Underwater search using scent dogs is a method of locating missing persons in water incidents by detecting decaying gases rising to the surface. (Yonhap)
GOYANG, Aug. 9 (Korea Bizwire) – On a muggy afternoon at the Haengju Ferry Terminal near the Han River, a specially trained dog named Alpha boarded a small boat, ready to demonstrate a groundbreaking technique in underwater search and rescue operations.
Alpha, a scent evidence dog belonging to the Gyeonggi Northern Provincial Police Agency, is part of a pioneering effort to locate submerged human remains using canine olfactory prowess.
The August 8 training exercise marked the first of its kind in South Korea, bringing together law enforcement agencies and civilian organizations to explore this innovative approach.
Before Alpha’s deployment, trainers had submerged a steel box containing a pepper shaker-sized sample emitting the odor of human remains at least two meters below the river’s surface.
Alpha’s task was to detect the decomposition gases rising from the water — a challenge that seemed daunting given the river’s murky waters and distinctive aquatic smell.
As the boat glided across the water, Alpha, alert and focused, began to bark decisively after just a few minutes.
“The dog has detected the scent of decomposition gases carried by the wind,” a police official explained. Guided by Alpha’s intensity of barking and the movement of its tail and ears, the handler steered the boat.
Within about 10 minutes, they pinpointed the target location with remarkable accuracy, despite being several dozen meters from the dock.
The demonstration highlighted the potential of scent evidence dogs in water-based search operations. Following Alpha’s discovery, an underwater drone confirmed the location of the submerged mannequin and sample, which divers then retrieved.
This training initiative, the first of its kind nationwide, brought together scent evidence dogs from five provincial police agencies, along with participants from the Coast Guard, the Korea Kennel Federation, and the Marine Corps Veterans Association.
In total, about 10 detection dogs took part in the exercise.
The principle behind this method lies in the behavior of decomposition gases. As a submerged body decays, it releases gases that are lighter than water molecules and rise to the surface.
While imperceptible to humans, these gases can be detected by dogs, whose sense of smell is estimated to be at least 10,000 times more acute than that of humans.
A sniffer dog climbs into a boat to explore the water surface during an underwater search drill using sniffer dogs at Haengju Naruteo in Goyang-si, Gyeonggi Province, on Thursday afternoon. (Yonhap)
This approach has shown promise internationally. In May 2019, a German civilian search dog successfully located victims of a tourist boat collision in Budapest, Hungary.
“We are gradually increasing the difficulty of the training by reducing the sample size and increasing the depth,” said a police official. “Given the width of the Han River, we would need to deploy multiple search dogs simultaneously in a real operation.”
The chosen training location is significant. Over 80% of underwater fatalities in northern Gyeonggi Province between 2021 and 2024 were discovered between Banghwa and Gimpo bridges.
This area, with its underwater weirs and tidal patterns, often prevents bodies from being swept downstream or out to sea, creating ideal conditions for canine searchers.
As the exercise concluded, police officials expressed optimism about the future of this program. “We will continue to research and develop this joint operation of scent evidence dogs and drones as part of our advanced scientific policing initiatives,” a spokesperson said.
“Our goal is to apply these techniques in real missing persons cases, enhancing our ability to bring closure to families and loved ones.”
Lina Jang (linajang@koreabizwire.com)
