Shell’s drill ships left Seattle Wednesday morning, headed for Unalaska on their way to the Arctic. The ships were originally scheduled to bypass town, but now it looks like they might be around for a while.

Persistent sea ice in the Alaskan Arctic could delay the start of the drilling season by two to three weeks, according to Shell Alaska spokesperson Curtis Smith. The company had hoped to start work in the Chukchi and Beaufort Seas on July 15.

National Weather Service ice forecaster Kathleen Cole says ice retreat in the Chukchi Sea is at least three weeks behind normal. Cole adds that while ice is leaving the Beaufort Sea more quickly, there’s plenty of ice between the Aleutians and there. Shell has said it won't break its way through ice to get to the drill sites. 

The delayed start will definitely cut into Shell’s already short drilling season. The company has to be out of the Chukchi by the end of September and out of the Beaufort by the end of October. The ice delays are compounded by the fact that Shell has also agreed to suspend operations for several weeks in late August, during the annual bowhead whale hunt.

The Department of the Interior still hasn't issued the final drill permits that Shell needs before it can head north. Those are contingent on a successful test of the company's oil spill containment system, which is scheduled for sometime in the next few weeks.