Pipeline © Nataliash | Dreamstime.com

Pipelines leak for more reasons than excavation mistakes. In fact, recent data tells that corrosion is their greatest enemy. Photo © Nataliash | Dreamstime.com

April has been named National Safe Digging Month according to 811, the people who have made it very easy to find out if you might be on the verge of cutting a power line, cable, phone or natural gas line as you dig around on projects.

Many utility companies and pipeline operators such as Koch Pipeline Co LP are putting out press releases reminding people to call before digging. In one such release, Koch reported that according to the Common Ground Alliance, 49 percent of Americans who plan to dig this year will not call 811 to learn the approximate location of underground utilities. The release points out also that other data shows an underground utility line is damaged by digging once every three minutes nationwide, and in one-third of these incidents, the digger did not call 811. That statistic alone should tell us something. If two thirds of the diggers did call 811 then there must be a lot of sloppy excavating going on, or the people who mark the lines aren’t very accurate. We’ve all come across utilities that were well outside the colored lines or flags. Here’s what the utility marking colors mean, according to 811:

  • Red – Electric
  • Orange – Communications, Telephone/CATV
  • Blue – Potable Water
  • Green – Sewer/Drainage
  • Yellow – Gas/Petroleum Pipe Line
  • Purple – Reclaimed Water
  • White – Premark site of intended excavation

When it comes to pipelines the potential problems are multiplied since they usually carry petroleum compounds that make a mess of the environment when they escape. Some people along the route of the proposed XL Pipeline have been active in trying to prevent the line from being built because of the evidence that pipelines are far from leak proof and the majority of the time when they spill their contents it is because of pipe corrosion, equipment failures and unknown reasons.

Of 259 pipeline incidents reported from March 2010 to March 2012, 175 were termed “serious,” meaning that according to the Pipeline & Hazardous Materials Safety Administration, or PHMSA, they involved a fatality or injury requiring in-patient hospitalization. Of that total, 16 fell into the category of “Excavation Damage” and 5 of those were the either the result of the operator’s mistakes or were damage done during previous excavations. That makes the damage from excavation by third parties just 6 percent of all the causes of pipeline incidents. What’s the greatest cause during this time frame? Actually, they fall into two categories, and both are under the control of the pipeline operators – equipment failure and corrosion failure at nearly 29 percent and 17 percent respectively.

Here’s how recent serious incidents involving pipelines stack up by number of failures reported out of a total of 175, according to this PHMSA database.

  • CORROSION FAILURE – 50  (internal and external corrosion)
  • EQUIPMENT FAILURE – 30 (pressure relief valves, couplings, threaded connections, fittings, compressor equipment failures and loose tubing)
  • OTHER INCIDENT CAUSE – 28 (unknown or miscellaneous)
  • EXCAVATION DAMAGE – 16 (includes also, damage by the pipeline’s own contractors or by the pipeline operator itself)
  • MATERIAL FAILURE OF PIPE OR WELD – 22 (fabrication, construction and installation mistakes, or original manufacturing was not up to standard)
  • NATURAL FORCE DAMAGE – 14 (lightening, earth movement, rain/floods)
  • OTHER OUTSIDE FORCE DAMAGE – 9  (coastal and oceanic fishing, cars and trucks, electrical arcing)
  • INCORRECT OPERATION – 6 (over pressurization, valves left open or in wrong positions, equipment not installed correctly)

Even though pipeline damage caused by third party excavators is low, there’s no substitute for caution in both making sure to get marks put down and in recognizing those marks might not be as accurate as we’d like. Beyond excavating though, Call Before You Dig month should also serve to remind pipeline operators that they have a ways to go in their efforts to prevent pipeline leaks, and that claims of pipeline safety should be balanced with reality.


%d bloggers like this: