Pipeline 101

How often is pigging performed? 

Alyeska currently runs a cleaning pig through the 48” mainline pipeline every 4-7 days to remove wax deposits and water. Inline inspection (ILI) tools — or smart pigs — are run every three years to inspect the condition of the pipe. The latest smart pig inspection which was performed in October used a combination tool to inspect for corrosion, deformation, and curvature rather than having to run two separate tools as in the past. Timely inspection allows Alyeska to analyze and trend anomalies in the pipe in order to make necessary repairs before they affect the pipe integrity. In over 30 years of operation, 62 smart pig inspections have been performed — and there has never been a leak on the mainline pipe due to corrosion during this time.