The pipeline problems that shut down the largest U.S. oil field early this month brought a chilling reminder of what can go wrong with the extensive, aging maze of pipelines that carries volatile fuels across the nation.
Poor pipeline maintenance led to extensive corrosion and leaks, leading oil giant BP to turn off the spigots at Alaska's Prudhoe Bay. Energy markets were roiled, but no human lives were threatened in Alaska's North Slope wilderness.
California's unusually large web of oil, fuel and natural gas pipelines also has been plagued with corrosion and other maintenance and safety issues. Here, however, the risk is compounded by the spread of suburbia, where houses now crowd pipelines that were built and buried in the middle of what was nowhere.
Sometimes, pipelines can be deadly neighbors.
On a November afternoon in 2004, a backhoe digging a water main trench in the Bay Area community of Walnut Creek tore into a high-pressure fuel pipeline that wasn't supposed to be there. The resulting fireball killed five men and injured four.
It was the worst in a multi-year string of accidents involving California fuel lines owned by Kinder Morgan Energy Partners. State regulators, who are still conducting a criminal probe, slapped the Houston company with $640,000 in fines after an investigation found that Kinder Morgan employees failed to accurately mark the pipeline's location.
In August 2005, federal regulators branded Kinder Morgan's Western pipes "a special risk to surrounding life, property and the environment." In April, the nation's largest fuel-line operator agreed to spend $90 million on safety and maintenance upgrades. Spokesman Larry Pierce said last week that the company "is very committed to public safety."
Considering their pervasiveness and the huge volume of oil, gasoline and natural gas that travel through them daily, pipelines are considered relatively safe. Most are buried three to four feet underground, and they stay there, unnoticed and undisturbed, for decades.
"It's not as if everybody has a pipeline in their backyard that's about to explode," said Bob Rackleff, a board member of the Pipeline Safety Trust, an advocacy group that formed in Bellingham, Wash., after three boys were killed by a natural gas pipeline explosion in 1999. "I define the problem as low-risk, high-consequence. But the risk is increasing because they are not maintained."
The group's executive director, Carl Weimer, said BP's Alaskan corrosion problem "is probably not isolated."
"I think it's one of those things where a lot of the industry will kind of wake up and check their own systems now to make sure they're not having the same types of problems, and my guess is that Congress is going to force them to do that too in the coming months," he said.
In California, that would be a massive undertaking.
The state, home to prolific oil fields that date as far back as 1899, has long been fertile ground for wells, refineries and gasoline-guzzling automobiles. That led to the construction of huge webs of pipelines to connect oil fields, refineries, storage tanks, ports, airports, military bases, offshore drilling rigs and more.
Today there are about 6,000 miles of active "hazardous liquids" pipelines in California, with most carrying crude oil or petroleum-based fuels like gasoline, diesel and jet fuel, according to the state fire marshal's pipeline safety division, California's primary watchdog for that infrastructure.
Pipelines that carry natural gas are ubiquitous because they deliver the fuel to individual houses as well as power plants and other facilities.
California has more than 12,000 miles of the larger, long-haul transmission lines and 98,000 miles of distribution lines -- the smaller pipes that carry natural gas into neighborhoods -- according to the federal Pipeline and Hazardous Materials Safety Administration, an arm of the Transportation Department.
But many of California's pipelines are at least 50 years old, prone to corrosion and under threat from Mother Nature as well as backhoes and other kinds of human interference.
Bob Gorham, chief of the state's pipeline safety division, is convinced that anti-corrosion coatings and technologies, together with high-tech diagnostic tools and the periodic testing required by California and federal rules, are sufficient to root out most pipeline flaws before they cause leaks.
"I think [Californians] should rest assured that they're well-maintained and tested and are the safest way to move the product," Gorham said of the state's petroleum pipelines. "We have 6,000 miles of pipeline, and we have less than a dozen leaks a year. And we feel confident that we know every inch of every pipeline."
Julian Ajello feels similarly sanguine about California's natural gas pipelines, most of which are regulated by the California Public Utilities Commission.