SILENT ‘TIL THEY KILL

By Lance Olsen, Unfiltered 5-12-06

I’m pretty sure that the recriminations will be buzzing right along by the time citizens in boats start picking bodies out of Flathead Lake.

Last I heard, the number of people who went down with the Twin Towers was something over 3,000. Last I heard, the body count in post-Katrina New Orleans was maybe 1,500 and counting.

Our thing here in Montana will be a tad more deadly than that.

In 1987, the Bureau of Reclamation reported that a "maximum credible" earthquake near Hungry Horse Dam would fracture it, and "would endanger 15,000 lives."

Actually, 15,000 might be a tad low. Since 1987, thousands more have set up homes and businesses right smack dab in the path of the hugely violent flood that would follow on the heels of the quake.

In January, this year, Governor Schweitzer ordered up a drill for emergency planners in western Montana. Collapse of Hungry Horse Dam was the scenario. Evacuations were the order of the day. Seventy thousand people, or more.

In the January scenario, though, the dam didn’t come down due to a geologic jolt. Instead, planners could know beforehand that Hungry Horse Dam was in danger. They could even calculate the risk of collapse with some fairly handy data.

Snowpack information, when coupled to weather forecasts, can offer advance warning that a dam might be endangered by an extreme of runoff. Lots of rain on top of lots of snow can make an ugly scene, as when rain-on-snow weather threatened to take down Gibson Dam on the Rocky Mountain Front. In the January drill, emergency reponders had three days to evacuate the estimated seventy thousand men, women, and children, including many newcomers who haven’t a clue of dam safety – or Montana’s earthquake history.

Montana is one of the four most seismically active states in the nation, and the mountains and valleys of western Montana are where the next big quakes are most likely to whack us. Montana’s own website on earthquakes http://dma.mt.gov/des/Earthquakes.asp drops little clues such as these:

------------
"By far, earthquakes pose the largest single event natural hazard faced by Montana."

"In all of western Montana an event of magnitude greater than 5.0 can be expected every 1.5 years, a magnitude of 6.0 or greater should occur every ten years, and a magnitude 7.0 or greater should occur every 77 years."

"Montana has experienced many major earthquakes in the past. There is every reason to believe that similar events will occur in the future."
------------

Major earthquakes, FEMA calmly explains with all the dry understatement we ordinarily associate with laconic humor, are "infrequent occurrences with potentially great consequences."

Then, drifting slightly closer to where things can begin to get a bit edgy, FEMA mentions that jurisdictions don't see big quakes as an immediate risk, and thus give their time to concerns of the here and now. A bit more bravely, FEMA declares that unless the risks of big quakes are reduced, cities and citizens will remain at risk.

Conclusion : The cities and citizens located downstream from Montana's Hungry Horse Dam will remain at risk because the quake big enough to drop the dam will seem far away until the cold winter day it finally drops the dam. Because that day seems a distant one, the dam will not be replaced by a safer, lower dam or dams that could slash the risk of a nasty quake-flood combo, produce the same amount of hydropower, and inundate a lot less wildlife habitat than the current high dam does.

So, I suspect, the recriminations will be buzzing along quite nicely by the time citizens in boats are picking bodies out of Flathead Lake.

Like this story? Get more! Sign up for our free newsletters.