Created on Thursday, 13 March 2014 22:23 Published Date Hits: 2472
Riverside is an old dance hall turned into a café called the Stage Stop, and is also the name of the cluster of houses that begins next to the dance hall and runs north from the Musselshell River a couple of miles outside Roundup. It’s an area susceptible to flooding, most recently remaining waterlogged for weeks during the unprecedented flood in late May and June 2011.
Now, nearly three years later, the Musselshell was in flood again. Highway 12 west, toward Lavina and other towns upriver, was already closed. This late winter flood of 2014 had come on almost as abruptly as the one in late spring 2011. And again, most Riverside residents had been forced to button up their homes as best they could and abandon them, joined by others living in the nearby lower-lying areas of Roundup.
Elizabeth and I, like most Roundup residents, live on higher ground above the flood plain, but to travel a highway any direction but north, everyone has to drive through the floodplain. We were scheduled to cross the Musselshell and get to Billings to catch a plane on March 11. However, by March 10 National Guard personnel were gathering as waters began to lick the edges of that road, so we hastened our packing and managed to scoot by and cross the river lest the road be closed as it had been, off and on, for three weeks in 2011.
The U.S. Geological Survey’s gauge for this part of the river is at Riverside. At this site when it reads 10 feet, the river is in flood. The high point of the 2011 flood came on May 26, when the reading was 14.78 feet— the highest ever measured at this point in the valley.
This winter, 2014, periods of freezing (sometimes very deep freezing) and snow have alternated with warming and melting. At the end of February the Roundup area had lots of snow, and only gradual warming, and USGS measurements show the river running with little variation at one and a half feet until Friday, March 7, when the air had warmed enough for snow to melt and flow and the river to begin a steep rise.
From 1 ½ to 4 feet by the end of March 7. From 4 to 6 feet on Saturday the eighth, then on Sunday the ninth all the way up to 12 feet. As I write this, Monday evening, the 10th, using a friend’s computer in Billings, Highway 87 is closed to all but emergency travel – and may soon be closed, period – with the water level at Riverside standing above 13 feet.
That places this event third in a list of floods measured by the USGS at Riverside since 1946: the 2011 flood at 14.78 feet; an event March 3, 1979, which topped out at 13.79 feet and probably, like this present one, was exacerbated by ice holding up the flow, holding up the flow, then releasing it suddenly; then this one which – who knows? – could keep rising, since snowmelt was being augmented by rain.
More frequent and more intense weather events: This is happening all around the planet. More extremes. Of course, in Montana, we are used to extremes. The trajectory in the Musselshell Valley from 2011 to 2014 was from extreme snowmelt and runoff and rains in May-June 2011, rains that abruptly stopped as the flood waters were receding by July, to be replaced by 22 months of very dry weather – leading to forest fires destroying hundreds of houses and barns in the Bull Mountains south of Roundup in summer 2012 - and suggesting worse to come when the winter of 2013 stayed dry.
Everyone was looking at another hot, dry summer in 2013; ranchers were cutting back on livestock fearing that no rains meant no grass; farmers were considering what crops to plant. Then in mid-May the rains returned, and over the next seven months, to mid-December, our backyard rain gauge collected 25 inches of rain or snowmelt. Remember, this is semi-arid country. Roundup gets an average of 12 inches of precipitation per year (if “average” means anything anymore). Billings gets a bit more – 14 inches average – but while Billings had a better than average year, it did not come close to what our backyard in Roundup enjoyed.
Since mid-December, snow-melt in our backyard has added another 2.2 inches. (I keep saying “in our backyard” because I suspect our figures may deviate from whatever the official precipitation is for Roundup.) Where does all this water come from? Well, climate scientists point out that as the global temperature rises, more water evaporates. And it has to go somewhere. Why not here?
There’s some great balancing act going on in our atmosphere that even the most insightful climate scientists do not – cannot – fully understand. During this same 2011 to 2014 period, the entire state of California, north and south, was gripped by a brutal drought. Perhaps the rains are starting to return to California, the snows to the mountains, but if so, doesn’t that suggest that somewhere else it will suddenly turn very, very dry?