The tragedy of the campers along the Imjin River, who were swept away in a flash flood caused by the unannounced release of millions of tons of water from a dam in North Korea brings a sense of hopelessness at the lack of preparedness among South Korean officials, state agencies and the military for any such emergency. It is unbelievable that an early-warning device on the river for sudden rises in water levels simply failed to go off.

The early-warning device on the Pilseung Bridge in Yeoncheon triggers sirens along the Imjin River if its water levels exceed 3 m. A component called an RTU that is part of the early-warning device failed to relay information as it was designed to do. The RTU went dead at 10:52 p.m. on Saturday night, when the water level at Pilseung Bridge stood at 2.3 m, but the water began rising at 2:10 a.m. on Sunday and breached the 3 m level at 3 a.m.

A control center at the Yeoncheon district office has monitors that show the water levels at three different points along the Imjin River and a radar gauge displaying the water level in numbers. But the four officials on night duty were completely unaware of the situation.

A soldier on sentry duty at Pilseung Bridge reported the rising water levels to headquarters at 2:50 a.m. This information was passed up the chain of command to the Joint Chiefs of Staff, but the military did not think to notify the Korea Water Resources Corporation, Yeoncheon fire department or police. In fact, even a tank unit that was training downstream was oblivious to the alert. It was not until 5:15 a.m. that the unit began evacuating after a sentry notified it of the rising water level. As a result, one tank ended up submerged.

Campers along the shores of the Imjin River notified the nearest fire station at around 5:15 a.m., while the police, Yeoncheon and the KWRC reportedly found out about the situation between 5:24 and 6:10 a.m. It was 7:20 a.m. when the KWRC finally contacted the company that maintains the early-warning devices and got them to sound their sirens. But the campers had been swept away by the rapid current more than two-and-a-half hours earlier.

The middle and lower parts of the Imjin River, Yeoncheon, Munsan and Dongducheon are often hit by floods. In 1996, 1998 and 1999, flooding caused the deaths of 230 people and led to W1.6 trillion (US$1=W1,233) in property damage. On top of that, North Korea began building the Hwang River Dam in 2000 and started collecting water in April last year. Experts have pointed out since 2002 that the Hwang River Dam could end up being used as a weapon. Even during construction, North Korea opened the sluice gates of the Hwang River Dam without notice, causing damage to South Korean fishermen downstream. In September 2006, South Korea began constructing the Gunnam Dam below the demilitarized zone to prepare for sudden discharges by North Korea.

As long as tensions continue between North and South Korea, we must plan, prepare and work under the premise that a worst-case scenario is possible. North Korea is said to have discharged 40 million tons of water this time. The Hwang River Dam is estimated to hold between 300 million to 400 million tons of water. What would happen if North Korea discharged all of it at once? Even if the Gunnam Dam is completed next year, it can only hold 71.6 million tons of water. That means a sudden discharge of huge amounts of water by North Korea would lead to horrific consequences downstream.

The residents along the Imjin River must have been tremendously afraid when learned about the lack of readiness of the KWRC, military and government.