Dongdaemun-gu 'Empty Space Under Road' Detection for Sinkhole Prevention

Subsurface Road Investigation Using Ground Penetrating Radar (GPR)... Immediate Action Upon Void Detection
Replacement of Damaged Sewers · Enhanced Safety Inspections at Excavation Sites

Dongdaemun-gu, Seoul (Mayor Lee Pil-hyung) announced on the 20th that it will use Ground Penetrating Radar (GPR) to detect voids beneath roads and prevent the occurrence of sinkholes.

‘Void exploration’ is the process of locating underground voids, which are one of the main causes of road subsidence. This measure was taken in response to residents' concerns following ground subsidence near the construction site of the Northeast Line urban railway around Korea University Station.

The district plans to conduct detection work over a total of 66 km, including construction sites and areas prone to frequent flooding where ground subsidence is a concern, adding an 8 km section of roads in the Northeast Line construction area where sinkholes have occurred, to prevent safety accidents caused by ground subsidence.

Vehicles equipped with Ground Penetrating Radar inspect beneath the roads, and restoration work begins immediately upon detecting any voids. In the event of ground subsidence, damage status and response measures are shared in real-time with relevant departments via SNS, and the Dongdaemun-gu Road Division’s rapid response team promptly dispatches to the site to take safety measures and carry out direct restoration.

To prevent ground subsidence caused by damaged sewage pipes, the district is continuously working with the Eastern Waterworks Office to replace aging water and sewage pipelines, while also strengthening safety management at excavation sites. Three excavation supervisors from the Dongdaemun-gu Road Division plan to patrol the sites regularly.

In September, the district will also investigate the presence of any abnormalities in the ground around large-scale construction sites together with external experts.

Lee Pil-hyung, Mayor of Dongdaemun-gu, stated, “This inspection will alleviate residents’ concerns about ground subsidence,” and added, “We will continue regular inspections to create a safe road environment where people can travel with peace of mind.”