Two accidents reignite concerns over road safety

Underground cavities in two of the most crowded areas in Seoul resulted in two accidents on Sunday, once again leading to fears over public safety.

At around 6:40 a.m. on Sunday, the road next to COEX in southeastern Seoul caved in, bringing down a passing 19-year-old motorbike driver and his passenger. The hole, a meter (3.3 feet) wide and 30 centimeters (1 foot) deep, is assumed to have formed after an old water pipe running under the road began leaking, the Seoul Metropolitan Government said.

Later that day, a 25-ton tanker truck was tipped on its side toward the sidewalk in Sinchon, western Seoul, after the road underneath it suddenly collapsed. There were no reported casualties. The city government later explained that the section of the road had recently undergone maintenance work to repair a water pipe underneath it. The hole was provisionally filled, but was unable to withstand pressure from the truck.

A string of empty cavities found last year under the roadways in the Jamsil area in southeastern Seoul has since sparked mass concern over public safety, particularly as more accidents have occurred in highly trafficked areas in the capital city.

On Feb. 20, a young couple fell through the sidewalk in central Seoul after disembarking from a bus near Yongsan Station. When they stepped onto the sidewalk, the surface beneath them abruptly collapsed, causing them to plummet 3 meters below ground.

Analysts blamed insufficient construction management.

“With spring coming, a number of maintenance projects are being done on underground water pipes, but there aren’t any general management plans for those projects,” said Lee Soo-gon, a civil engineering professor at the University of Seoul. “That work should be done carefully after analyzing underground water flow and ground structure.”

City government data also points to old drainage pipes as a primary contributor to underground cavities. As of 2013, about 48 percent, or 5,023 kilometers (3,121 miles) of sewage pipelines were found to be 30 years old or more. Additionally, 2,714 of 3,205 road cave-ins from 2010 to 2014 - or 84.7 percent - were due to leaks from old sewer pipes, the city government said.

Last year, when the Ministry of Environment inspected 1,673 of the 37,564 kilometers of drain pipes that were 20 years old or more, it was found that there was a heightened risk for an underground cavity in the road roughly every kilometer.

The municipal government and the Ministry of Environment are planning to replace old water pipes one by one.

BY KANG IN-SIK, KIM BONG-MOON [kim.bongmoon@joongang.co.kr]