I spent some time yesterday reading about an interesting issue concerning an old and famous disaster. The name “the Johnstown Flood” is well-known, but the details of the 1889 dam failure that killed over 2000 people are not so much any more.
In short, western Pennsylvania is rough terrain, with narrow river gorges cutting through the Allegheny Mountains. The state government built an earth dam on the south fork of the Conemaugh River to provide a water supply for a canal that was intended to compete with the Erie Canal to the north. When the canal was superseded by the Pennsylvania Railroad, the dam was effectively abandoned. It was later sold to the South Fork Fishing and Hunting Club, run by a group of wealthy industrialists from nearby Pittsburgh, so that the impound lake could be used for fishing. The failure, from rain-induced flooding, of a minor dam used for the recreation of a handful of men led to unimaginable death and physical destruction.
The paragraph above has all been pretty well understood since the dam attracted public attention 131 years ago. My reading yesterday started with Civil Engineering magazine’s monthly ethics discussion, which posed a question about the contemporary forensic investigation of the collapse. I knew that there had been an investigation, but did not know (or did not remember) that the investigation had been officially under the ASCE name. The results of that investigation were kept sealed for 18 months and, when released, turned out to have an ambiguous conclusion: some poorly-thought-out modifications to the dam by the club had weakened the dam, but it would have collapsed regardless because of the effect of the triggering storm. The ethics question was based on an unnamed researcher’s recent “manuscript making the provocative argument that the ASCE team intentionally watered down its findings about the cause of the dam’s failure.” Specifically, that the 1891 report ignored the extent of the bad modifications and did so because the team leader, the ASCE president at the time, was a railroad engineer with social and business ties to the owners of the club. The bad alterations, which reduced the capacity of the spillway and removed an emergency drainage system, were not news to me, but the conflict of interest was. (Anyone looking for a general history should, in my opinion, start with The Johnstown Flood by David McCullough.)
It turns out that the recent manuscript mentioned is one of several linked publications, which appear to have started with “Dam-Breach hydrology of the Johnstown flood of 1889–challenging the findings of the 1891 investigation report” by Neil M. Coleman, Uldis Kaktins, and Stephanie Wojno. The paper begins by examining the hydrology of the dam as built and as altered, and then moves on to the old report. Mr. Coleman has, more recently, directly stated that the conflict of interest tainted the report.
So, I had a fascinating time with some reading. Beyond the rather basic and well-known conclusions that conflicts of interest and other ethical compromises are inherently bad, and that reducing the outflow capacity of an earth dam is both stupid and potentially lethal, what is there to learn? When I studied history, I heard again and again that, while there are objective facts, it is almost impossible to separate them from people’s subjective perceptions. It is a fact that more than two thousand people died at Johnstown; whether you believe that to be an act of god caused by a abnormally heavy rainstorm, the result of rich men neglecting maintenance of a leisure property, or somewhere in between is purely subjective. This type of discussion is normal in the social sciences but rare in engineering. Engineers, as a group, like hard facts and often are uneasy discussing perceptions. Perhaps it’s easier for us when dealing with a failure that took place so long ago.