MINNEAPOLIS (WCCO) — Many riders who depend on the Northstar Commuter Rail are frustrated.

In four of the past five weekdays, some routes have had delays of 20 minutes or more, causing many passengers to arrive late to work or school.

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“We had to wait for some freight trains to pass,” said James Weber of Anoka, “so I was about 10, 15 minutes late.”

“My boss is very understanding,” said Cindy Gagnier of Big Lake, “but I know a lot of people have had a lot of difficulty with their employers.”

Ted Peterson of Andover gave up waiting in the cold on Tuesday.

“It’s been late for the past few days,” he said, “and yesterday I had to drive.”

It highlights one of the weaknesses of the Northstar system.

The tracks are not owned by Metro Transit. They’re owned by BNSF, and used 90 percent of the time for freight.

Metro Transit spokesperson Drew Kerr said Northstar trains don’t have much chance to pass if another train is blocking the track.

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“So as freight rail traffic is disrupted that affects Northstar,” he said. “We’ve got trains that are backed up, we need to get around. These are the kind of issues that we’re dealing with.”

Kerr blames weather, in part, for issues this week. There have been broken tracks and frozen switchers.

“This is certainly an anomaly,” he said. “I think for the majority of our customers who are using Northstar every day, they know their train is going to be there on time and they’re going to get to work on time as well.”

Metro Transit’s agreement with BNSF spells out how things are supposed to work. The freight traffic is supposed to be synchronized during the morning and evening commutes, so as not to disrupt the Northstar trains.

But sometimes, as we’re seeing lately, the unexpected happens.

One passenger, Judi Skappel of Becker, said she simply leaves early and builds in extra time.

“Well, I usually have something to read,” she said. “A lot of people have laptops, just keep ourselves occupied.”

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Some people complained about a lack of notice, as they’re waiting outside. Metro Transit does send out tweets and Facebook posts when there’s a delay, but they’re looking into other ways to send more direct messages.