Friday, May 06, 2011

When Pend Oreille Floods

I'm experiencing deja Vu all over again. Moving to Bayview in 1995, I had arrived just in time for an awesome ice storm, followed by a flood. I have seen many rivers flood. After all, I lived most of my life in the valleys of Western Washington. There, either the Green River or the Cedar flooded about every other year, until they finally built flood control dams. I had never seen a lake flood before.

In some ways it was fun, as in an interesting experience. In other ways it was terribly destructive to the marinas and other waterfront businesses. The primary sources of water for the lake are Pack River and the Clark Fork. The Clark Fork runs all of the way from the continental divide in Montana, into Lake Pend Oreille. During high water years, millions of gallons of water flow into the lake, with the Pend Oreille River it's only outlet. With the dams at Cabinet Gorge, a few miles up the Clark Fork, and again at Albeni Falls, near the juncture of the Pend Oreille River and Priest River. That is the lake's only outlet. a bottleneck, if you will.With three rivers plus numerous streams and springs feeding the lake, add snow melt and the outlet is overpowered. Ergo, the lake floods.

With the snow pack averaging 150% in north Idaho and western Montana, and in some places, 180%, A moderate to major flood is looming. How much water we get will depend on the weather. If we get a sudden warming trend with a lot of rain, the high snow from the divide will start rolling down the Clark Fork with nowhere to go but up.

Some things to know: Timberlake Fire District has about 600 sand bags located at the Bayview station, with many more at close reach. Lakes Highway district provides the sand and individual volunteers provide the shovels and operators. 1997 floods brought the Idaho National Guard into Bayview as well, though they may be deployed in Afghanistan this time around.

Flooding can be expected at all of the marinas, as well as the large parking lot in the middle of town and the low lying condos at Boileau's. The one thing that is positive in all of this is the fishing is great, since the mud line comes all the way down lake to Cape Horn, leaving just the southern end of the lake for fish to find clean water.

Look for all of this, depending on the weather, to happen in early to mid-June, just about one month from today.

Flood history:
pre-dams
1948 2071.62
1950 2067.11
Post dams
1997 2065.74
1972 2065.70
1974 2065.47
expected in 2011
2066 to 2067 above sea level.

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