The question has never been whether the Keystone XL pipeline will leak, but when and where.
Will thousands of gallons of dirty tar sands oil be dumped into the Yellowstone River or Platte Rivers?
Or will it be one of the thousands of other streams and rivers that quite literally give life to the fragile plains ecosystems in the proposed pipeline's 1,700-mile path?
Remember, this is not idle sky-is-falling speculation. Federal officials assure us the Keystone pipeline, which would transport up to 35 million gallons of tar sands oil a day from Canada to Texas, could spill up to 100 times during its lifetime.
Now, just as the U.S. Senate pushes toward a vote on the Keystone XL pipeline, the escalating environmental and human cost of that reality has been brought into sharper focus by a new analysis of all "significant" U.S. pipeline incidents since 1986.
The report, released this week, is based on federal Pipeline and Hazardous Materials Safety Administration records of pipeline incidents resulting in death or injury, damages of more than $50,000, the release of more than 5 barrels of highly volatile substances or 50 barrels of other liquid released, or incidents where there was an explosion or fire.
The new analysis comes as the State Department considers the Keystone XL pipeline and Republican members of Congress push for a vote on an amendment to bypass President Obama and require Keystone be built.
A time-lapse video of the data depicts the nearly 8,000 "significant" pipeline incidents, resulting in more than 500 deaths (shown as red dots on the video), more than 2,300 injuries (yellow dots on video), nearly $7 billion in damage, and an average of 76,000 barrels of oil and gas spilled every year.
This amounts to an average of 300 incidents every year, one every 30 hours.
Which hour will be Keystone XL?
How bad will it be?
Time is running out for our president and our U.S. senators to insist that we never have to learn the answers to these questions.
Noah Greenwald is endangered species director at the Center for Biological Diversity.