Bend Bulletin - Deschutes River natural flow starting to turn the corner after historic lows
After several years of intense drought, Central Oregon has experienced two successive winters with above-average snowpack.
But despite these wetter winters, the so-called natural flow in the Deschutes River is struggling to resume average flow levels.
In June the natural flow in the Deschutes averaged 1,184 cubic feet per second, according to Jeremy Giffin, watermaster for the Deschutes Basin. It’s an improvement from two years ago but still well below the typical rate of 1,400 to 1,500 cfs.
Natural flow reflects the amount of water in the river if there were no diversions or storage facilities altering flows. For the Deschutes, records of natural flow began in 1938. The lowest recorded natural flow for June was 1,027, recorded in 2022.
“Over the last 10 years, we have seen the natural flow in the Deschutes drop to historically low levels,” said Giffin.
The most recent high for natural flow in the Deschutes River occurred in 2017 when the August flow was 1,494 cfs. The figure coincides with a massive winter snowpack in the Cascades that collapsed several roofs in Bend.
While the Deschutes River’s natural flow is low this year compared to historical data, it is slightly higher compared to the recent years of drought — it was the second highest for June in the last five years.
Natural flow and storage matter a lot for Central Oregon’s agricultural community in times of drought. While the region was briefly drought-free in June, Deschutes, Jefferson and Crook counties have all slipped back into moderate drought, according to the U.S. Drought Monitor.
Reservoir reliance
With the river running about 25% below its historic averages, irrigation districts in Central Oregon have been relying more heavily on reservoirs to supply water to patrons. This has led to historically low levels in Prineville, Wickiup and Crescent Lake reservoirs.
But improved natural flow has given reservoirs a break this year — all are at similar or slightly higher levels compared to a year ago.
“Looking at storage levels along with the natural flow I would say we are starting to see signs that the surface water supplies are doing a little better than the previous three to four years,” said Giffin. “We are still very low but better than the most recent drought years.”
Irrigation districts have curtailed deliveries of water to patrons in recent years to counter the low flows and depleted reservoirs, forcing farmers to cut back on the acreage they plant, sometimes by half.
During the drought years, some districts also used up their water allotments before the season ended, leaving farmers with a shortened growing season.
Craig Horrell, general manager for Central Oregon Irrigation District, the largest in the region by number of patrons, said the district remains in recovery mode, but improved natural flow should ease conditions compared to the drought years.
“(Central Oregon Irrigation District) will likely make it to the end of the season with full natural flow,” said Horrell. “This is better than the last few years when we had to curtail to 70% delivery in July.”
Changing the narrative
The increased natural flow is already changing the narrative of the water shortages, said Josh Bailey, manager for the North Unit Irrigation District, which serves farmers in agriculture-heavy Jefferson County.
“(North Unit Irrigation District) did benefit earlier this season from the higher natural flow,” said Bailey. “We did not have to pull as much from storage early on as in the last few years.”
Bailey adds that if natural flow levels hold up over the next few weeks, Arnold and Lone Pine irrigation districts may be able to operate without using stored water. If that comes to pass, North Unit will have access to more stored water in Wickiup Reservoir.
Bailey said results from the 2024 planting season are mixed so far. Yields have been good so far this year, but prices for most crops grown in Jefferson County are down. And the reductions continue to reverberate.
“Farmers have to fallow 40 to 50% of their ground to get enough water to produce a crop on the other half,” said Bailey. “This, coupled with low commodity prices, higher labor, fuel, fertilizer, seed, and other costs is a recipe for tough times.”
