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The Trans-Alaska Pipeline

Construction of the mighty 800-mile Trans-Alaska Pipeline began after the discovery of the largest oil field in 1968, underneath Prudhoe Bay in the United States.

The finding on Alaska’s North Slope prompted the creation of an efficient and safe way to transport the oil into the marketplace. Today, the pipeline has been recognised as a landmark of engineering, costing $8 billion to build and carrying an average of around 1.8 million barrels of oil each day.


How it began

Three companies – British Petroleum, Atlantic Richfield Company and Exxon Corporation subsidiary Humble Oil – joined forces and reached an agreement to build the pipeline.

The aim was to connect the North Slope to the port of Valdez, on Prince William Sound, at the Gulf of Alaska. The pipe has a diameter of 48 inches and features pumping stations at intervals along its length to keep the flow of oil constant at around 4mph.

Plans for the pipeline were presented to the US Senate, but before the scheme was eventually approved, years of debate ensued about the possible environmental repercussions. These included concerns about earthquakes, the impact on the elk population and the effects on the native Americans’ way of life.


Legal battle

A long legal battle ensued after the Tlingit population – who claimed the land was theirs – set up an organisation called the Alaska Federation of Natives to fight the pipeline plans.

This resulted in an agreement being reached in October 1971 by President Richard Nixon, who signed the Alaska Native Claims Settlement Act. This meant the native groups renounced their claims to the land in return for $962.5 million compensation and 148.5 million acres of federal land.

The land and money were divided between regional corporations and villages, so that every person received their share.

After years of debate and legal arguments, the Trans-Alaska Pipeline Authorisation Act was finally passed. Vice President Spiro Agnew used his deciding vote to pass the legislation on 17th July 1973, after the senators’ vote was tied 49-49.



The first section of pipe was laid on 27th March 1975, officially launching the largest private construction project in American history at the time.

During the construction process, ongoing changes were made in the pipeline’s design, due to the complexity of the project and the challenges raised by its completion. This caused the initial estimated cost of $900 million in 1969 to increase to $4 billion by 1973. The final cost was $8 billion and on top of that, construction of the Valdez Marine Terminal cost a further $1.4 billion.

The pipeline was constructed by the Alyeska Pipeline Service Company. It was buried underground in some areas, but was built above ground in other areas where there was permafrost. It was also built in a zigzag manner, so it would be flexible and therefore safer should there be an earthquake.

Around 20,000 workers laboured seven days a week and 12 hours a day to finish the pipeline on time. A 360-mile long road was built first to access the 30 construction camps.

Over the 800-mile length of the pipe, it passes across three mountain ranges and more than 800 river and stream crossings. The original design was modified to allow caribou to march underneath as they migrated.

The pipeline took a relatively short time to construct, in spite of its complexity. It was completed on 31st May 1977 and the first oil left Prudhoe Bay on 20th June 1977. It took around nine days to reach Valdez.

Full-scale production had begun by the end of 1977 and the Trans-Alaska Pipeline moved its billionth barrel of oil in 1980.


Oil spill

The project wasn’t without its difficulties. In fact, it was the scene of the second largest oil spill in the USA’s history on 24th March 1989. The environmental disaster occurred when an oil tanker, Exxon Valdez, owned by Exxon Shipping Company, struck Prince William Sound’s Bligh Reef en route to Long Beach, California.

It spilled 10.8 million US gallons of crude oil over a period of several days. The oil spread over an area covering 11,000 square miles of ocean and 1,300 miles of coastline. Animals and marine life were severely affected by the spill, including all of those living at Prince William Sound, such as sea otters, salmon, seals and many seabirds.

The area where most environmental damage was sustained wasn’t easily accessible and the clean-up operation took much longer than anticipated. Exxon reportedly spent $2 billion cleaning up and had to pay out a further $1 billion as a result of civil and criminal charges.


Causes of the accident

Several reasons were cited for the disastrous oil spill. The National Transportation Safety Board ruled that Exxon Shipping Company had failed to properly supervise the ship’s master and provide sufficient and rested crew members. This led to revised safety recommendations industry-wide.

It was said the third mate had failed to properly manoeuvre the tanker – possibly due to excessive workload and fatigue – and that Exxon Shipping Company had not properly maintained the Raytheon Collision Avoidance System. Had the radar been functional, it would have warned the crew of the impending collision with Bligh Reef.



By 1991, the local marine population, including seals, herring and clams, had collapsed as a result of the oil spill. The Chugach Alaska Corporation, an Alaskan native organisation, filed for bankruptcy protection, but later went on to recover.

The spill had short and long-term economic effects, including a loss of fisheries, recreational sports, tourism and quality of life. At the time of the spill, the village of Chenega became an emergency base and media centre and the population tripled. Local people were left feeling shocked as everyone began pitching in to help with the clean-up operation.

Today, almost three decades later, as a result of the oil spill, most tankers now have double hulls, so that if they strike anything, it will never completely rupture. Federal agencies have also made their response times quicker.

Pipecraft Innovations is a leading UK precision engineering company, offering practical solutions to several sectors, including engineering, design and manufacturing. Established in 1980, we specialise in tube manipulation and the production of any form of tubular-based product. Please contact us for further information about our products and services.

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