We read in the newspaper that the current flood conditions are a “once in two hundred year” event. How would we know that? We have no written records for Lake Country before settlement, which began with Tom Wood’s pre-emption of 160 acres at the south end of Pelmewash (later Wood) Lake in 1871.
It is quite likely that serious flooding occurred annually in the bottomland between Wood and Duck Lake prior to 1908, when the level of Wood Lake was dropped by four feet due to construction of the navigation canal between Wood and Kalamalka lakes. The most likely meaning in the Okanagan (Syilx) language of “Pelmewash” is “lake that floods” or “lake that covers the earth.” Think of Wood Lake being four feet higher than it is now and then add two or three feet of water during the spring freshet. That could take the level of Wood Lake to at least Lodge Road.
After the level of Wood Lake was lowered, the valley bottom was still subject to flooding. Severe flooding occurred along Bottom Wood Lake Road in 1929 or 1930. Arnold Trewhitt remembers as a six year old attempting to take a trip from Oyama to Kelowna with his parents, John and Edith, in the family’s 1928 Chrysler. Bottom Wood Lake Road was flooded as they approached Lodge Road, covered with perhaps a foot of water. The road was deemed impassable and the Trewhitts turned back, abandoning their travel plans.
The 1930 flooding described by Arnold was more severe than what we are currently experiencing. What is different today is that considerable building has occurred on this Lake Country bottomland where structures are vulnerable to these occasional events.
There is a public policy implication arising from this issue. If a flooding event occurs perhaps once every eight generations, precautions such as appropriate zoning or protection of our infrastructure may seem unnecessary. However, these events have occurred more frequently in the past than has been assumed and flooding may well occur more frequently in the future as a result of the early melt of the high elevation snow pack. Municipal officials will likely consider how to plan for the possibility of more frequent flooding events.
Climate change is making extreme weather events far more likely across the world with 1:200 floodings or droughts becoming 1:50. The Okanagan is not immune. Global warming of Interior winters mean deep cold spells no longer knock out the pine beatle with results visible throughout the Interior forests.
Data is preferable to anecdotal reports.
The fact that flooding occurred more frequently prior to the building of the canal is not very relevant.
The statistical measure of 1/200 does not mean that it cannot happen more often than that but is statistically unlikely.
Of course, climate change may make all of the recorded data irrelevant
I guess it was relevant to people living here at the time.
Many seniors know more of an area than statistics will ever tell.
Hi Carl Shearer,
It is really difficult to find good data – impossible over a two hundred year period and problematic over shorter periods. In the absence of good data, I am prepared to use first hand anecdotal evidence, if only to disprove a specious, unsupported claim of two hundred years of evidence.