Despite above average snowpack
Reno and environs continue to see above average snow and rain. The rain and snow over the last several months would seem to indicate the drought conditions over the past two years are gone or nearly so. Sure enough drought conditions have lessened (even gone away in some places), but still persist in most of Nevada, a big chunk of northern California and, unexpectedly, most or some portion of each of the other western states.
Copious snowfall in the Sierra Nevada benefits the water outlook for this summer and for the flows of western Nevada rivers – the Truckee, Carson, and Walker. River flows on the Truckee River remained below flood levels, in part, due to the below average temperatures which keep the snowpack from melting and the storage available in the upstream reservoirs.
Lake Tahoe below its rim
Lake Tahoe was 5″ below its rim this past November 30 due to the past 2 years of drought. Since December 1, 2022 Tahoe’s water surface elevation rose 2.7 feet (32.5″). How much will Tahoe’s storage increase once snow melt commences? Spring temperatures and soil conditions and wind will all play a part in determining how much of the water stored in the snowpack flows into the Lake. One thing for sure, cold temperatures experienced this year in Reno and much of the far west are unlike our more recent warm winters (more on this later).
Drought conditions persist but improve
Drought conditions still stretch across most of Nevada (70%). However, significant improvement since last October resulted from the storms which began hitting the region over the past 5 months. Drought conditions covered 96% of Nevada at the beginning of the water year. Severe (D2) to Exceptional (D4) Drought occurred in 48% of the state. Currently, the highest categories – D3 to D4 – cover only slightly more than 2% and Severe Drought (D2) found in about 14% – a hopeful change for the conditions this spring and summer.
Drought conditions shown on the map occur even though the precipitation since last October is over 100% in most of northern Nevada. If wet conditions continue through the spring and into the beginning of summer, additional improvement may be expected.
Precipitation exceeds the 30 year average
Large snowpacks this year in the Lake Tahoe and Truckee Basin are welcome to help alleviate the drought conditions experienced throughout the west and our region since 2000. Reservoir storage for the Truckee River should improve significantly. However, the western US drought may be more of a more systemic occurrence influenced significantly by Climate Change. Nowhere is this more obvious than on the Colorado River Reservoirs Lake Mead and Lake Powell currently 28% and 23% full, respectively. Conditions for those reservoirs are not expected to improve despite more than 100% snowpack in the Rocky Mountains.
(Watch for a discussion later for how storage affects the overall health of the Truckee River system.)