The PG&E gas line explosion that took eight lives on Sept. 9 is being pinned on poor data entry and omissions in the GIS system. The exposé by the San Francisco Chronicle says that the lack of reliable information in the database and mapping system should have caught the defective seam that was the cause of the explosion. Poor record keeping about pressure tests, with no record on 30% of their 1,800 miles of gas transmission lines could also result in a complete shutdown of their lines unless they produce records by March 15.
The piece goes on to quote a paper that was presented at the 2004 Esri User Conference in San Diego, where the presenter remarked that data validation was an issue that led to incorrect and inconsistent values in the database. The ‘garbage in, garbage out’ adage applies here, yet in this case the errors had critical safety implications. Ironically, the organization used the existence of their GIS system as a defense for foregoing a more detailed and costly inspection of their lines, because they insisted that they had adequate records. The use of the in-pipe sensors known as smart pigs would have filled in the gaps in this data, and helped to find the weld weaknesses responsible for the rupture.
There are elements to the Chronicle’s report that seem to suggest that the system itself is liable, rather than the operators or the quality control measures that were put in place. There are words to the effect that the GIS system faltered and was partly to blame, although it distinctly appears that management treated lapses and failures in the system too casually.
Clearly, this case emphasizes that the most critical infrastructure are often our records about our infrastructure. Infrastructure degrades over time, and is tied very closely to public safety and our economy. Those that profit from the infrastructure have a regulated obligation to inspect and maintain it, but perhaps after this incident inspections of the systems used to maintain our infrastructure are in order.
Read this detailed feature here.
