Construction of the Trans-Alaska Pipeline System

The construction of the Trans-Alaska Pipeline System included over 800 miles (1,300 km) of oil pipeline, 12 pump stations, and a new tanker port. Built largely on permafrost during 1975–77 between Prudhoe Bay and Valdez, Alaska, the $8 billion effort required tens of thousands of people, often working in extreme temperatures and conditions; the invention of specialized construction techniques; and the construction of a new road, the Dalton Highway.

The first section of pipe was laid in 1975 after more than five years of legal and political arguments. Allegations of faulty welds drew intense scrutiny from local and national observers. A culture grew around the unique working conditions involved in constructing the pipeline, and each union that worked on the project had a different function and stereotype. Thirty-two Alyeska Pipeline Service Company employees and contract workers were killed during the project. The main construction effort lasted until 1977; the first barrel of oil was delivered on July 28 of that year. Several more pump stations, added as oil flow increased, were completed through 1980.

Intensive geological sampling and survey work of the pipeline route started in spring 1970. Aerial photograph were taken, examined, and a preliminary route was detailed. Small survey parties physically visited the route and hammered stakes into the ground. The work was difficult; animal dangers forced the crews to be armed, and they also had to cope with the remote area and limited infrastructure. In places, the foliage was so dense that trees had to be cut down and progress was limited to 20,000 feet (6.1 km) per day. The surveyed route passed through several mountain passes: Atigun Pass, Isabel Pass, Thompson Pass, and Keystone Canyon. In the latter location, surveyors had to rappel down cliffs in order to perform their work.

Surveyors and planners also had to deal with the Denali Fault, a major cause of earthquakes, and with large amounts of permafrost. In 1969, the unincorporated Trans-Alaska Pipeline System group drilled a series of core samples north of the Brooks Range that demonstrated how ubiquitous the permafrost was along the route. This forced the design of an elevated pipeline, which was tested in a 1,000 feet (300 m) loop built near Barrow. This elevation required the pipeline to be insulated, since extreme cold temperatures caused the metal to become brittle, even when hot oil was being pumped through the pipeline.

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