ALAMOSA — With the Rio Grande Basin at 150 percent of average snowpack on Wednesday, forecasters are expecting a healthy stream flow this year on the Rio Grande.
The Division of Water Resources Division 3 office is currently anticipating an annual index flow on the Rio Grande of 800,000 acre feet, or about 123 percent of average, Pat McDermott reported to the Rio Grande Water Users Association members during their annual meeting on Wednesday.
The obligation on an 800,000-acre-foot flow to downstream states under the Rio Grande Compact would be 32 percent or 257,000 acre feet, McDermott explained. Taking all factors into account, to meet that requirement irrigators would be facing a 25 percent curtailment, he added. If the Rio Grande produces 850,000 acre feet, the obligation would rise to 34 percent or 292,000 acre feet, and irrigators would be looking at a 28 percent curtailment.
The greater the flow of the river, the higher percentage must be sent downstream. Once the river hits 900,000 acre feet, “you start paying one for one,” McDermott explained.
However, with a better runoff this year, “the hope is this year to get juniors into priority,” McDermott said.
He explained that not all of the runoff would reach the stream since the basin had a “hole” to fill from 2018, the fourth driest year on record with a flow on the Rio Grande of 280,000 acre feet or 46 percent of the long-term average. Colorado only owed 71,000 acre feet to downstream states and ended the year with about a 3,300-acre foot credit.
SNOTEL measurements throughout the Rio Grande Basin right now are very encouraging, McDermott said. “This year we have intermediate and high snow in abundance — north, south, east and west.”
For example, in the Upper Rio Grande Basin at Beartown, at an elevation of 11,600, the snowpack is 158 percent of average, 236 percent at Cochetopa Pass (elevation 10,020) and 159 percent of average at the Wolf Creek Summit (elevation 11,000), while the SNOTEL site at the Cumbres Trestle (elevation 10,040) is a healthy 131 percent of average and the Upper Rio Grande (elevation 9,400) is a whopping 248 percent of average.
“The snow is excellent,” McDermott said.
On both sides of the basin, snowpack is well above average, with Medano Pass, for example, boasting 191 percent of average on Wednesday.
McDermott said the water division is pleased with Chief District/Water Judge Pattie Swift’s Friday ruling on the groundwater regulations and irrigation season. While the irrigation season dates were policy in the past, they are now court ordered, with the presumptive irrigation season set from April 1 to November 1.
The Rio Grande Water Users Association on Wednesday voted to turn on their water on April 1.