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Silent danger beneath the waves
Ukrainian Navy divers navigate a treacherous underwater landscape in the Black Sea, where thousands of mines and unexploded ordnance lie scattered across the seabed. The hazards, left behind by Russia's full-scale invasion, threaten both military and commercial vessels, yet their exact number and locations remain unknown.
The legacy of war at sea
Sea mines, deployed by Moscow early in the conflict, are designed to remain active for decades. Unlike land mines, they drift with currents, making them unpredictable. Last summer, three swimmers off Odesa's coast were killed by drifting explosives, underscoring the real-world danger.
Commander "Fox," who leads the navy's mine countermeasures group, estimates the number of sea mines in the thousands. But the threat extends beyond mines. When the Kakhovka dam collapsed in 2022, missiles, artillery shells, and land mines were swept downstream, adding to the underwater arsenal. "If we include all unexploded ordnance-missiles, shells, bombs-the total is many times higher," Fox said.
Balancing risk and necessity
Despite the peril, Ukraine's maritime export corridor remains operational. Merchant ships continue to navigate the waters, generating critical revenue-over two-thirds of Ukraine's agricultural exports, worth roughly $9 billion, pass through the Black Sea. Navy spokesman Dmytro Pletenchuk noted that commercial operators are willing to accept the risks, as evidenced by steady vessel traffic.
Ukraine has achieved a rare parity with Russia in the maritime domain. While Moscow dominates on land and in the air, its naval strategy-relying on sheer numbers-has faltered. In 2024, Russia withdrew its last patrol ship from occupied Crimea, and its fleet now avoids venturing far from port, fearing Ukrainian aerial strikes. "Naval warfare is technological," Pletenchuk said. "You cannot overwhelm an area with 'meat.'"
The painstaking work of de-mining
Divers like 31-year-old Vitalii operate with extreme caution. "We move slowly, quietly, and precisely," he said, mimicking the deliberate motion required to avoid triggering a mine. The process is agonizingly slow: divers advance in short bursts, pausing frequently, and may take hours to cover just 20 meters.
Before any de-mining begins, the team must first identify the object. The seabed is littered not only with Russian mines but also with World War II-era bombs and other unexploded ordnance. Mines fall into two categories: contact mines, which detonate on impact, and influence mines, which react to changes in sound, pressure, or magnetism. Large ships are particularly vulnerable to magnetic mines, which lie dormant until a vessel's magnetic field triggers them.
"The mine lies on the bottom and explodes when a big vessel approaches. Until that moment, it just waits."
Commander "Fox," Ukrainian Navy
Two divers approach each device in silence, using closed-circuit rebreathers to avoid creating bubbles that could trigger sensors. The first step is disabling the mine's sensors with controlled explosions from a safe distance. Only then can divers move closer to decide whether to relocate or destroy the device. The entire operation spans two days, involves 20 personnel, and is conducted under constant threat of Russian missile or drone strikes.
Obstacles and uncertain progress
Active combat complicates de-mining efforts. During air raids, GPS signals are scrambled, rendering sonar readings unreliable. Fox described the risks bluntly: "Everything can go wrong."
Vitalii recalled an incident where sonar detected an unknown object moving toward him. His initial fear-an underwater drone-was replaced by relief when he realized it was a pod of dolphins. "Beautiful, yes," he said. "But not at that moment."
In 2025, Ukraine's de-mining group neutralized over 50 mines, a small fraction of the total. The British Navy donated two mine-hunting vessels in 2023, but they remain stationed in the UK due to the high risk of deploying them in the Black Sea. With no ceasefire in sight, the vessels are unlikely to be used anytime soon. Under current conditions, Vitalii estimates clearing the seabed could take decades.
A lifeline for Ukraine's economy
Maritime exports are a financial lifeline for Ukraine, and their importance will only grow as the war drags on. Despite the dangers, divers like Vitalii continue their work, inching toward each mine with calculated precision. For now, the Black Sea remains a battleground not just for ships, but for the unseen threats lurking beneath the surface.
