Confirmed: Latest Black Sea Ship Strikes Move Closer to Bulgaria’s Territorial Waters

The latest strikes on commercial vessels in the Black Sea occurred in Bulgaria’s contiguous zone, closer to its territorial waters than last week’s attacks, which took place farther out in the country’s Exclusive Economic Zone.

The two vessels were hit overnight, exactly one week after the ALFA WATAN and ABLE came under attack. In both incidents, one ship sank while the other stayed afloat. This time the Guinea-Bissau-flagged HS DIGNITY sank, with 11 of its crew missing and five rescued, while the Maltese-flagged, Ukrainian-owned CHELSEA 3 was hit by three drones and all 15 of its crew were rescued. However, while last Tuesday’s strikes occurred some 70 to 80 nautical miles offshore, the latest attacks took place 17 nautical miles from Krapets, where the HS DIGNITY went down, and 18 nautical miles from Byala, where the CHELSEA 3 was struck. That places them in the contiguous zone, one maritime area closer to Bulgaria’s territorial waters.

The legal status of these maritime zones is governed by the UN Convention on the Law of the Sea (UNCLOS) and Bulgaria’s Law on the Maritime Spaces, Inland Waterways and Ports. Beyond the internal waters, these rules set out three successive zones, each giving the state a different level of sovereignty and control.

The first is the territorial sea, also known as territorial waters. It stretches 12 nautical miles, or about 22.2 kilometers, from the baselines along the coast. This area forms part of Bulgaria’s national territory. The state exercises full sovereignty there, including over the water column, the seabed and subsoil, and the airspace above. Foreign ships may pass through these waters under the “right of innocent passage”, provided they comply with Bulgarian law.

Beyond the territorial sea lies the contiguous zone, which extends from the 12-nautical-mile boundary to 24 nautical miles from the baselines. This adds another 12 nautical miles, bringing the outer limit to about 44.4 kilometers from the baselines. The zone is not national territory, but Bulgaria has specific enforcement powers there. It can exercise the control needed to prevent and punish violations of its customs, fiscal, immigration and sanitary laws committed on its territory or in its territorial sea. The latest attacks, 17 nautical miles off Krapets and 18 nautical miles off Byala, occurred within this zone, about five to six nautical miles beyond the outer limit of Bulgaria’s territorial waters.

The third area is the Exclusive Economic Zone, which begins at the outer edge of the territorial sea and under international law can extend up to 200 nautical miles from the baselines. The contiguous zone lies within it. Because the Black Sea is relatively narrow, Bulgaria’s zone falls well short of that maximum. Its boundary with Turkey was largely set by a 1997 agreement, while the maritime border with Romania has still not been fully delimited.

In the Exclusive Economic Zone, foreign vessels enjoy freedom of navigation and overflight, much as on the high seas, though the zone is not legally part of the high seas. Bulgaria nevertheless holds sovereign rights to explore, exploit and conserve living resources, such as fish, and non-living resources, such as oil, natural gas and seabed minerals. Its jurisdiction also covers marine scientific research, the construction of artificial islands and installations, and protection of the marine environment.

The attacks on the ALFA WATAN and ABLE took place some 70 to 80 nautical miles offshore, in waters where Bulgaria holds only economic rights. The latest strikes, on the HS DIGNITY and the CHELSEA 3, came much closer to the coast, inside the zone where Bulgaria can act to enforce its customs, immigration and border rules.