“Inflows across the [Upper Colorado River] Basin, top to bottom are well below average. In fact, we’re setting records for what is in the streams today,” Kanzer said. “The numbers in the statistics are startling.”
Low inflows into Lake Powell have broken records in the last 12 months. The six month period between April to December 2020 was the driest period on record, and the months September 2020, October 2020 and December 2020 were the driest respective months on record in terms of inflow into Lake Powell, Kanzer said.
“Right now, again we are tracking to be one of the four or five driest years for inflow into Lake Powell,” he said.
Current operational forecasts into the basin’s largest reservoirs, lakes Powell and Mead, indicate that low water levels could trigger Drought Contingency Plan actions in both the Lower and Upper Colorado River Basin. If the level of Lake Powell is projected to fall below 3,535 feet in elevation by October 2022 — which is currently within the worst-case scenario forecast — it would activate the Upper Basin Drought Contingency Plan. This would trigger coordinated releases into Lake Powell from Flaming Gorge Reservoir and other upstream reservoirs to protect reservoir levels and maintain power generation at Glen Canyon Dam. Under the most-probable forecast, Lake Mead is expected to fall below 1,075 feet in elevation later this year. If so, this would push the Lower Basin into Tier 1 shortage under the drought contingency plan, which requires Arizona, Nevada and Mexico to further reduce their use of water from Lake Mead.
Closer to home in the River District, Colorado’s largest reservoir, Blue Mesa Reservoir, is not expected to fill this summer, possibly reaching only 73% of its capacity by July. Although it is still early, other important reservoirs, including Taylor Park, Ridgway, Granby and Green Mountain reservoirs also may not fill to normal levels this year, according to operational projections.