BERLIN — European leaders said Tuesday they believed dual explosions that damaged pipelines built to carry Russian natural gas to Europe were deliberate, and some officials blamed the Kremlin, suggesting the blasts were intended as a threat to the continent.
But the episode is likely to mark a final end to the Nord Stream pipeline projects, a more-than-two-decade effort that deepened Europe’s dependence on Russian natural gas — and that many officials now say was a grave strategic mistake.
The pair of explosions Monday produced leaks in all three of the underwater Nord Stream pipelines that connect Russia and Germany, causing massive plumes of gas bubbles to break the surface of the Baltic Sea.
“These are deliberate actions, not an accident,” Danish Prime Minister Mette Frederiksen told reporters Tuesday. “The situation is as serious as it gets.”
Frederiksen said the explosions, just off the coast of the Danish island of Bornholm, were not “an attack on Denmark,” since they took place in international waters. But Danish military leaders on Tuesday dispatched the Absalon, one of their top-of-the-line frigates, along with other patrol ships, to guard the island. Danish Foreign Minister Jeppe Kofod was calling other NATO counterparts to discuss the situation, according to a senior European diplomat who was familiar with the conversations and who, like others, spoke on the condition of anonymity to talk frankly about internal security.
“We do not know the details of what happened yet, but we can clearly see that it is an act of sabotage,” Polish Prime Minister Mateusz Morawiecki told reporters Tuesday.
The act “probably marks the next stage in the escalation of this situation in Ukraine,” Morawiecki said. He was speaking at a ceremony to open the new Baltic Pipe undersea pipeline that gives Poland and its neighbors access to Norwegian natural gas. The project was intended to reduce dependence on the gas that once flowed from Russia.
Russia denied responsibility for the damage. The Russian government is “extremely concerned,” Kremlin spokesman Dmitry Peskov said Tuesday.
“The damage that occurred in one day simultaneously at three lines of offshore pipelines of the Nord Stream system is unprecedented,” the operating company, Nord Stream AG, said in a statement. It said it was working with local authorities to assess the extent of the damage, along with the cause.
Five European officials with direct knowledge of security discussions said there was a widespread assumption that Russia was behind the incident. Only Russia had the motivation, the submersible equipment and the capability, several of them said, though they cautioned that they did not yet have direct evidence of Russia’s involvement.
“No one on the European side of the ocean is thinking this is anything other than Russian sabotage,” said a senior European environmental official, speaking on the condition of anonymity to discuss internal thinking about the leak.
One official said it might have been a message to NATO: “We are close.” Another said that it could be a threat to other, non-Russian energy infrastructure, since so many pipelines crisscross the Baltic Sea, including the one inaugurated Tuesday. A third noted that crucial internet data cables lie along the bottom of the sea, and there have been long-standing concerns that Russia has a submersible program that could cut them, causing communications chaos around the world.
Swedish police opened an investigation into “sabotage,” a spokesman for the Swedish public prosecutor’s office, Karl Jigland, said. Germany and Denmark were also investigating.
Although gas was not being sent to Europe through the pipelines, there appeared to be a significant amount that remained in the pipes, raising concerns about possible environmental harm from methane — the main component of natural gas and a major contributor to climate change when it manages to reach the atmosphere.
Danish Climate Minister Dan Jorgensen told reporters that it might take at least a week to halt the flow of gas to the surface of the Baltic Sea.
Two of the damaged pipes are part of Nord Stream 1, which was previously a major transmission line of Russian natural gas to Germany, Poland and other European nations. Russia decreased and then stopped the flows through Nord Stream 1 earlier this year. The Kremlin blamed technical problems. European leaders, including European Commission President Ursula von der Leyen, accused the Kremlin of using fossil fuels to “blackmail” countries supporting Ukraine.
The third leak is part of the newer Nord Stream 2, a project that Germany froze as Russia launched its invasion.
The Swedish National Seismic Network (SNSN) registered two distinct blasts in the vicinity of Bornholm on Monday. Automatic monitoring picked up the first blast, which registered the equivalent of an earthquake magnitude of 1.8, at 2:03 a.m. A second, larger blast, registering an equivalent earthquake magnitude of 2.3, came at 7:04 p.m.
“The location of the second blast is five or six kilometers away from where the Swedish Maritime Administration puts the gas leak,” said Bjorn Lund, director of the Swedish seismic network. He noted that the complexity of the geographic area means there is some deviation in any estimated distance.
SNSN often registers blasts in the area when the Swedish navy conducts explosive exercises, Lund said, and consequently has a lot of data on the surrounding area.
“That [comparative data] make us even more sure that these are blasts and not earthquakes or landslides or something more natural,” he said. “What we see now is very similar to what we recorded for these navy blasts.”
The German Research Center for Geosciences confirmed similar findings to The Washington Post, saying it was certain that the seismic disturbances were not caused by a naturally occurring earthquake.
Imagery provided to The Post by Planet Labs, an Earth imaging company, showed methane bubbles appearing on the surface as early as 9 a.m. Monday, following the first recorded blast.
An adviser to Ukrainian President Volodymyr Zelensky said Russia was likely to blame for the new leaks.
“‘Gas leak’ from NS-1 is nothing more that a terrorist attack planned by Russia and an act of aggression towards EU,” the adviser, Mykhailo Podolyak, tweeted.
Secretary of State Antony Blinken said Tuesday that the United States was aware of unverified reports that the leaks may be the result of “an attack or some kind of sabotage.”
“If it is confirmed, that’s clearly in no one’s interest,” he told reporters at the State Department. “What’s critical is that we are working day in, day out, both on a short-term basis and a long-term basis, to address energy security for Europe and, for that matter, around the world,” he said.
Blinken said U.S. efforts include surging liquefied natural gas to Europe, increasing U.S. oil production and tapping into the Strategic Petroleum Reserve. He insisted that the leaks, whatever the cause, would not have a significant impact on Europe’s “energy resilience.”
A spokesman for the European Commission said that although gas supplies were not at risk, officials were concerned about potential environmental damage.
“This hasn’t affected the security of supply as yet,” spokesman Tim McPhie said. “Deliveries have been zero on Nord Stream 1 anyway, and Nord Stream 2 is not yet authorized to operate. We are also analyzing the potential impact of these leaks of methane, which is a gas which of course has considerable effects on climate change, and we are in touch with the member states about the potential impact on maritime navigation.”
The potential environmental impact was hard to assess, experts said, because the amount of methane actually released into the atmosphere depends on a wide range of variables. Methane is more than 80 times more potent than carbon dioxide for the first 20 years after it is released into the atmosphere. But water is able to absorb at least part of the gas when it is released underwater.
“We don’t know the volume of methane coming out, we don’t know how long it’s going to continue, we don’t know the size of the bubbles that are being formed as it comes out,” all of which is key to understanding how much methane might be released, said Carolyn Ruppel, chief scientist for the U.S. Geological Survey’s Gas Hydrates Project.
Scientists said that the relatively shallow depth of the pipeline — roughly 75 yards below the water’s surface — was concerning.
“In a shallow situation like this, it is much more likely that substantial amounts of the methane can reach the atmosphere,” Ruppel said.
The Nord Stream operator has not said how much gas was in the pipelines at the time of the explosions.
Jean-Francois Gauthier, vice president of measurements with the emissions monitoring group GHGSat, said that although information was limited, a “conservative estimate … is that these leaks combined are likely to be in excess of 500 metric tons per hour at the time of breach” and would drop over time if the flow was stopped upstream.
That would be “an order of magnitude more,” he said, than the largest recorded U.S. leak at Aliso Canyon in California in 2015 to 2016, which was about 50 tons per hour at its peak.
Birnbaum reported from Washington and Ilyushina from Riga, Latvia. Kate Brady in Berlin, Beatriz Rios in Brussels and John Hudson in Washington contributed to this report.
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