Zero Sinkhole Occurrences!… Seongdong-gu Ensures Underground Space Safety with Smart Technology

▲Subsurface Road Void Exploration ▲Establishment of Safety Management System Including Underground Space Leakage Diagnosis ▲Operation of Sinkhole Prevention System Such as Continuous Replacement of Aged Sewers... First Nationwide IoT Underground Space Safety Management System Established in 2017 Annual Inspections, 22.2% of Total Sewers Replaced, Zero Sinkhole Incidents for Two Consecutive Years

Seongdong-gu, Seoul (Mayor Jung Won-oh) is making every effort to prevent sinkholes, including conducting subsurface cavity surveys on roads, as residents' anxiety grows due to the recent consecutive occurrences of ground subsidence in the urban area.

Seongdong-gu proactively established a sinkhole prevention system in 2017, prior to the enforcement of the Special Act on Underground Safety Management in 2018. It has set up a prevention framework in three major areas: ▲ subsurface cavity surveys on roads ▲ establishment of safety management systems such as underground space leakage diagnosis ▲ continuous replacement of aging sewer pipes, and has maintained stable operation to date. As a result, it has recorded zero sinkhole incidents for two consecutive years, including last year and this year.

The subsurface cavity survey on roads involves using Ground Penetrating Radar (GPR) equipment to inspect areas at risk of ground subsidence such as water and sewage pipes, subway stations, construction sites, and complaint sites. When cavities are discovered, immediate restoration work is carried out.

Although the Special Act on Underground Safety Management mandates surveys every five years, Seongdong-gu allocated its own budget to conduct subsurface cavity surveys on roads last year. This year, from June to November, subsurface cavity surveys are being conducted over a 61 km section within the district.

Following the introduction of the underground space safety management system (UGS) using IoT technology for the first time nationwide in 2017, the district newly implemented a more sophisticated underground space leakage diagnosis system using advanced technology since 2020 to monitor water supply leaks in real time. Sensors installed in water supply manholes detect abnormal signs such as vibrations caused by leaks, and if leakage is suspected, detailed inspections are conducted for prompt action.

The district is also promoting a full replacement project for aging sewer pipes, which are identified as a major cause of sinkhole accidents. Sinkholes mainly occur when old sewer pipes are damaged or cracked, causing sewage leakage that weakens the surrounding ground.

Accordingly, the district plans to fundamentally block sinkholes and prevent flood damage in advance by replacing aging sewer pipes to be completely leak-proof. Since starting full-scale replacements in 2014, it has replaced 68 km of aging sewer pipes, accounting for 22.2% of the total 306 km of sewer pipes in the area.

In addition, the district regularly dredges sewer pipes every year to prevent aging and is committed to thorough maintenance management.

Jung Won-oh, Mayor of Seongdong-gu, said, “We are leading sinkhole prevention through accurate and efficient underground space safety management using smart technology,” and added, “We will continue our tireless efforts to create a safer city Seongdong where all residents can feel more secure.”