The Alaska Pipeline next to the Dalton Highway in Alaska

The Trans-Alaska Pipeline System (TAPS) includes the trans-Alaska crude-oilpipeline, 11 pump stations, several hundred miles of feeder pipelines, and the Valdez Marine Terminal. TAPS is one of the world’s largest pipeline systems. It is commonly called the Alaska pipelinetrans-Alaska pipeline, or Alyeska pipeline, but those terms technically apply only to the 800 miles (1,287 km) of the pipeline with the diameter of 48 inches (1.22 m) that conveys oil from Prudhoe Bay to Valdez, Alaska.

In building the pipeline, engineers faced a wide range of difficulties, stemming mainly from the extreme cold and the difficult, isolated terrain. The construction of the pipeline was one of the first large-scale projects to deal with problems caused by permafrost, and special construction techniques had to be developed to cope with the frozen ground. The project attracted tens of thousands of workers to Alaska, causing a boomtown atmosphere in Valdez, Fairbanks, and Anchorage.

Although the legal right-of-way was cleared by January 1974, cold weather, the need to hire workers, and construction of the Dalton Highway meant work on the pipeline itself did not begin until March. Between 1974 and July 28, 1977, when the first barrel of oil reached Valdez, tens of thousands of people worked on the pipeline. Thousands of workers came to Alaska, attracted by the prospect of high-paying jobs at a time when most of the rest of the United States was undergoing a recession.

Construction workers endured long hours, cold temperatures, and brutal conditions. Difficult terrain, particularly in Atigun Pass, Keystone Canyon, and near the Sagavanirktok River forced workers to come up with solutions for unforeseen problems. Faulty welds and accusations of poor quality control caused a Congressional investigation that ultimately revealed little. More than $8 billion was spent to build the 800 miles (1,300 km) of pipeline, the Valdez Marine Terminal, and 12 pump stations. The construction effort also had a human toll. Thirty-two Alyeska and contract employees died from causes directly related to construction. That figure does not include common carrier casualties

The pipeline is surveyed several times per day, mostly by air. Foot and road patrols also take place to check for problems such as leaks or pipe settling or shifting. The pipeline can be surveyed in as little as twenty one days, but most surveys take longer to ensure thoroughness. These external inspections are only part of standard maintenance, however. The majority of pipeline maintenance is done by pipeline pigs—mechanical devices sent through the pipeline to perform a variety of functions.

Trans-Alaska Pipeline System
The trans-Alaska oil pipeline,
as it zig-zags across the landscape
Location of trans-Alaska pipeline
CountryAlaska, United States
Coordinates70°15′26″N148°37′8″WCoordinates70°15′26″N 148°37′8″W
General directionNorth-South
FromPrudhoe Bay, Alaska
ToValdez, Alaska
Runs alongsideDalton Highway
Richardson Highway
Elliott Highway
General information
TypePump stations
OwnerAlyeska Pipeline Service Company
Exxon Mobil
Koch Industries
Chevron Corporation
Commissioned1977; 42 years ago[
Technical information
Length800.3 mi (1,288.0 km)
Maximum discharge2.136 MMbbl/d (339,600 m3/d)
Diameter48 in (1,219 mm)
No. of pumping stations