The Trans-Alaska Pipeline System (TAPS) is an oil transportation system spanning Alaska, including the trans-Alaska crude-oil pipeline, 12 pump stations, several hundred miles of feeder pipelines, and the Valdez Marine Terminal. TAPS is one of the world's largest pipeline systems. The core pipeline itself, which is commonly called the Alaska pipeline, trans-Alaska pipeline, or Alyeska pipeline, (or the pipeline as referred to by Alaskan residents), is an long, diameter pipeline that conveys oil from Prudhoe Bay, on Alaska's North Slope, south to Valdez, on the shores of Prince William Sound in southcentral Alaska. The crude oil pipeline is privately owned by the Alyeska Pipeline Service Company.
Oil was first discovered in Prudhoe Bay in 1968 and the 800 miles of 48" steel pipe was ordered from Japan in 1969 (U.S. steel manufacturers did not have the capacity at that time). However, construction was delayed for nearly 5 years due to legal and environmental issues. The eight oil companies that owned the rights to the oil hired Bechtel for the pipeline design and construction and Fluor for the 12 pump stations and the Valdez Terminal. Preconstruction work during 1973 and 1974 was critical and included the building of camps to house workers, construction of roads and bridges where none existed, and carefully laying out the pipeline right of way to avoid difficult river crossings and animal habitats. Construction of the pipeline system took place between 1975 and 1977. It was important for the United States to have a domestic source of oil to offset the high rise in foreign oil and the Alaska Pipeline fulfilled that obligation.
Building oil pipelines in the 1950s and 60s was not difficult in the contiguous United States. However, in building the Alaska 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 due to high wages, long work hours, and paid-for housing, causing a boomtown atmosphere in Valdez, Fairbanks, and Anchorage.
The first barrel of oil traveled through the pipeline in the summer with full-scale production by the end of the year. Several notable incidents of oil leakage have occurred since, including those caused by sabotage, maintenance failures, and bullet holes. As of 2026, it had shipped over 19 billion barrels of oil. The pipeline has been shown capable of delivering over 2 million barrels of oil per day but currently operates at a fraction of maximum capacity, around 470,000 barrels per day. If flow were to stop or throughput were too little, the line could freeze. The pipeline could be extended and used to transport oil produced from controversial proposed drilling projects in the nearby Arctic National Wildlife Refuge (ANWR).
Origins
Iñupiat people on the North Slope of Alaska had mined oil-saturated peat for possibly thousands of years, using it as fuel for heat and light. Whalers who stayed at Point Barrow saw the substance the Iñupiat called pitch and recognized it as petroleum. Charles Brower, a whaler who settled at Barrow and operated trading posts along the Arctic coast, directed geologist Alfred Hulse Brooks to oil seepages at Cape Simpson and Fish Creek in the far north of Alaska, east of the village of Barrow.Banet, p. 27 Brooks' report confirmed the observations of Thomas Simpson, an officer of the Hudson's Bay Company who first observed the seepages in 1836.Naske p. 241 Similar seepages were found at the Canning River in 1919 by Ernest de Koven Leffingwell.Leffingwell, E.d. "The Canning River region, northern Alaska: U.S. Geological Survey Professional Paper 109", U.S. Geological Surveye. 1919. Accessed June 14, 2009. Following the First World War, as the United States Navy converted its ships from coal to fuel oil, a stable supply of oil became important to the U.S. government. Accordingly, President Warren G. Harding established by executive order a series of Naval Petroleum Reserves (NPR-1 through -4) across the United States. These reserves were areas thought to be rich in oil and set aside for future drilling by the U.S. Navy. Naval Petroleum Reserve No. 4 was sited in Alaska's far north, just south of Barrow, and encompassed .Bird, Kenneth J. and Houseknecht, David W. "2002 Petroleum Resource Assessment of the National Petroleum Reserve in Alaska (NPRA)", USGS. 2002. Accessed June 14, 2009.
The first explorations of NPR-4 were undertaken by the U.S. Geological Survey from 1923 to 1925 and focused on mapping, identifying and characterizing coal resources in the western portion of the reserve and petroleum exploration in the eastern and northern portions of the reserve. These surveys were primarily pedestrian in nature; no drilling or remote sensing techniques were available at the time. These surveys named many of the geographic features of the areas explored, including the Philip Smith Mountains and quadrangle.Smith and Mertie 1930
The petroleum reserve lay dormant until World War II provided an impetus to explore new oil prospects. The first renewed efforts to identify strategic oil assets were a two pronged survey using bush aircraft, local Inupiat guides, and personnel from multiple agencies to locate reported seeps. Ebbley and Joesting reported on these initial forays in 1943. Starting in 1944, the U.S. Navy funded oil exploration near Umiat Mountain, on the Colville River in the foothills of the Brooks Range.Naske, p. 244 Surveyors from the U.S. Geological Survey spread across the petroleum reserve and worked to determine its extent until 1953, when the Navy suspended funding for the project. The USGS found several oil fields, most notably the Alpine and Umiat Oil Field, but none were cost-effective to develop.Naske, pp. 245–246
Four years after the Navy suspended its survey, Richfield Oil Corporation (later Atlantic Richfield and ARCO) drilled an enormously successful oil well near the Swanson River in southern Alaska, near Kenai.Naske, p. 247 The resulting Swanson River Oil Field was Alaska's first major commercially producing oil field, and it spurred the exploration and development of many others.Roscow, p.53 By 1965, five oil and 11 natural gas fields had been developed. This success and the previous Navy exploration of its petroleum reserve led petroleum engineers to the conclusion that the area of Alaska north of the Brooks Range surely held large amounts of oil and gas.Roscow, p. 27 The problems came from the area's remoteness and harsh climate. It was estimated that between and of oil would have to be recovered to make a North Slope oil field commercially viable.
In 1967, Atlantic Richfield (ARCO) began detailed survey work in the Prudhoe Bay area. By January 1968, reports began circulating that natural gas had been discovered by a discovery well.Roscow, p. 10 On March 12, 1968, an Atlantic Richfield drilling crew hit paydirt."Prudhoe Bay Fact Sheet" (PDF), BP. Accessed July 15, 2009. A discovery well began flowing at the rate of of oil per day. On June 25, ARCO announced that a second discovery well likewise was producing oil at a similar rate. Together, the two wells confirmed the existence of the Prudhoe Bay Oil Field. The new field contained more than of oil, making it the largest in North America and the 18th largest in the world.
The problem soon became how to develop the oil field and ship product to U.S. markets. Pipeline systems represent a high initial cost but lower operating costs, but no pipeline of the necessary length had yet been constructed. Several other solutions were offered. Boeing proposed a series of gigantic 12-engine tanker aircraft to transport oil from the field, the Boeing RC-1.Naske, p. 256 General Dynamics proposed a line of tanker submarines for travel beneath the Arctic ice cap, and another group proposed extending the Alaska Railroad to Prudhoe Bay.Naske, pp. 256–257
To test this, in 1969 Humble Oil and Refining Company sent a specially fitted oil tanker, the , to test the feasibility of transporting oil via ice-breaking tankers to market.Gedney, Larry and Helfferich, Merritt. "Voyage of the Manhattan" , Alaska Science Forum. December 19, 1983. Accessed June 14, 2009. The Manhattan was fitted with an ice-breaking bow, powerful engines, and hardened propellers before successfully traveling the Northwest Passage from the Atlantic Ocean to the Beaufort Sea. During the voyage, the ship suffered damage to several of its cargo holds, which flooded with seawater. Wind-blown ice forced the Manhattan to change its intended route from the M'Clure Strait to the smaller Prince of Wales Strait. It was escorted back through the Northwest Passage by a Canadian Coast Guard icebreaker, the CCGS John A. Macdonald. Although the Manhattan transited the Northwest Passage again in the summer of 1970, the concept was considered too risky.Kavanagh, Dave. "S.S. Manhattan & the Northwest Passage", sunshiporg.homestead.com. July 12, 2005. Accessed June 14, 2009.
Forming Alyeska
In February 1969, before the SS Manhattan had even sailed from its East Coast starting point, the Trans-Alaska Pipeline System (TAPS), an unincorporated joint group created by ARCO, British Petroleum, and Humble Oil in October 1968,Roscow, p. 17 asked for permission from the United States Department of the Interior to begin geological and engineering studies of a proposed oil pipeline route from Prudhoe Bay to Valdez, across Alaska. Even before the first feasibility studies began, the oil companies had chosen the approximate route of the pipeline.Naske, p. 252
Because TAPS hoped to begin laying pipe by September 1969, substantial orders were placed for steel pipeline 48 inches (122 cm) in diameter.Facts, p. 43 No American company manufactured pipe of that specification, so three Japanese companies—Sumitomo Metal Industries, Nippon Steel Corporation and Nippon Kokan Kabushiki Kaisha—received a $100 million contract for more than 800 miles (1280 km) of pipeline. At the same time, TAPS placed a $30 million order for the first of the enormous pumps that would be needed to push the oil through the pipeline.Mead, p. 118
In June 1969, as the SS Manhattan traveled through the Northwest Passage, TAPS formally applied to the Interior Department for a permit to build an oil pipeline across of public land—from Prudhoe Bay to Valdez.Naske, p. 251 The application was for a 100-foot (30.5 m) wide right of way to build a subterranean 48-inch (122-centimeter) pipeline including 11 pumping stations. Another right of way was requested to build a construction and maintenance highway paralleling the pipeline. A document of just 20 pages contained all of the information TAPS had collected about the route up to that stage in its surveying.Berry, p. 106
The Interior Department responded by sending personnel to analyze the proposed route and plan. Max Brewer, an arctic expert in charge of the Naval Arctic Research Laboratory at Barrow, concluded that the plan to bury most of the pipeline was completely unfeasible because of the abundance of permafrost along the route. In a report, Brewer said the hot oil conveyed by the pipeline would melt the underlying permafrost, causing the pipeline to fail as its support turned to mud. This report was passed along to the appropriate committees of the U.S. House and Senate, which had to approve the right-of-way proposal because it asked for more land than authorized in the Mineral Leasing Act of 1920 and because it would break a development freeze imposed in 1966 by former Secretary of the Interior Stewart Udall.Naske, p. 253