The Nord Stream pipeline leak was sabotage: What happens next?


The Nord Stream pipeline leak was an act of  ‘sabotage’: Who might have done it, why, and what happens next?

It’s a mystery worthy of a Cold War-era spy novel: A pair of critical natural gas supply lines linking Russia to Europe are hit by unexplained underwater explosions in the Baltic Sea. The culprit is unknown, as is the precise cause. There are accusations of sabotage and fears for the environment, as the ruptures send giant bubbles of methane to the surface of waters off the Danish and Swedish coasts. Theories abound about who might have done it and why, as do fears about what the explosions could mean for Europe and for Russia.

Except this isn’t fiction. Late on Monday, seismic stations in Sweden, Norway and Finland detected the detonations in the Baltic; it soon became clear that two pipelines that bring Russian natural gas supplies to Europe had been damaged. Known as Nord Stream 1 and Nord Stream 2, the pipelines run from Russia to Germany. Although supplies via the former had been halted by Russia in August, and the latter wasn’t yet operational, both pipelines contained pressurized gas. Three different ruptures were found — two on the Nord Stream 1 pipeline, one on Nord Stream 2.

An accident — a pipeline hit by a passing ship’s anchor, for example — has been ruled out, given the size of the leaks. “It is now the clear assessment by authorities that these are deliberate actions. It was not an accident,” Danish Prime Minister Mette Frederiksen told reporters in Copenhagen on Tuesday.

Her assessment was echoed by the European Union’s top diplomat, Josep Borrell, who, in a statement on behalf of the 27-country bloc, said that everything points to a “deliberate act.” “Any deliberate disruption of European energy infrastructure is utterly unacceptable and will be met with a robust and united response,” Borrell warned, as governments and energy companies across the continent stepped up security around critical infrastructure.


The immediate impact on Europe’s energy calculus is limited — given that the Russian supply had already been shut off — but longer term, the damage could affect natural gas prices, feeding inflation and pressuring the continent, amid the ongoing war in Ukraine and an energy war with Russia.

Much remains unclear about the nature, cause and impact of the attack on the Nord Stream pipelines. Grid tackles some of the core questions here:

How much gas was in the pipelines?

Nord Stream 2 has not yet been put into operation; the German government had halted the project just two days before Russia invaded Ukraine. But the pipeline still contained a significant amount of natural gas — 177 million cubic meters, to be precise — which had been pumped through the pipeline in 2021 to bring it to the correct pressure for operations to begin. That’s a bit more than one day’s worth of the pipeline’s capacity, which totals 55 billion cubic meters per year.

Nord Stream 1 ceased operation earlier this year, but it also was filled with gas — possibly the same amount, though details have been hard to come by since the incident. A spokesperson for the company that owns the pipelines said there was a total of 300 million cubic meters of gas in the two-pipeline system when the ruptures occurred.

How dangerous is this for any vessels nearby?

The Danish and Swedish authorities have established a five-nautical mile exclusion zone around the affected areas, and as long as vessels in the area steer clear of that zone, this should not represent any danger. Were they to stray into the area, there is a chance they could lose buoyancy in the vicinity of the escaping gas, and there is also a possibility the plume could ignite, either below or above the water. There is some recent precedent for such a fire; last year in the Gulf of Mexico, a leaking gas pipeline sparked into flame and opened what some described as “the gates of hell.” Those gates were soon closed; authorities shut off valves in the pipeline, and firefighting boats on the surface helped extinguish the flames after five hours.


How damaging is this environmentally?

While a sabotaged underwater pipeline may conjure images of the 2010 Deepwater Horizon oil spill or even the 1989 Exxon Valdez disaster, the situation with the Nord Stream pipelines is very different and less locally damaging. The pipelines contain natural gas rather than crude oil; the gas will rise quickly through the water column and escape into the atmosphere, as video and images of a frothing circle over the leak have demonstrated.

Still, leaking natural gas is not without impact. Most of the gas is composed of methane, a greenhouse gas that is far more powerful in terms of warming the planet than carbon dioxide. And 300 million cubic meters is not an insignificant amount — according to one estimate, the release of the Nord Stream gas would be equivalent to around 200,000 tons of methane. A representative of the satellite monitoring firm GHGSat, which tracks methane emissions, told Reuters the leak was progressing at around 500 metric tons every hour. It is possible that some of the methane would be transformed by microbes in the water into carbon dioxide, meaning the climate impact would be lower, but the water may be too shallow and the release too abrupt and fast for that to occur, experts have said.

Though there is still uncertainty over the exact amounts and whether there are other more localized ecological impacts, overall this would likely represent a relatively small portion of the globe’s annual methane missions — which run as high as 500 million tons each year.

How do you fix something like this?

Fixing underwater pipelines and other oil and gas infrastructure can be extremely problematic. Exhibit A for this is the Deepwater Horizon catastrophe, when the leaking well spawned numerous technical ideas for solutions, but eventually took months to actually cap the oil. Again, the Nord Stream pipelines are very different: They lie in much shallower water (around 80 to 110 meters, or around 260 to 360 feet, compared with almost a mile below the surface for Deepwater), and there is a finite amount of gas inside them rather than an effectively endless supply of oil shooting up from a well.

If the claims of sabotage and explosions are correct, there likely isn’t a quick fix for what might be significant holes in the pipelines. With the lines currently shut off and not receiving more gas, that would mean that simply letting all the gas leak out would be the likely end of the acute disaster; beyond that, the timeline for a fix is unclear. According to the Nord Stream company itself: “Currently, it is not possible to estimate a timeframe for restoring the gas transport infrastructure.”

Who could be behind this?

Europe’s assessment that the damage to the pipelines was “deliberate” inevitably begs the question: Who did this?

This is perhaps the most difficult question to answer — the question with the spy-novel qualities. That doesn’t mean a lot of people are shying from giving their answers.

Given the Kremlin’s actions over the past year, many were quick to point the finger at Russia. Could this, many wondered, be a new chapter in the energy war that is already roiling the European continent? After shutting off gas supplies via the Nord Stream 1 pipeline, was Russian President Vladimir Putin raising the stakes even higher by damaging both of these critical energy supply lines?

Several leaders went beyond wondering. A senior adviser to Ukrainian President Volodymyr Zelenskyy tweeted that the blasts were nothing more than “a terrorist attack planned by Russia and an act of aggression towards [the] EU.” Poland’s Prime Minister Mateusz Morawiecki said the blast was “related to the next step of escalation of the situation in Ukraine.”

The Kremlin’s answer was an emphatic no. Putin’s chief spokesman Dmitry Peskov used a Wednesday conference call with reporters to hit back at the speculation, saying that suggestions that Russia was behind the underwater blasts was “predictable and also predictably stupid.” Peskov added that “this is a big problem for us … the entire system is ready to pump gas and the gas is very expensive. Now the gas is flying off into the air.”


The fallout, Peskov argued, didn’t just affect Europe — but also Russia, which relies on the pipelines to earn critical energy dollars. “Are we interested in that? No, we are not, we have lost a route for gas supplies to Europe,” Peskov said.

Indeed, as Richard Morningstar, former U.S. ambassador to the European Union and founding chairman of the Atlantic Council’s Global Energy Center, told Grid, “it is a strange situation.” For Russia, he explained, “it doesn’t make sense to damage the pipelines.”

But if not Russia, then who — and why?

There is no straightforward list of suspects. Some pointed fingers — with no evidence — at Western Europeans seeking to put the final nail in the coffin of any dependence on Russian energy. Others suggested that nonstate saboteurs might have been involved.

Russian state media, meanwhile, was predictably quick to pick up on a tweet by a former Polish foreign minster, Radek Sikorski, who tweeted a picture of the surface waters around the damaged pipelines with the caption: “Thank you, USA.” The suggestion: that the damage was done to inflict pain on Russia by cutting off a source of energy dollars for the country.


For his part, Secretary of State Antony Blinken said that the leaks were “clearly in no one’s interest.”

Certainly it’s not in Western Europe’s interest. This was made clear by movements on the financial markets on Tuesday, as traders factored in the damage and its potential impact on future supplies. Already sky-high European gas prices rose by around 19 percent. From the point of view of the financial markets, the damage meant that investors were revising expectations of when supplies might resume via the Nord Stream 1 pipeline. What had been a timeline based on the war now must factor in the questions of repair. As one Market analyst told the Financial Times: “The probability of Nord Stream 1 coming back before the end of the year has essentially dropped from 1 per cent to zero per cent.”

Thanks to Lillian Barkley for copy editing this article.

  • Dave Levitan
    Dave Levitan

    Climate Reporter

    Dave Levitan is a climate reporter for Grid where he focuses on interconnected stories about climate and science, and politics shaping action around both.

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    Nikhil Kumar

    Deputy Global Editor

    Nikhil Kumar is the deputy global editor at Grid, reporting on global affairs.

  • Joshua Keating
    Joshua Keating

    Global Security Reporter

    Joshua Keating is a global security reporter for Grid focused on conflict, diplomacy and foreign policy.