The Deschutes was once a very stable river. Before Wickiup Dam was completed in 1949, the Deschutes River exhibited very consistent seasonal flows. It’s common for most rivers to experience high flows with the onset of spring rains and melting snow and very low flows by the end of the summer. These rivers may experience flow fluctuations of 80-90% in a year. But the Deschutes is different.
The Deschutes River is believed to be the largest spring-fed river in the U.S. The water in the river originates high in the Cascade Mountains, where 10-20 feet of snow accumulate each winter. In the spring, the snowmelt seeps directly into porous volcanic rock rather than running off the surface in creeks and streams. Hydrologists say that 80% of the river’s flow comes from groundwater rather than surface water. The stable flow in the Deschutes is caused by an extensive network of springs that pour into the river throughout the year.
The construction of Wickiup Dam dramatically changed the hydrograph of the Deschutes. What was once a river with very stable flows is now a river with high fluctuation. We see flood-level flows every spring while the river is dewatered every winter.
There are grave consequences of this flow regime imposed by dam operation. Before Wickiup’s construction, the more stable historic flows of the Deschutes supported abundant wetlands with a rich diversity of aquatic plant and animal species. The floodplains were full of sedges teeming with amphibians, fish, birds, beaver, otter, and many others. Over the past 70 years, the high flows released from Wickiup Reservoir flooded the wetlands to such an extent that the aquatic vegetation could not survive. Today, where there were once rich wetlands, we find barren mudflats. These high, scouring flows also stripped away the willows, dogwoods, and other riparian vegetation needed to anchor and stabilize the river’s banks. The massive erosion resulting from these forces dumped sediment on spawning gravels, clouding the river.
A YEAR OF DROUGHT and an inadequate plan
2021 is destined to be one of the driest years in the past three decades. But, if you look at the upper Deschutes today, it’s easy to misunderstand the extent of the drought. As the river flows through Bend at a whopping 1,600 cubic feet per second, who could be concerned about drought while the river rages? Despite the dry year, it is business as usual for Bend and Redmond’s irrigation districts using water that is not essential for irrigation needs.
The water being wasted across Central Oregon is tragic. Tens of thousands of acres are being irrigated inefficiently, in many cases simply to maintain a water right. As a result, the farmers who do require this water to support their livelihoods, along with the fish and wildlife who depend on a healthy river, bear the brunt of water shortages.
The Habitat Conservation Plan (HCP) submitted last year to U.S. Fish & Wildlife by irrigation districts represented an opportunity to address some of the severe problems in the Upper Deschutes River below Wickiup Dam. It was a chance to improve flows in the river.
Unfortunately, in the approved plan, higher winter flows come too late and are insufficient to support ecological health, according to USFWS’ own research. Spotted frogs, for instance, need water levels between 600-900 cubic feet per second (cfs) to support winter habitat. Unfortunately, under the HCP, only 400 cfs is required. Even that insufficient amount is not guaranteed for another 13-15 years. It is a hard truth to face, but it is distinctly possible that the Oregon Spotted Frog will not survive in the river that long.
In the summer, we see the other side of the coin, with flood-level flows. The U.S. Fish and Wildlife Service recognizes that “capping” summer flows is critical but does not impose this measure for 13 more years. We cannot wait that long to restore the river.
There are feasible, cost-effective solutions for putting more water instream in the winter (and lowering summer flows) much sooner. In the proposed plan, USFWS simply deferred to the irrigation districts' plan, one that relies on securing hundreds of millions of dollars of taxpayer funds for canal piping and doesn’t require water users to conserve water despite evidence of widespread waste of water in districts with senior water rights. We need a better plan to restore the Deschutes.
Contact Tod Heisler for more information and ways to get involved.
