Reclamation to Measure Springs below Yellowtail Dam
Flows in the Bighorn River will be significantly reduced over a five-day period during October to facilitate the measurement of springs below Yellowtail Dam. Releases from the Yellowtail Afterbay Dam will be reduced in increments beginning at 7:00 am on October 17, so that by early in the morning of October 21 a flow rate of 400 cubic feet per second (cfs) will be obtained.
A flow of 400 cfs will result in a drop in river stage of approximately three feet from the current level. The 400 cfs flow rate will be maintained for approximately five and one half hours while the springs that flow into the Afterbay Reservoir are measured. At approximately 12:30 pm on October 21, releases from the Afterbay Dam to the Bighorn River will be incrementally increased until a flow rate of approximately 3,000 cfs is reestablished.
“Measuring the flow from the springs is a necessary and critical part of inspections we perform at Yellowtail on a three year cycle. Unfortunately, we have to evacuate the Afterbay Reservoir to take the measurements, and that means there is a period of time when flows in the Bighorn River are very low”, said Tom Tauscher, Reclamation’s Yellowtail Facility Manager. Tauscher added, “I wish we had some other way to perform the measurements, but we simply don’t have that luxury. We have however, worked closely with Montana Fish, Wildlife & Parks both on the timing of the tests and on the increments of our flow fluctuations, to minimize impacts to the river fishery.”
Fishermen and other recreationists using the river are cautioned that low flows during this period may make it difficult to float the river.
