Hydrologists label floods according to their probable frequency or periodicity. Great floods occur less frequently than small floods, and that leads to classifications, such as “five-year flood,” “ten-year flood,” “100-year flood,” and on through periods of longer duration. The frequency is tied to the probability and is based on historic or records where they are available or on geologic detective work.
A five-hundred-year flood can devastate farms and buildings and cause injury and death. Unfortunately for victims, getting one 500-year flood doesn’t eliminate the possibility of a recurrence for 500 years. Two such floods could occur in consecutive years, but another one might not occur for a 1,000 years or more.
Between floods of similar dimension, people living on a floodplain wait, not knowing when the next flood will occur, but having an approximation of when it will.
Our lives are often marked by waiting times. We know there’s inevitability to certain occurrences, but we have only approximations to guide us. Of course, that engenders a bit of anxiety in some people. A temper tantrum or a flood is coming. You probably can’t stop either, and you can’t precisely predict the moment of arrival. You simply go on waiting, even if not consciously.
Waiting times vary with types of events, of course, and not all events have an anticipated intensity. All waiting times for natural phenomena like floods, earthquakes, major storms, and volcanic eruptions are averages. Hurricane Floyd caused a 500-year flood in 1999. In 2016 Hurricane Matthew appears to have matched Floyd’s intensity. Two 500-year floods within two decades: People along the Tar River in North Carolina had recovered from Floyd only to be inundated by Matthew. What are the chances?
The intensity of the events as marked in probable frequency is irrelevant here. What is relevant is that like all of us, you have waiting times for events both pleasant an unpleasant, events both mild and intense, events both innocuous and catastrophic.
What are the events you expect, if not in daily consciousness, then in some background of anticipation or anxiety? How have you ranked them according to their intensity? Are we talking about tantrums, floods, or hurricanes? What periodic event do you await? And how long is the waiting time?