On January 31 the Deschutes River Conservancy announced that they had secured funding from Intel Corporation to help with their middle Deschutes summer water leasing program. Without the DRC’s various efforts, including the leasing program, the middle Deschutes below Bend would be virtually dry in the summer. Additional funding for the leasing program is welcome news but requires some context.
Flows in the Deschutes above Bend are controlled by irrigation districts who withhold water to fill reservoirs in the winter and release water in the summer which is then diverted into a series of irrigation canals. The last major diversion is located at the North Canal Dam in Bend just upriver from the Riverhouse. During irrigation season the Deschutes below this dam is reduced to a relative trickle, dramatically damaging the ecosystem for fish and wildlife.
The DRC’s water leasing program is an attempt to increase summer flows below the dam to 250 cfs, a target they are halfway towards reaching. The leasing program uses donated funds to purchase water from irrigators willing to temporarily lease those rights back to the river. While ongoing funding is certainly an issue, the primary impediment to success is that some irrigation districts have policies that constrain the amount of water allowed to transferred back to the river.
It is also important to note that this water is only returned during irrigation season, from mid-April until in mid-October. During the winter most of the water in the Deschutes is withheld to fill Crane Prairie, Wickiup, and Crescent Lake. Winter flows in the Deschutes below these reservoirs are from releases required for endangered species along with flows from Fall River and Spring River which meet the Deschutes above Bend.
Unfortunately, winter flows have sudden, extreme fluctuations when irrigation districts periodically divert water from the river for “stock runs” to fill their ponds. These large withdrawals have significant impact, stranding fish (and kayakers), exposing the river bed to potentially freezing temperatures which kill plants and the aquatic insects that fish feed on, generating silt which chokes spawning beds, etc. These periods of low flow may only last a day or two but the damage is done. Just like us, fish need to breathe all day long, every day, not just most of the time.
Also troubling is the recent public admission by the irrigation districts that they don’t need to have these extreme fluctuations in the winter. At a recent meeting the districts stated they could currently deliver a minimum of 250 cfs to the middle Deschutes in the winter, even during stock runs. They could do this with existing infrastructure via operational modifications. It is a mystery why they don’t do this already.
The chart below shows flows for the current water year. The dips in the blue line indicate stock runs. You can also see that average summer flows are well below the 250 cfs target set by the DRC. Note that the historic natural water level in the Deschutes below Bend prior to irrigation withdrawals was close to 900 cfs, a flow that would be fairly constant year round.
While the water in the Deschutes is controlled by irrigation districts it is owned by the public. Oregon’s Public Trust Doctrine states that public resources be used for the benefit of the public. To that end the districts should allow individual irrigators to lease water back to the river if they so desire. The districts should also manage stock runs to have less dramatic impact on the river, as they have said they are able to do.