What Is the Keystone Pipeline?

How a single pipeline project became the epicenter of an enormous environmental battle.
Pipeline under construction in Alberta, Canada


If ever there was an environmental battle exemplifying a game of ping pong, it would be the stop-start story of the Keystone XL pipeline, also known as KXL. From the time it was proposed in 2008, through seven years of dogged citizen protest and various conflicting legislative orders by the federal government, the path for this controversial oil pipeline has never been smooth. In the most recent chapter of the fight, President Obama vetoed the pipeline in November 2015—acknowledging its pervasive threats to ecosystems, drinking water sources, and public health; and advancing a national commitment to decreasing our reliance on dirty energy. Then, immediately after taking office, President Trump reversed course on Obama’s pledge. In January, he signed an executive order to advance Keystone XL (as well as the Dakota Access Pipeline), and in March, the U.S. State Department issued the pipeline developers their long-sought cross-border permit, reversing course on the department’s own previous decision, claiming the project would now “support U.S. priorities relating to energy security, economic development, and infrastructure.” Here’s an overview of the export tar sands pipeline that’s become one of the foremost climate controversies of our time. 

What is Keystone XL?

The Keystone XL pipeline extension, proposed by energy infrastructure company TransCanada in 2008, was designed to transport the planet’s dirtiest fossil fuel to market, fast. An expansion of the company’s existing Keystone Pipeline System, operating since 2008 (and already sending Canadian crude from Alberta to various processing hubs in the middle of the United States), it would dramatically increase capacity to process the 168 billion barrels of crude oil locked up in Canada’s boreal forest. To be precise, it would transport 830,000 barrels of Alberta tar sands oil per day to refineries on the Gulf Coast of Texas.

Some 2.6 million miles of oil and gas pipelines already run through our country. But Keystone XL wouldn’t be your average pipeline, and tar sands aren’t your average crude.

Keystone and Tar Sands

The boreal forest

Gord McKenna

Beneath the wilds of northern Alberta’s boreal forest is a sludgy, sticky deposit called tar sands. These sands contain bitumen, a gooey type of petroleum that can be converted into fuel. It’s no small feat extracting oil from tar sands, and doing so comes with steep environmental and economic costs. Nevertheless, in the mid-2000s, with gas prices on the rise, oil companies ramped up production and sought additional ways to move their product from Canada’s remote tar sands fields to midwestern and Gulf Coast refineries.

Keystone Pipeline Map


The Keystone extension actually comprises two segments. The first, a southern leg, has already been completed and runs between Cushing, Oklahoma, and Port Arthur, Texas. Opponents of this project—now called the Gulf Coast Pipeline—say that TransCanada took advantage of legal loopholes to push the pipeline through, securing a U.S. Army Corps of Engineers permit and dodging the Environmental Protection Agency’s more rigorous vetting process, which requires public input. The second segment is the currently contested 1,179-mile northern leg—a shortcut of sorts—that would run from Hardisty, Alberta, through Montana and South Dakota to Steele City, Nebraska.

Following a rigorous, robust analysis with substantial public engagement, President Obama declined to grant the northern leg of the Keystone XL project the U.S. State Department Presidential Permit required to construct, maintain, and operate a pipeline across a United States border. Though President Trump has since granted this permit and removed this barrier to its construction, significant legal, regulatory and economic barriers remain for the pipeline to become operational.

Keystone Pipeline Environmental Impact

Leaks and the pipeline

Tar sands oil is thicker, more acidic, and more corrosive than lighter conventional crude, and this ups the likelihood that a pipeline carrying it will leak. Indeed, one study found that between 2007 and 2010, pipelines moving tar sands oil in Midwestern states spilled three times more per mile than the U.S. national average for pipelines carrying conventional crude. Within its first year of operation, TransCanada’s original Keystone Pipeline System leaked 12 times; one incident in North Dakota sent a 60-foot, 21,000-gallon geyser of tar sands oil spewing into the air.

EPA staff perform oil and sediment sampling near Battle Creek, Michigan, after the Kalamazoo spill.

U.S. Coast Guard Petty Officer Second Class Lauren Jorgensen

Complicating matters, leaks can be difficult to detect. And when tar sands oil does spill, it’s highly volatile—posing an elevated risk of explosion—and more difficult to clean up than conventional crude. People and wildlife coming into contact with tar sands oil are exposed to toxic chemicals, and rivers and wetland environments are at particular risk from a spill. “It immediately sinks to the bottom” of the waterway, says NRDC staff attorney Kim Ong, “and there is, to date, no known way of cleaning up this oil.” (For evidence, recall the 2010 tar sands oil spill in Kalamazoo, Michigan, a disaster that cost Enbridge more than a billion dollars in cleanup fees and took six years to settle in court.) Keystone XL would cross agriculturally important and environmentally sensitive areas, including more than 1,000 rivers, streams, aquifers and water bodies. One is Nebraska’s Ogallala Aquifer, which provides drinking water for millions as well as 30 percent of America’s irrigation water. A spill would be devastating to the farms, ranches, and communities that depend on these crucial ecosystems.

What is tar sands oil?

The tar sands industry is just as hard on the cradle of its business. Its mines are a blight on Canada’s boreal, where operations dig up and flatten forests to access the oil below, destroying wildlife habitat. They deplete and pollute freshwater resources, create massive ponds of toxic waste, and threaten the health and livelihood of the First Nations people who live near them. Refining the sticky black gunk produces piles of petroleum coke, a hazardous by-product. What’s more, the whole process of getting the oil out and making it usable creates three to four times the carbon pollution of conventional crude extraction and processing. “This isn’t your grandfather’s typical oil,” says Danielle Droitsch, senior policy analyst for NRDC’s Canada project. “It’s nasty stuff.”

Keystone and climate change

A fully realized Keystone XL would lead to more mining of that “nasty stuff” by accelerating the pace at which it’s produced and transported. (Indeed, Keystone XL was viewed as a necessary ingredient in the oil industry’s plans to triple tar sands production by 2030.) 

It would also lead to greater greenhouse gas emissions. In 2014, the U.S. Environmental Protection Agency stated that tar sands oil emits 17 percent more carbon than other types of crude, but ironically, the State Department revised this number upward three years later, stating that the emissions could be “5 percent to 20 percent higher than previously indicated.” That means burdening the planet with an extra 177 million metric tons of greenhouse gas emissions annually, the same impact as adding 37 million passenger vehicles to the road. Finally, the pipeline would undermine efforts to prioritize clean energy like wind and solar and to minimize global warming. Leading climate scientist and former NASA researcher James Hansen has warned that fully exploiting Canada’s tar sands reserves would mean “game over” for our climate. In short, tar sands oil represents no small threat to our environment, and our best stance against it, as the rallying cry goes, is to “keep it in the ground.”

Keystone Pipeline Controversy

Opposition to Keystone XL centers on the devastating environmental consequences of the project. The pipeline has faced years of sustained protests from environmental activists and organizations; indigenous communities; religious leaders; and farmers, ranchers, and business owners along its proposed route. One such protest, a historic act of civil disobedience outside the White House in August 2011, resulted in the arrest of more than 1,200 demonstrators. More than 90 leading scientists and economists have opposed the project, in addition to unions and world leaders such as the Dalai Lama, Archbishop Desmond Tutu, and former president Jimmy Carter (together, these and other Nobel laureates have written letters against the project). In 2014 more than two million comments urging a rejection of the pipeline were submitted to the State Department during a 30-day public comment period.

Rocky Kistner/NRDC

In the two years leading up to the November 2014 midterm elections, the fossil fuel industry spent more than $720 million to court allies in Congress. When industry-friendly politicians took charge of both congressional houses in January 2015, their first order of business was to pass a bill to speed up approval of Keystone XL. (That effort failed.)

“So what if there’s no pipeline . . . Big Oil will find a way.”

One of the central arguments by pipeline pushers is that tar sands expansion will move forward with or without Keystone XL. This has proved to be untrue. Dealing in tar sands oil is an expensive endeavor. It’s costly both to produce and to ship, particularly by rail, which would be an alternative to Keystone XL. Indeed, moving crude by rail to the Gulf costs twice as much as by pipe. For companies considering whether to invest in a long-lived tar sands project (which could last for 50 years), access to cheap pipeline capacity will play a major role in the decision to move forward or not. Without Keystone XL, the tar sands industry has canceled projects rather than shift to rail, subsequently leaving more of the earth’s dirtiest fuel in the ground where it belongs.

Keystone Pipeline Economic Facts

Will the pipeline create jobs?

The oil industry has lobbied hard to get KXL built by using false claims, political arm-twisting, and big bucks. When TransCananda said the pipeline would create nearly 119,000 jobs, a State Department report concluded only 3,900 temporary construction jobs would appear and that the number of permanent jobs would hover around 35.

Will the pipeline lower gas prices?

Dirty energy lobbyists claimed developing tar sands would protect our national energy security and bring U.S. fuel prices down. But NRDC and its partners found the majority of Keystone XL oil would be sent to markets overseas (aided by the recent reversal of a ban on crude oil exports)—and could even lead to higher prices at the pump.

President Trump and the Keystone Pipeline

When President Obama refused to grant the presidential permit necessary to build TransCanada’s Keystone XL oil pipeline in November 2015, he struck a blow against polluting powers and acknowledged the consensus on this misguided project from a wide swath of people and organizations. “America is now a global leader when it comes to taking serious action to fight climate change,” he said. “And, frankly, approving this project would have undercut that global leadership.” Obama’s decision echoed a seven-year State Department review process with EPA input that concluded the pipeline would fail to serve national interests.

Upon sweeping into office, President Trump—with his pro-polluter cabinet of fossil fuel advocates, billionaires, and bankers—quickly demonstrated that his priorities differ. On his fourth day in office, Trump signed an executive order that allows Keystone XL to move forward. On March 28, 2017, his administration illegally approved a cross-border permit for the pipeline, reversing the Obama Administration’s robust National Interest Determination process.

The opposition has been swift and strong. Within days of the reversal, NRDC and other groups sued the Trump Administration, contending that the State Department acted in violation of the National Environmental Policy Act and the Administrative Procedure Act by relying on an outdated and incomplete environmental impact analysis and by arbitrarily reversing its earlier decision.

Hurdles Remaining in Keystone XL’s Path

The Trump administration still faces numerous hurdles in its attempt to fast-track Keystone XL. For starters, the process must still meet the requirements of federal environmental law, which require objective consideration of the environmental impacts of the pipeline. Federal Clean Water Act permits are also still required. In Nebraska, a long and contentious opposition to routing the pipeline continues, and in-state opposition is in fact growing. TransCanada must seek approval from Nebraskan authorities—a process than can take 8 to 12 months, and then must still seek right-of-way access for the pipeline. Ranchers and Native Americans are ready to fight to protect the lands they have stewarded for generations.

Finally, even as Trump and TransCanada try to revive the pipeline, polls show that a majority of Americans now oppose it and the market case has also deteriorated. Low oil prices and increasing public concern over the climate have led Shell, Exxon, Statoil and Total to either sell their tar sands assets or write them down. Because of this growing market recognition, major new tar sands projects haven't been approved for years.

As NRDC President Rhea Suh said prior to President Trump’s inauguration, “Whatever we voted on in November [2016], nobody voted for dirty water and air. Nobody voted to walk away from climate leadership and millions of clean energy jobs. And nobody voted to hand over our country to a pollute-ocracy that puts polluter profits first—and puts the rest of us at risk.”

Stop the Keystone XL Pipeline

Midwest Dispatch

Historic flooding recently inundated parts of the Cornhusker State where the proposed Keystone XL pipeline would pass through. Here’s why that’s a disaster in the making.

onEarth Story

The people and the planet can claim more than a few victories—and 2019 is looking better already.


How an unlikely coalition of environmental activists stopped the destructive tar sands oil pipeline.

Midwest Dispatch

Meet some of the people who are striving to stop TransCanada’s dirty tar sands oil pipeline once and for all.

NRDC in Action

For more than a decade, we've fought to keep this filthy fossil fuel from being dredged up and piped through the United States.

onEarth Story

Five years ago, a pipeline spilled a million gallons of tar sands crude into a Michigan river—and we’re still cleaning it up.


At every turn, the Tar Sands Invasion would put people and the environment in harm's way.

Midwest Dispatch

DAPL may be underway, but the water protectors at Standing Rock taught us a lot about going up against the fossil fuel industry.

Policy Primer

Yes, Trump has green-lighted the controversial Keystone XL pipeline. But Nebraska’s got a slew of public hearings on the calendar, and legal challenges loom large.

Action Figure

The founder of Bold Nebraska has led the Cornhusker State’s years-long rallying cry against TransCanada’s tar sands pipeline.

What's At Stake

This dirty, dangerous oil, which is almost impossible to clean and affects the health of people, is bad news for our country—and the planet.

onEarth Story

Despite a court order to reassess the Dakota Access Pipeline’s environmental impact, the agency won’t share the results of its new study.

onEarth Story

Oil trains won’t get better brakes, air conditioners won’t get safer chemicals, and children lose their EPA advocate.

Join Us

When you sign up you'll become a member of NRDC's Activist Network. We will keep you informed with the latest alerts and progress reports.