Nearly half of the sinkhole accidents that occurred in the past five years resulted from damaged sewer pipes.

According to data submitted by Democratic Party lawmaker Jin Sun-mee on Wednesday, 45-point-four percent of the sinkholes that occurred from 2020 to 2024 resulted from damaged sewer pipes.

During those years, there were 867 instances of ground subsidence nationwide and 394 of them occurred because of damaged sewer pipes.

The second most common cause was poor backfilling, which accounted for 18 percent of the accidents.

Other issues included poor excavation work, which was responsible for nine-point-eight percent of the sinkholes; damage to other underground structures, which caused seven percent; and damage to water pipes, which caused four-point-eight percent.