In the West, water is a critical but limited resource for people, fish and wildlife. Parceling it out requires accurate data.
How high are river levels on a given day? How much water is moving downstream each second?
Since the late 1800s, the United States Geological Survey has relied on river gauges to capture that kind of information. The federal agency built its first one along the Rio Grande in New Mexico in 1889. Soon, the USGS was erecting river gauges all over the West.
One of the Northwest’s oldest is still on the job on the middle fork of Idaho’s Boise River, where it’s stood since 1911. Thanks to new technology and a modern mission, this centenarian is no longer your great-great grandfather’s river gauge.
U.S. River Gauges
- 9,000 Nationwide
- 257 Washington
- 219 Oregon
- 212 Idaho
The Boise River is fed by melting snow that originates within the Sawtooth Mountain Range of central Idaho. It twists and turns through forests, open range, and the city of Boise, Idaho’s most urbanized landscape. After 102 miles it empties into the Snake River on the Oregon border.
Along the way, gravity forces the Boise River’s water through hydroelectric turbines that generate power. It’s impounded behind dams for farmers to divert into canals to irrigate crops. Cities draw water from the river for drinking and industrial uses. That’s not to mention fish, wildlife and recreation-seekers needing water to stay in stream.
Demands were just starting to compete for the Boise River when the U.S. Geological Survey constructed the Twin Springs river gauge. A year later it started turning out data. Today, there are 688 similar gauges in the Northwest.
First U.S. River Gauge
- Rio Grande, New Mexico (1889)
Greg Clark, an associate director with the USGS, oversaw the Twin Springs river gauge early in his career. He returned to the site on the Boise River recently with colleagues in a hybrid SUV.
It wasn’t always this easy to reach. When the gauge was first constructed, USGS employees had to brave the elements on horseback or in the earliest of automobiles.
“I’ve actually seen pictures of them sitting beside their Model T with bandoliers and pistols on their hips,” says Dave Evetts, who oversees all of Idaho’s USGS river gauges. “So it was a very different environment but even back then they realized how important it was to keep track of this resource.”
The Twin Springs gauge stands like a sentinel on the bank of the Boise River’s middle fork. This 10-foot-tall corrugated metal silo has measured a century’s worth of brawling runoff in springtime and icy winter flows. A tube extends down the bank and into the river. It’s gathering data on temperature, flow, water level and pollutants.
“This is one of the oldest ones that we’ve got and it’s stood the test of time,” Clark says. “And the information that’s it’s providing is just invaluable.”
Evetts opens its chest plate of a door. A shelf inside holds two boxes. One collects and calculates data fed from the tubing. The other sends that information to antennae on the building’s crown, which transmit to satellites overhead.
The Twin Springs gauge was equipped with satellite technology in 1984. But two years later the gear was stolen. It took 16 years to be replaced. The information is fed to the USGS and updated every hour on its website.
Tim Merrick is the technical information specialist for the USGS. He explains that while this outhouse-sized shack doesn’t look like much, its service is more valuable than ever. That’s because it’s producing data that’s accessible by anyone with an internet connection — a big change from the days when the information went into an annually published report to other government agencies.
“Streamflow information from a gauge like this one behind me is used by everyone from the average citizen who wants to come out here on a weekend and go fishing or rafting,” Merrick says.
Twin Springs at a Glance
- Built in 1911
- In 1952, data could be requested by citizens.
- 1962, data was included in the USGS annual data report.
- 1984 Satellite System installed.
- 1986 Satellite system stolen.
- 2003, new satellite system installed and information accessible on the web.
The river gauge data is also used by meteorologist like Doug Iverson, who forecasts the weather at KPVI-TV in Pocatello, Idaho. He uses the river gauge information to let viewers know when the river levels get close to flood stage. “It’s my job to get that information to them as quickly as possible so the public can make a judgement on what they need to do to protect themselves” says Iverson.
In recent years, river gauges in the Northwest have been used to determine the rate of climate change. Scientists can now track changes in the Boise River’s temperature over multiple years.
“We can see since the ‘60s and ‘70s that the water is coming off earlier and it’s melting in the mountain quicker,” says the USGS’s Clark. Three weeks earlier, which has serious consequences for water users and water managers.
A few months ago, Congress considered ending funding for some river gauges. In the end, it decided to keep all of them operating through the current budget cycle. Clark says he’d like to think the century old Twin Springs river gauge will be doing it’s job on the Boise River for the next 100 years.