Focus on Bend: DROUGHT: The glass lower than half empty made even worse with a June heatwave

             Everybody is talking about it, the weather that is.
            The first week of June began chilly as some nightly temperatures dropped into the 30s and days barely made it out of the 50s. And several days were marked with heavier rain and higher humidity.
            Then came a dramatic change, as the final week of the month brought Bend’s hottest day on record June 30 at 107 degrees, preceded in the previous two days by 102 and 104 readings with heat advisories daily going into the July 4^th holiday.
            Early July also saw much of the center of Oregon from the California line to Bend and Deschutes County rated either in “extreme” of “exceptional” drought, the latter being the federal Natural Resource and Conservation Service’s most hazardous parched category.

            Several newer wildfires broke out after a spectacular band of thunder and lightning cells moved across the region the final week of June. Together with larger fires in the Warm Springs area north of Bend and in northern California, Bend’s “smoke season” has gotten an early start.
            The continuing drought exacerated by a heatwave have forced regional irrigation districts to cut back water distribution from the Deschutes as natural flows continue to drop.
            On July 2 the Central Oregon Irrigation District, which manages senior water rights for 45,000 acres in the basin, announced it would be cutting back distribution to member irrigators.
            “The flows in the Deschutes River are continuing to drop and with that the COID delivery rates must decrease,” COID management informed members in a June 18 notice posted on its website.
            “Currently we are at a 65-70% delivery rate in our system. The river flows are being closely monitored and we will keep you updated as the flows and the COID deliveries decrease.”
            The COID notice said the district would begin providing 100 cubic feet per second (cfs) of its entitled senior rights to the North Unit Irrigation District, Arnold and Lone Pine districts that manage junior water rights in the basin.
            Already the North Unit had begun major reductions of water flowing to its members, who grow 55% of the region’s most productive cash crops on nearly 60,000 acres in Jefferson County north of Bend.
           The level of Wickiup Reservoir, which stores water for the North Unit is at all time lows for this time of year at 18% of capacity. On July 4 that translated to only 33,157 acre feet, 54% less than at this time in 2020, also a drought year, and 74% less than average.
    Note in the real time "Hydromet" teacup graphic available from the US Bureau of Reclamation that Crane Prairie Reservoir, which impounds water for COID, is in the best shape of any reservoir in the region. That reflects COID's standing as a senior water rights holder in the basin.

            In a July 1 announcement on its website the NUID manager began with a dire observation:
            “It pains me to write this letter, as I am fully aware of the difficult situation that we find ourselves in,” began general manager Josh Bailey.
            The announcement then continued to inform irrigators that in an emergency meeting June 30 the board of directors had approved another reduction of water distribution. That follows an earlier ramping down only days earlier on June 21.
            The latest NUID reduction emphasizes the dramatic and accelerating basin conditions, contradicting the district's early predictions that it hoped to maintain a 1 acre-foot distribution of its Deschutes River rights and .50 acres for water from the Crooked River throughout the season.

            In its earlier June cutback, the district reduced distribution to .90 acre foot per acre (af/pa) for the Deschutes water right and 0.40 ac/pa for the Crooked River impoundment at Haystack Reservoir in Jefferson County. Starting July 3, the distribution decreases to 0.80 ac/pa and 0.50 respectively.
            The goal, Bailey wrote, is to reduce immediate system demand and, “extend the available water through the end of August.”
            Although difficult to quantify, the drain on water availability in the greater Deschutes watershed is attributed to a confluence of several other factors joining drought conditions that have existed for several years with escalating and detrimental effect.
            For the past several irrigation years irrigators have been bound by terms of a Habitat Conservation Plan, negotiated by the districts, federal agencies, conservation groups and other stakeholders. The HCP agreement regulates river flows to protect the Oregon spotted frog, listed on the federal Endangered Species Act.

Equipment sits idle as fields dry out

            Together with lower snowpacks, the requirement that extra water be released into the river system at certain times in the frog’s life cycle has resulted in some loss of storage in area reservoirs.
             Even with cooperation among COID, NUID and the other smaller basin irrigation districts there is the overarching issue of balance between senior and junior water rights holders, one that exists throughout the structure of western water law.
            In most western states water rights dating back to the 1800s are based on the doctrine of prior appropriation, simply translated as “first in time, first in line.”
            In Central Oregon, the water rights aggregated through the Central Oregon Irrigation District in the Bend area were recorded and used on the land ahead of those implemented later by the neighboring farmers and ranchers to the north in Jefferson County.
            The paradox emerges when the North Unit providing nurturing water for typically higher value crop production has a lesser claim to the resource than COID, with fewer cash crops.
            In some cases, smaller operations are put in a position of growing hay or alfalfa in order to maintain the lower taxes on land zoned for exclusive farm use (EFU). Also a factor is the “beneficial use” requirement that a water right must be used at least one of the past consecutive five years, giving rise to the warning to “use it or lose it.”
            Irrigators in districts who do not plan to grow crops in a given year have the option to place to temporarily return their rights to improve river flows, or to effectively lease it to others in their district. But thus far few appear to have made that decision this season.
            COID’s gesture to release 100 cfs of its water right to benefit NUID users is no doubt welcome but will likely provide little significant relief for Jefferson County growers.
            Already many have either scaled back this year’s crops by fallowing some fields, or entirely thrown in the towel for the growing season. Some say that even trying to plant and maintain non-cash cover crops to staunch erosion will be too costly.

Measuring irrigation water: From cubic foot per second to acre feet

   It may be easier to understand how much water is used for irrigation by doing the calculations, starting with a cubic foot per second, or cfs, diversion.
    A cubic foot per second is the amount of water that would pass a given point in one second, or7.48 gallons. An acre foot is the amount of water needed to cover one acre to a depth of onefoot.
   In one hour, a 1 cfs diversion would cover an acre of land with one inch of water. In one day or 24 hours, then, 1 cfs would cover one acre with water two-feet deep—or 2 acre feet of water.
   Therefore, 2 acre feet per day is equal to a 1 cfs irrigation diversion.A 1 cfs irrigation diversion would result in 448.8 gallons in one minute (usually rounded to 450gallons per minute, or gpm). That would amount to 26,928 gallons in an hour, 648,000 in a dayand 236,520,000 gallons in a year.