Recently, parts of Europe have received a large amount of rain which has caused problems. The Prague Post reported that late May floods in the Czech Republic has had the worst flooding since 2002 and points out that the financial cost of the floods is doing nothing but creating a potentially bigger financial crisis in that nation. In Poland, the flooding took 15 lives and the comparisons there are to the flooding scenario of 1997. Apparently, after that flood event, the country made infrastructure changes to build up flood defenses. As it turns out, some of the efforts have failed. Oh…it’s not being blamed on poor engineering or construction or government regulation or public officials taking bribes. No, the flooding in Poland is blamed on beavers. The estimate is that over 50,000 beaver live in Poland and they enjoy a measure of protection, according to animal welfare services.
Now, for a long time I have wondered why it is that human activity is considered to not be natural when that activity changes ecosystems but the behavior of other mammals is thought to be natural. Beavers necessarily transform and change ecosystems. Beavers will build a dam. That dam produces a lagoon. That lagoon eventually fills up with sediments and a meadow is created. What had been a flowing creek or small river tends to be destroyed by the beaver dam and a new ecosystem that supports different types of wildlife is created from the transformation. That is considered natural whereas when man builds a dam and changes an ecosystem, it’s not natural. Hmm. In any event, man built these flood defenses in Poland and now the beaver has been digging holes. When they dig their tunnels into the sides of levees, it weakens the flood control structure and the result has been that, with swollen rivers, some of the flood defenses have failed. So, in response, authorities are upping the hunting quota on the beaver. The “unnatural” activity of man building levees are winning out against the “natural” activity of the beaver, which has been destroying and recreating ecosystems for as long as they have been around.
On This Date In History: When flooding occurs in the US and dams or levees fail, the first thing that we tend to do is blame someone. That someone is never wildlife like the friendly beaver. Typically, its some corporate malfeasance, corrupt government official or lack of governmental regulation that is at the root of the evil. Rarely do we put the cause of any event, where more often than not it should reside, at the feet of the laws of Physics. Sometimes, it’s no one’s fault and you can’t blame it on the beavers.
In June 1972, warm moist air from the Gulf of Mexico made it all the way to South Dakota. A cold front came down and 15 inches of rain fell on the Black Hills in just 6 hours. Now, the Pactola Dam was built in 1952 and it created flood control and a resevoir that made the region much more habitable. During that time, some ten miles away, Rapid City grew to nearly 50,000 and a large residential neighborhood sprang up. Trouble was, the neighborhood was situated in the flood plain. On This Date In 1972 after the torrential rains came and the deluge continued throughout the Rapid Creek Valley. Some 10-15 inches of rain fell over the Rapid Creek watershed. At the time, media reports claimed that the Pactola structure failed. It did not. In fact, post analysis estimates are that the flood control project actually saved lives and damage as it reduced the flow to the Canyon Lake resevoir. Now the dam at Canyon Lake was the one that got into trouble. A bunch of debris clogged the spillway at the dam. The dam collapsed and water was sent rushing through the neighborhood and through Rapid City. Over 4 days, 16000 acre feet of water rolled through Rapid City and the flooding resulted in the loss of 238 lives. Most of the homeowners had no insurance. Today the dam has been rebuilt. I suppose it was an earthen dam in 1972 as it is today. There’s one big difference. There is no residential community in the flood plain any more. Today it’s a golf course.
The 1972 Rapid City Flood has been revisited numerous times. As it turns out, most of the rain fell between the Pactola Resevoir and the city. In an effort to try and prevent a similar tragedy, studies were conducted but it was found that the geology precluded the construction of other dams. The conclusion was that the best course of action was to create a ”greenway” or park system in the flood plain. Hence, no more homes and business. It’s always amazing how when we look back at historical events and how shortsighted we were in doing some things, like putting homes in a flood plain. I really wasn’t anyone’s fault though. Sometimes, things just happen that are beyond man’s grasp. I guess building houses in that area was a good idea back when it was first proposed. It often seems to take a tragedy to wake people from their slumber and remember one of US Grant’s favorite lines: “Man Proposes and God Disposes.” Or, as in the case of Poland, the beaver did the disposing.
Weather Bottom Line: Things worked out as advertised…at least on these here pages. We had some fairly heavy rain with a fair amount of thunder and lightning and it happened well after midnight. I got waken up about 3:39 AM on Wednesday. Rain totals were generally from .75″ to 1.50″. It was a little more substantial in spots than I might have anticipated but I was mainly focused on the severe threat which I was not too enthused about as the timing came about as I expected. Look for fog Thursday morning. This front really didn’t bring much in the way of drier or even cooler air. So, the dewpoints are not that low and with the moisture from the rain..fog. We will be in the upper 80′s to low 90′s to wind up the week before we get another t’storm chance for the weekend.