Seongdong District had zero sinkhole accidents, zero flooding accidents, and zero major safety accidents," adding, "It clearly depends on what a leader chooses to prioritize." At the time, Chong did not specify the exact years for the past five years. However, given that Chong used the term "recent," it is highly likely that both last year and 2024 are included.
◇Gangnam District had the most sinkhole reports over five years… Gwangjin District and Geumcheon District had "none"
From 2021 to 2025, the 25 Seoul districts reported a total of 112 sinkhole accidents. Gangnam District reported the most with 15, followed by Songpa District (13), Seongbuk District (12), Dongdaemun District (7), Seodaemun District, Gangseo District, Yeongdeungpo District, Seocho District, and Gangdong District (5 each), Jongno District, Nowon District, Eunpyeong District, and Mapo District (4 each), Jung District, Jungnang District, Gangbuk District, Guro District, Dongjak District, and Gwanak District (3 each), Seongdong District and Dobong District (2 each), and Yongsan District and Yangcheon District (1 each).
So were there any districts with no sinkhole reports over the five years? Only two—Gwangjin District and Geumcheon District—had no sinkhole reports.
This year, five districts have reported sinkhole accidents: Jungnang District, Nowon District, Mapo District, Yangcheon District, and Gangseo District. Each reported one case.
Meanwhile, the Seoul Metropolitan Government commissioned the districts in 2024 and reported 50 high-risk sites with significant concerns over ground subsidence to the central government. According to this data, Gwangjin District had the most high-risk sites with 22, followed by Jongno District (9), Geumcheon District (7), Seongdong District and Guro District (3 each), and Gangnam District, Nowon District, and Mapo District (2 each).