"Paddlec1" wrote in message
...
It might be worth noting that the high water on the Columbia would not
necessarily have started with the coming of spring. Although the lower
elevations that feed the river would run off sooner, snowmelt in the
higher
areas would not peak much before June, if that early. Lewis and Clark had
time
for a spring run up the river.

Since the source of the Columbia is in the Canadian Rockies, where I paddle
(I've never actually paddled the Columbia, but I have paddled several of its
tributaries), I can feel confident in saying that while it varies depending
on location, peak flow tends to be late in June.

-Paul