Archive for January, 2018

An Independent Forensic Team has published a 584-page report on the catastrophic destruction of the Oroville dam spillway last winter. The report summary states the catastrophe was the result of long-running systemic failures at both the State and Federal levels.

The entire report makes for fascinating (and scary) reading, but there is one part that really stands out:

A contributing factor to DWR’s overconfidence and complacency was a somewhat widespread belief within DWR that the SWP was designed by the “best of the best” – a belief passed on through two generations to the current generation, and possibly increasingly mythologized by each generation. While it is true that DWR recruited nationally to hire qualified engineers and geologists from other organizations, it is unlikely that DWR was able to fill all of its key engineering and geology positions with the “best” people, given the rapidity with which DWR needed to scale up its organization during the 1960s.

The most relevant possible illustration of this aspect is that, as reported to the IFT in an interview, the principal designer for the Oroville spillways 1) was hired directly from a university post-graduate program, with prior engineering employment experience limited to one or two summers for a consulting firm, 2) had no prior professional experience designing spillways, but had received instruction on spillway design in university coursework on hydraulic structures, and 3) likely did not consult technical references regarding spillway chute design, and instead relied on notes from his university coursework in hydraulic structures. If this information is accurate, the IFT finds it striking that such an inexperienced engineer was given the responsibility of designing the spillways of what is still the tallest dam in the US.

Damaged Dam


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According to Australian mainstream media, Bicycle Network is that country’s one and only group for representing the interests of cyclists. This is the organization which, for the past 30 years, promoted mandatory helmet laws. With friends like that who needs enemies?

But now, I guess in an attempt to stay relevant, Bicycle Network has been conducting a highly publicized survey on the issue of mandatory helmet laws. The good news is that the survey result showed agreement on repealing Australia’s mandatory helmet laws. However, a substantial number of respondents (40%) want to retain the law for children.

This survey result is typical, especially when the bicycle gearheads discuss helmet laws on the internets. Children, it is argued, need to be protected because they are more vulnerable to traumatic head injury. Like everything else involving helmets, that argument is based on superstition instead of hard data.

Children are actually not all that vulnerable to head injury. In fact, if there is one age group extremely vulnerable to traumatic head injury it isn’t children but the elderly. Rates of head-injury deaths in the US were highest for those aged 75 and older. Similar results are seen in Europe. From a safety standpoint, it is ludicrous to single out the age group least at risk:


TBI-associated death (Eurostat)

Now to be clear, this data is for all TBI-related fatalities, not just ones involving a bicycle. The point here is to show that children do not have some biological issue that requires special head protection.

And of course, we already know that mandatory youth helmet laws is ineffective by looking at places that implemented such laws, including California and parts of Canada. Oh, and Australia.


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