Minnesota has a pipeline problem. Specifically, the Enbridge Line 3 pipeline that carries tar sands crude oil from Canada, through this state to its destination in Superior, Wis.

Built in 1968, the pipeline is a relic — aging and corroded to the point that it operates at half-capacity to avoid the pressure that at full volume might trigger leaks. If that sounds dangerous, it is. Enbridge wants to replace the pipe and add capacity, a $2 billion undertaking that also would route the new 330-mile line away from the Leech Lake tribal reservation.

But replacement of the pipe has become entangled in a bureaucratic, environmental quagmire that now has delayed the project a full year and sparked a battle in which Gov. Tim Walz allowed his Commerce Department to continue to challenge the Public Utilities Commission on its unanimous decision to issue a certificate of need. Shortly after, Enbridge announced the delay.

That means another year of risk to the communities whose property the old line runs through. Worse still, even higher rail shipments of oil. Without additional pipeline capacity, such shipments have hit historic highs. That oil travels through some of the most densely populated areas of the state, posing a potential environmental disaster should there be a derailment.

To some it's obvious the line should be replaced without delay. Others are equally adamant that the replacement will wed the state even further to fossil fuels just as it is trying to move toward clean energy. And while the new line would not run on reservation land, it would still run through treaty lands, which has prompted strong protest from tribes intent on protecting the quality of those lands.

There are no easy answers here. The Star Tribune Editorial Board remains committed to environmental quality and clean energy goals. And it does not take lightly the protests of tribes that have suffered repeated treaty violations in the past.

But the uncomfortable fact remains that failing to replace the pipeline will not eliminate risk, it will enhance it. And while Minnesota has no oil reserves of its own, it plays a far larger role in oil distribution than many would assume. According to Minnesota House research, 30 percent of all crude oil in the U.S. comes through Minnesota — more than 800 million barrels in 2015.

What doesn't come through the state's half-dozen pipelines typically is shipped by rail. Minnesota serves as the primary route from Canada, supplier of more than 40 percent of foreign oil imports. Minnesota also is home to two major refineries and 15 petroleum storage terminals. All of which is to say that Minnesota's problem in separating itself from fossil fuels is far larger than Line 3, and will take decades to accomplish.

That separation must occur, for the good of the environment. But in the meantime, Minnesota must take responsibility for its energy needs. A new Line 3 should be seen as a transition that will take more oil off rail cars while the state and nation wean themselves off fossil-fuel sources. Unless Minnesota is prepared to try to block rail shipments of oil, it is difficult to see what is accomplished by defaulting to a more dangerous mode of transport.

It is disappointing that Walz allowed the Commerce Department to challenge the PUC. The commission's process was rigorous and exhaustive. The commissioners, all appointed by former Gov. Mark Dayton, agonized over their decision but concluded that the safety risk posed by the existing line left no viable alternative. "It's a question of safety," Commissioner Katie Sieben said.

Walz has said he wants to give tribes a greater say and honor their sovereignty. But in this case, blocking the replacement line will leave a corroding and cracking pipeline running across the Leech Lake reservation.

Walz and the Commerce Department should drop the court challenge and allow the project to proceed.