My 1/20/08 Missoulian column
Mark Twain wrote the old war horse about the West that goes, “Whiskey is for drinking and water is for fighting.” And in the late 19th century, you might easily have gotten into a fistfight if you were caught sneaking around at night raising irrigation headgates and diverting more water than you were entitled to into your hay fields and orchards.
One reason people stole water back then was spring runoff was hard to predict. Even 20 years ago, when I lived in the Bitterroot Valley, I’d talk with ranchers who would watch coulees as snow levels rose during the spring melt. They’d get a gut feeling about how much water would be coming down from mountain lakes in late summer, and whether they’d have to sneak around stealing water in June, they joked.
Nowadays, the business of water is just as serious, though probably less dangerous to life and limb. Across the West, 50 percent to 80 percent of water comes from snowmelt. Agriculture – the No. 1 industry in Montana – and recreation and conservation concerns – from boating to endangered trout – depend on predictions of how much water will come down from the mountains in the spring.
The modern world works on data, and when it comes to determining snowpack, it’s no different. Instead of watching mountain coulees, many people now check a Web site called SNOTEL, which is run by the Natural Resources Conservation Service’s National Water and Climate Center.
SNOTEL – short for “snowpack telemetry” – is a system of more than 700 solar-and battery-powered data collection stations in the mountains of the Western U.S. and Alaska that radio in snow and moisture data at least every hour. That data is, in turn, error checked and crunched by computers at the National Water and Climate center in Portland, Ore. Packaged into weather and climate data sets, the numbers are used for snow and water availability forecasts, climate science and forecasting, emergency planning and hydropower generation.
SNOTEL had a very lowtech start in the 1930s with what are still called “snow courses,” trails mapped out for travel on ski and snowshoes by workers who measured snow depth and calculated water content with handheld instruments. The courses weren’t haphazardly chosen; shady meadows keep snow longer, as do north-facing slopes and coulees, and the courses were designed to have an even distribution of snow for accurate depth measurements.
The snow courses and collecting sites quickly evolved in the early 1980s with the introduction of a radio system that uses the reflective trails of meteor bursts to bounce signals around the region. Tiny dustsized meteors burn up night and day in the upper atmosphere, leaving an ionized trail that reflects radio signals.
The snow stations bounce transmissions off these trails, exchanging data and receiving commands from central control stations. Meteor trails are old news to ham radio operators, who have been using the “skip” system to bounce radio signals around for years, and using them with the snow courses was enough to end the era of data collection by ski and snowshoe.
You can see all the data that the SNOTEL system collects here, from current, hourly figures for snowpack and water content to historical data, as well as temperature data.
Most readers might be interested in the current average of snowpack for river drainages in Montana. Right now, most are a bit more than 100 percent of average, which is very good in this La Nina year, as we closed out last year nearly 3 inches below average total precipitation.
In other parts of the SNOTEL site you can drill down to the exact snow course; there are four in Missoula Country, and the closest one to Missoula is the Lubrecht Flume near Potomac. One day last week, there was a foot of snow with a water equivalent of 2.7 inches and year-to-date total precipitation of 5.2 inches.
If you really want to play with SNOTEL information, NRCS has started offering data sets in Google Earth format. That means you can download a layer file and use Google Earth on your computer to fly around the West and zoom in on a mountain range with all of the SNOTEL stations flagged and reporting their data.
Today, in the 21st century, it’s easier to check the SNOTEL site to see if you’re going to have enough spring runoff than girding for a fight. And Mark Twain’s words on whiskey and water? Memorable, but few are sure Mark Twain actually said them. If he were around in the SNOTEL era, he might say that with all the numbers available on the Web, one should go roll in the snow once in a while to get a feel for what water really is.