Climate change activists shut off cross-border oil pipelines in Minnesota, Montana, North Dakota, and Washington on Tuesday. The activists broke in to unguarded valve stations and shut off the flow of oil before being arrested. Reuters reports:

All they had to do was twist shut giant valves on five cross-border pipelines that together can send 2.8 million barrels a day of crude to the United States from Canada – equal to about 15 percent of daily U.S. consumption.

The pipelines have valve stations every 20 miles, many of them in remote locations and protected by nothing more than a locked fence. Reuters quotes a Canadian pipeline security specialist who says, given that there are 200,000 miles of pipelines in the U.S., it would be cost prohibitive to place round-the-clock guards at all of the possible places where a pipeline could be shut off.

None of the pipelines involved were damaged and all of them were back up and running Wednesday. However, experts Reuters spoke with say this stunt could have gone very wrong:

Protesters said they spent months studying how to safely shut the valves. The ability for them to access the proprietary information necessary to shut a line safely was questioned by experts.

Either way, pipeline specialists said it was lucky there were no leaks on Tuesday. Once the valves are shut, pressure can quickly build up inside pipelines that operate under as much as 1,000 pounds (450 kg) per square inch.

Protesters were taking a chance that a weak spot in a line would not explode, and that employees in operations hubs would spring into action after hearing alarms.

“On the wrong pipeline, in the wrong place (actions like this) could kill people. This is hazardous hot liquid. It’s not something to be terrified of, but it must be respected,” said Richard Kuprewicz, president of Accufacts Inc, a pipeline advisory firm.

Needless to say, this is not protest activity it is criminal activity. According to the Duluth News, activists waited to be arrested after shutting off the valves:

The activists used bolt cutters to gain access to the locked stations and then remained at the valve stations to be arrested after sticking symbolic flowers into valves, said Afrin Sopariwala, a spokeswoman for the group.

“They did the research to make sure this wouldn’t cause any environmental harm. They used the emergency valves because this is a climate emergency,” she said.

Sopariwala said the activists involved have spent several years signing petitions, talking to political representatives and pursuing other legal avenues to fight climate change, but said the efforts hadn’t made a difference.

“We felt compelled to take an escalated action,” she said.

Since there doesn’t seem to be any question of guilt in this case, hopefully the activists will spend some time in jail. Climate Direct Action, the group which sponsored and promoted this, is now raising funds for the legal defense of the activists.