As most of us in Reno already know – it is an extremely dry winter. What does this mean for the Truckee River, Lake Tahoe and Pyramid Lake? Likely, without a significant change in the overall precipitation pattern, Lake Tahoe will fall below its rim at 6,223 feet and no more water will flow to the Truckee from Tahoe. That means that all the water in the Truckee River will have to come from other tributaries – mostly from releases from reservoirs. The Federal Water Master, Chad Blanchard, told a TV news station, “We are basically out of water in those reservoirs at this time or very close to it. [The Truckee River flows] will be an absolute trickle but it will be much lower than people are used to.”
The Truckee River has had 14 mostly below to well below average years since 2000 and the current outlook is for continued dry conditions stretching into spring. [Only 2005, 2008, and 2011 saw well above average precipitation.] Cities and agriculture use up most of the river during low flow years leaving less water to maintain natural systems. Pyramid Lake’s surface elevation is well below its level in 2000. Pyramid Lake is natural end of the Truckee River, but we divert water from the Truckee for many uses – cities and towns, ranches and farms, and industry such as power plants. Currently, nearly 65 % of the water in the Truckee River you see flowing through the Truckee Meadows is diverted into the Newlands Project canal at Derby Dam. Water diverted there never reaches Pyramid lake and instead flows to the Carson River through the Truckee Canal. How many visitors to Lahontan Reservoir on the Carson River realize that the water entering the reservoir near the dam is actually from the Truckee River? Right now most of the water filling Lahontan is coming from the Truckee River not the Carson River (which was effectively dry at Lahontan most of the summer and well into the fall).
Water from the Truckee River, diverted into the Truckee Canal at Derby Dam, ends in Lahontan Reservoir on the Carson River. (D. Ghiglieri, January 2014)
Our use of water from all sources, including the Truckee River, depletes water for natural systems. Human uses take significant amounts of water directly from streams and the river leaving smaller amounts for Lakes and in-stream flows. Effectively, even in an average year, natural systems slide into drought conditions. In a drought, natural systems can simply disappear and the wildlife they would otherwise support disappear, too. We have made strides to keep some in-stream flows during droughts through the “Water Quality Agreement” that Reno and Sparks entered into in the 1990’s. That offers all of us a little hope that the Truckee won’t be dry this year. If 2015 is dry too, all bets are off.
January 17, 2014:
- Stampede Reservoir, CA on the Little Truckee River: 50% of capacity (113,000 acre-feet)
- Prosser Reservoir, CA on Prosser Creek: 22% of capacity (6,620 acre-feet)
- Boca Reservoir, CA on the Little Truckee River: 17% of capacity (6,882 acre-feet)
- Donner Lake, CA Storage: 34% capacity (3,270 acre-feet)
- Independence Lake, CA (Truckee Meadows Water Authority): 80% capacity (14,000 acre-feet)
- Lake Tahoe CA, NV: 6 inches above its natural rim at 6,223.55 feet of elevation currently in decline.
- Truckee River flow at the Vista Gauge (leaving Sparks): about 280 cubic-feet-per-second (CFS)
- Diverted Truckee River water in the Truckee Canal (heading to Lahontan Reservoir): about 180 CFS
- Truckee River flow at Nixon, Pyramid Lake Pauite Reservation: about 100 CFS
Water from the Truckee River enters Lahontan Reservoir: