Welcome whitewater boaters to the...




So Just How Much Force Does Water Exert?

A very unfortunate accident on the Spokane River several years ago involved a canoe that was
It broached on a bridge pier. The result trapped ONE OF ITS FOUR OCCUPANTS
– a 7 year-old boy – who miraculously recovered ONLY to die months later from the effects of the drowning.

It's then interesting to look at just how much force water does exert on a structure...or body! The following illusration give, perhaps, the most simple view.


Elephants Vs. Cubic Feet Per Second

In whitewater boating w e often hear reports of how a river flows in "cubic feet per second."

To fully understand the forces at work in a flowing stream, it is helpful to visualize how many elephants it would take to equal a similar weight of water rushing by a given point every second.

For illustration purposes, a cubic foot of water equals 7.5 gallons and weighs 62.5 pounds. An average mature bull elephant weighs 10,000 pounds (5 tons).

So a mere 1,000 cubic feet per second, the flows that might be found in the Spokane River in late summer are about equal to the combined weight of six elephants. Imagine the crushing power of having six elephants sit on you and you have an idea of the power contained in water.