Recently my mother, who lives in Tennessee, called me. She was concerned. Like dutiful parents everywhere, she keeps tabs on the weather where each of her children live, and she had just seen a flood warning in Boise’s weather forecast. Were we okay, she wondered. We’re okay, and since we live several miles from the Boise River my family will likely remain safe from flooding. But others might not be so lucky. Also, I let her know she should get used to seeing that flood warning, as it’s apt to remain well into summer.
How Much Precipitation Is Idaho Getting?
Though I am writing this in Boise-where precipitation is 161% of average for this time of the water year and the river is breaking records for high flows-all of Idaho is experiencing an epic water year. Every basin in the state has received precipitation well above average since Oct 1, the start of the water year. In fact, as of today, the basin with the lowest amount of precipitation is the Clearwater-at 122% of average. Not too shabby for an arid state.
Average precipitation doesn’t tell the whole story though. Another way to look at our situation is to ask, how much water is in Idaho’s snowpack? The metric used for this is snow water equivalent (SWE), which tells you how much water is left to melt. At 99% of average, the current lowest SWE in the state is in the Spokane basin. It’s virtually unheard of to have such a high low. The highest SWE? The Big Wood basin’s astounding 196% of of average! With snowpacks like these remaining this far into the year, Idaho rivers will likely be flowing high for months to come.
What Does This Mean in the Short Term?
If you love recreating on rivers, this could be your year. In many years, southwest Idaho’s Owyhee River flows are so low that it’s virtually unrunnable-this year is a wonderful exception. As shown in this video by Idahoan Andrew Dunning, elite kayakers are already taking advantage of high flows on the North Fork of the Payette to experience its world-class rapids. And Idaho river outfitters and guides are prepping for an epic season across the state.
You don’t have to be on the river to experience the novelty of this year’s high flows. Just upstream from the town of Twin Falls, the Snake River’s Shoshone Falls is a sight to see-literally! More than 22,000 cubic feet/second are flowing over the falls. To put that in perspective, the median flow for this time of year is 3300 cfs and the lowest recorded is 358 cfs. I visited Shoshone Falls recently and noted license plates from CO, NV, OR, ID, WA, UT, MT, NB and WI. The word is out about the Niagra of the West.
How Long Will It All Last?
Federal, state and local water managers work together in times like these to try and protect communities from floods by steadily releasing water from reservoirs while also holding back enough to meet summer’s agricultural irrigation needs. In a perfect world, flooding is minimal and the higher than average-but less than flooding-flows will last all summer. Achieving that perfect balance is no easy feat, and I’ve heard more than one agency hydrologist say they’re not sleeping well at night these days.
As hard as it is to imagine right now, there is a realistic scenario in which the summer-long high flows wouldn’t pan out-all it would take is unseasonably high temperatures this spring. And considering the earth has broken high temperature records three years in a row that’s not as farfetched as you might think. High temps earlier than normal will mean the snow melts earlier than normal, which could result in serious flooding combined with low or no flows later in summer.
Why Does ICL Care About All of This?
The crux of my job as ICL’s water associate is to identify and advocate for ways to create healthier Idaho rivers-and keeping enough water in the rivers is an increasingly uphill battle. Every watershed is unique, but many of Idaho’s rivers are so manipulated by humans that periodic flooding such as we are experiencing now is the only time a river sees anything resembling healthy flows.
Shoshone Falls provides the starkest example. Way more often than not, a visit to Shoshone Falls is a visit to see one of the world’s tallest dry waterfalls. It is official state policy that zero flow in the river is the ideal flow at Shoshone Falls, as that would mean the water would all be put “to use” by the irrigated agricultural industry upstream of the falls.
Just last week I was in a meeting of water managers and irrigators who lamented the “water being wasted at Shoshone Falls.” And the Snake is not the only river in Idaho that some would prefer to see dry. Countless Idaho rivers and streams are managed so that its acceptable to completely dewater them, and virtually all our rivers are at risk of ultimately being managed that way.
Potential floods are concerning for people and communities who have built in floodplains. But floods also provide benefits to the environment and therefore to us all. Historically, they happen every few years and are a big part of why many of Idaho’s rivers are so phenomenal. Simply put, floods are critical to a river’s ability to act as a river. Floods redistribute sediment, helping river channels maintain their structure, creating habitat for fish and other wildlife, and depositing nutrient rich sediment on agricultural fields in the floodplain. In the long run, floods improve water quality. Without some flooding, over time we’ll lose virtually all of the ecological services our rivers provide.
ICL doesn’t believe water in a river is waste-we believe it is a river being a river. Periodic flooding plays a part in that. ICL works hard to ensure that sufficient water remains in Idaho’s rivers to allow them to do what rivers must do-because it’s ultimately good for all of us to keep our rivers healthy.
To learn more about how you can support ICL’s water and climate work, check out our It’s My ID! campaign.