The Minnesota Public Utilities Commission called on pipeline builder Enbridge Energy to examine new routes for its planned Sandpiper oil project.

Sandpiper would stretch 616 miles from Tioga, N.D., through Minnesota and to an Enbridge terminal in Superior, Wisc. It would then transfer oil to other pipelines for delivery to the U.S. and Canadian refinery markets.

State regulators in a 3-2 decision called on Enbridge to study the environmental issues surrounding six alternative routes through the state proposed by outside groups.

State Commissioner Dan Lipschultz said Minnesota regulators need to take their time in approving a pipeline designed to carry crude oil from the Bakken reserve area in North Dakota.

"I don't want to rush to a thumbs down any more than I want to rush to a thumbs up," he said Thursday. "I want to get it right."

Enbridge in June received backing from state legislators in North Dakota to build Sandpiper. Enbridge attorney Christina Brusven said each setback is a setback in terms of the pipeline's economic benefits.

Enbridge said it wants to have Sandpiper in service by 2016.