Crude crossing: planned Cook Inlet subsea pipeline could eliminate risky oil tanker runs.

• Author: Loy, Wesley
• Position: SPECIAL SECTION: Building Alaska

One of Alaska's biggest planned construction projects in 2014 will be largely out of sight. That's because it'll be on the bottom of turbulent Cook Inlet.

The project is called the Trans-Foreland Pipeline. It's a subsea pipeline to carry crude oil produced on the remote west side of the inlet to Tesoro's Nikiski refinery on the east side.

It's an ambitious and costly project. The main backer, Tesoro, has told regulators the cost of the cross-inlet pipeline, including materials and installation, totals $50 million.

As the magazine went to press, Tesoro was pursuing a number of government authorizations for building the pipeline. One of these was a right of way from the Department of Natural Resources to lay the pipe across state submerged lands.

Why Build It?

Several factors play into the decision to build the pipeline. They can be summed up with three words: safety, reliability, and cost.

Pipeline backers believe a subsea pipeline would be a safer means of moving oil across the inlet. The job currently is done with tankers that fill up at the Drift River oil terminal on the west side and then sail to the refinery on the east.

Oil tankers always carry the risk of catastrophic spills, and this concern is heightened in Cook Inlet because of the prevalence of ice in wintertime. The drifting ice, coupled with the inlet's extreme tides, can be extremely powerful. It has even been known to rip ships from their moorings.

The Trans-Foreland Pipeline could also make oil transportation across the inlet more reliable.

Westside crude currently feeds through an onshore pipeline system to the Drift River terminal, which includes a tank farm and the Christy Lee offshore platform where ships dock to take on oil.

The terminal has worked since it was built in the 1960s, but a big threat looms nearby: Mount Redoubt, an active volcano.

In March 2009, Redoubt erupted, sending mud flows known as lahars down the Drift River. Protective berms built around the terminal saved it from a potentially disastrous inundation. But the event forced a terminal shutdown, idling west inlet oil production for months.

To restore oil shipments, operators resorted to piping crude from producers directly onto tankers, bypassing the tank farm. The Drift River terminal owner, Hilcorp, has since resumed partial use of the tank farm after beefing up flood fortifications.

Going forward, proponents see the new subsea pipeline as a more reliable oil transportation option than the tanker...