Pilsun Park of Gwangju City Council: "Sewage Facilities Are the Leading Cause of Sinkholes"

Analysis of the '2025 Gwangju Underground Safety Management Plan'
64.4% of Ground Subsidence Caused by Sewage Facilities
65% of Sewage and 53% of Water Supply Pipelines Over 20 Years Old
"Urgent Need for Improvement of Water and Sewage Facilities and Comprehensive Management of Underground Infrastructure"

Pilsun Park, Gwangju City Councilor.

Pilsun Park, a Gwangju City Councilor (Democratic Party of Korea, Gwangsan District 3), stated on April 23, "More than half of the causes of sinkholes (ground subsidence) in Gwangju are due to damage to sewage facilities, and the aging of underground infrastructure is the key background for the increase in sinkholes."

According to the "2025 Gwangju Underground Safety Management Plan" submitted to Councilor Park by the Gwangju City Government, the main causes of sinkholes in the Gwangju area are underground facilities rather than natural factors.

Of the 107 sinkhole incidents that occurred in Gwangju over the past five years (2020?2024), 69 cases (64.4%) were caused by sewage facilities. In 2020, in particular, 55 sinkholes caused by sewer pipes occurred intensively due to the longest rainy season on record and heavy downpours.

The aging of underground infrastructure is also a serious issue. As of last year, of the total 4,117 km of water supply pipelines, 2,186 km (53%) were pipes older than 20 years, and 805 km (19.5%) were older than 30 years. For sewage pipelines, 3,006 km (65%) out of a total of 4,570 km had been in use for more than 20 years.

The geological characteristics of the Gwangju area have also been found to be vulnerable to sinkhole formation. In addition to the bedrock that forms the main base layer, heterogeneous strata such as silt, sand, and gravel are distributed near the Yeongsan River and Gwangju Stream, making the area susceptible to ground subsidence.

Councilor Park emphasized, "One of the government's key tasks is to establish a local government-centered management system for underground facilities," and added, "Since Gwangju is simultaneously carrying out large-scale underground construction projects such as Subway Line 2 and, in the future, the Gwangcheon-Sangmu Line, the city must serve as the control tower for underground safety management."

Park further stated, "Since sewage facilities account for the largest proportion among single causes, we must urgently conduct focused inspections and structural improvements according to a long-term plan, and strengthen the management of underground construction projects that can lead to major accidents." She also pointed out, "Instead of short-term restoration-focused responses, it is necessary to establish a sustainable urban safety system."

Meanwhile, the Gwangju Underground Safety Management Plan is a statutory plan established by the local government in accordance with the Underground Safety Act. The city has set its vision as "Gwangju, the safest underground in Korea," with major goals including reducing the ground subsidence rate by 10% compared to the previous year, establishing an integrated safety management system for underground facilities, and preparing a preventive system for underground safety.