Two sinkholes appeared in busy areas of Seoul on March 28, lending urgency to the problem of sinkholes, which threaten public safety.

In Sinchon, a 15-ton truck fell sideways as the ground gave way below it, and in Samseong-dong a motorcyclist was injured when his motorbike hit a sinkhole. In February, two pedestrians were injured in Yongsan when the pavement sank below them. Last year, sinkholes that appeared around the Lotte World Tower construction site also caused widespread fear.

Authorities explain that sinkholes occur due to improper construction or aging sewage and water pipes. A review of past sinkhole incidents confirms that aging sewer pipes are to blame for the majority of incidents. According to Seoul City, some 85 percent of the 3,205 sinkholes that appeared between 2010 and the end of last year were attributed to leaking or broken sewer pipes. Water from the pipes carries away the soil, creating a void in the soil and making the ground susceptible to sinkholes.

What is scary is that nearly 48 percent, or about 5,023 km, of sewer pipes in Seoul are more than 30 years old. An inspection last year by the Environment Ministry of 1,637 km of sewer pipes 20 years or older throughout the country found one vulnerable spot per kilometer.

As a city’s infrastructure ages, the possibility of accidents due to failures or breakdowns increases. In fact, the problem of sinkholes is not unique to Seoul ― they are being reported in major cities around the country. Yet many city and regional governments report budgetary constraints in replacing the aging pipes that are the major cause of sinkholes.

If this is the case, the central government should step in. For example, the newly created Ministry of Public Safety and Security could be charged with handling the sinkhole problem, including conducting geological surveys to identify vulnerable spots.