After a Ukrainian underwater drone attack, Russia has effectively sealed off its naval base in Novorossiysk. The harbor entrance is blocked by barges and boom barriers, limiting the ability of its ships to head out to sea.
In Novorossiysk, Russian forces urgently closed access to the berths for warships after an SBU Ukrainian drone strike on a Russian Black Sea Fleet submarine, according to satellite imagery published by the Telegram channel Crimean Wind .
The images appear to show the harbor entrance blocked by barges and boom defenses. Officially, the move is designed to counter Ukrainian surface and subsurface drones, but it also has a practical downside for Russia: its ships can no longer rapidly enter the Black Sea to carry out combat missions.
The measures effectively isolate part of Russia’s fleet. With the entrance sealed, any maneuvering requires time and additional work to remove the barriers, sharply reducing the base’s readiness. Novorossiysk had long been seen as a “relatively safe” rear-area refuge for the Black Sea Fleet after its withdrawal from Crimea. That assumption is now under strain.
Norwegian analyst Thord Are Iversen notes that Russia has been using barges and underwater barriers in Novorossiysk for years. As an example, he posted a satellite image from September 4, 2024, showing the harbor entrance similarly blocked.
What’s different now, he notes, is that these measures come immediately after an actual strike that caused serious damage to a warship—less a preventive step than a reaction to vulnerability.
The diesel-electric submarine Kolpino (the sixth Project 636.3 boat) has previously been used by Russia for missile strikes. In 2017, it launched Kalibr missiles at targets in Syria, and since 2022 it has taken part in attacks on Ukraine.
