Category Archives: Keep it flowing

Cities, towns, development, farms, ranches take water from the Truckee River – some years taking nearly its entire flow

Jul-Sept 2017 Temps up (way up)

How hot was it? Pretty hot.

The National Weather Service reports that Reno, NV – yup, right here in river city – set a new record for a 51 day stretch of 90 degree or higher temperatures shattering the previous record from just 7 years ago of a 35 day streak.

Overall, the summer had the highest average temperatures ever recorded for the area, too, 77.2 degrees – nearly 5 degrees above the long-term average. And, Reno sweated through a record 16 days of 100 degree or higher temperatures this summer.

Warm daytime temperatures are often taken in stride by most of us. Temperatures throughout the west and especially in Reno have been rising steadily for many years.  The RGJ noted that overall average temperatures have been steadily warming for the past 70 years.  The average minimum temperature increase means many more days of the year have temperatures above a killing frost resulting in a long growing season more often than in the past. These warmer temperatures impact the urban environment when people need to water earlier in the spring and later into the fall due to both warmer temperatures and the length of time with above freezing temperatures.

This summer California and Nevada during July-September showed a strong warming in both the maximum and minimum average daily temperatures. It isn’t much of a surprise to most of us, but the consequences are more need for irrigation outdoors.  The Truckee Meadows Water Authority (TMWA) spokesman said at a “Water Smart” forum last week, that the water purveyor hadn’t noticed any increase in water use due to a longer irrigation season in a response to a direct question. TMWA does not have information on water use per capita or by type on its website when reviewed for this article.

Check out the graphics on average minimum and maximum temperatures for Jul-Sept 2017 for the USA and the overall average temperatures (last graphic).

Related articles across the web

Truckee flows cut while Tahoe nearing maximum storage behind dam

The latest flows from Tahoe (as of 7/13/17) are a mere trickle compared to the flows of the previous 5 months. Flows over the past 4 days from the Tahoe Dam have dropped each day from 300 CFS on July 10th, 200 CFS on July 11, 170 CFS on July 13, and now 70 CFS on July 14. Lake Tahoe’s water surface elevation has not risen over the past week and stands currently 1.3 inches below its legal maximum of 6,229.1 feet. Does the cut in releases into the Truckee mean the Water Master must store that last 1.3 inches of runoff behind the Tahoe Dam?

The reservoirs on the Truckee River are all now essentially full. While there is still snow in the higher elevations, the low elevation snow pack is now gone reducing the amount of runoff in creeks and streams flowing into the Truckee and Tahoe. Current storage stands as follows:

Reservoir on Truckee River

Storage July 14, 2017 acre-feet

Capacity acre-feet

Percent Full

Lake Tahoe (Water Surface Elevation in feet AMSL)

6,228.99

6,229.10

99.9982%

Donner Lake

9,555

9,500

100.5789%

Independence Lake (owned by Truckee Meadows Water Authority)

17,588

17,300

101.6647%

Prosser Reservoir

24,499

29,840

82.1012%

Stampede Reservoir

226,394

226,500

99.9532%

Boca Reservoir

40,761

41,110

99.1511%

Note: Martis Reservoir on Martis Creek, a tributary to the Truckee River, is used for flood control and currently holds 890 acre-feet due to leakage
Reservoir on Carson River Storage July 14, 2017 Acre-feet Capacity Acre-feet Percent Full

Lahontan Reservoir

305,038

295,542

103.2131%

Lahontan Reservoir stores water diverted from the Truckee River by the Truckee-Carson Irrigation District via the Truckee Canal and the Carson River for the Newlands Project. Since mid-January diversions have been limited due to high flows on the Carson River with current diversions going to irrigation in the Fernley area and the Fallon “bench” lands portion of the Project but not to Lahontan Reservoir.

Pyramid Lake and Truckee River: home for wildlife

The lower Truckee River on the Pyramid Lake Paiute Reservation is home to many species of wildlife. In the mountains both west and east of Pyramid Lake live Bighorn sheep and mule deer, as well as thousands of migrating and nesting birds.

Caspian Tern at the lower Truckee River at Pyramid Lake

Caspian Tern at the lower Truckee River at Pyramid Lake

Pyramid Lake and the lower Truckee River are the only places in the world where you can find Cui-ui fish and the largest cutthroat trout – the Pyramid Lake strain. Anaho Island, a National Wildlife Refuge fully contained within the Pyramid Lake Paiute Reservation, is home to an American white pelican nesting colony along with nesting California gulls, double crested cormorants, snowy egrets, and others.

Pyramid Lake itself is also a home for birds nesting and raising their young. This year’s substantial flows on the Truckee River have created additional places for birds to nest. Western grebes and Clark’s grebes have built floating nests on shallow areas recently covered by Pyramid’s rising water level.  The nests require considerable attention of the nesting pairs to prevent the nests from being swamped by waves or raided by over-flying common ravens. The grebes make repeated trips to pick up floating vegetation and sticks to continually improve the nest and allow the eggs to hatch. Once hatched, the young birds can immediately take to a parents back or swim on their own. Bank swallows nest in holes in a steep slope such as those created by high flows along a river bank. High flow conditions this year opened up many new places for bank swallows along the Truckee River.

Changing Climate or Wet Year?

If the fish and wildlife dependent on the Truckee River and Pyramid Lake and Lake Tahoe could cheer, we’d certainly be hearing the shout-out because of this winter’s huge rain and snow events bringing near record river flows this spring. After such a long drought and long-term rain and snow deficit beginning in 2000, this year has been a celebrated event.

Is it just a wet year following a drought or are erratic swings in precipitation to be expected from Climate Change? Are having the driest year on record in 2014-15 and the wettest year on record in 2016-17 the pattern of a new “normal” for the western US?

Truckee River at Mayberry Park viewed from Steamboat Ditch Trail

This is a winter and spring of superlatives for Truckee River flows. Pyramid Lake has risen, so far, 9.1 feet since January 1, 2017 and on June 1 was at a water surface elevation 3,801.24 feet above sea-level. This is a tremendous benefit to the endangered cui-ui fish found only in Pyramid Lake as well as its huge Lahontan Cutthroat Trout that wow fishermen at 15 or even 20 pounds. In the last 20 years, the high water elevation measured at Pyramid Lake was 3,817.6 feet on August 17, 1999. Prior to the federal government’s 1905 Newlands irrigation project that diverted water to expand farmland in Lahontan Valley, Pyramid Lake was relatively stable at an elevation of about 3,875 feet.†

The Truckee River on June 8, 2017 flowed at 3,900 cubic-feet-per-second (CFS) or 5 times the long-term average flow on that date – higher flows only occurred once before in 1983 (which was a wet year preceeded by several wet years).

Lake Tahoe has gone from below its rim last October to rise more than 6 feet totalling 736,000 acre-feet of water with more still coming. On June 19, the water surface elevation of Lake Tahoe was just 4.8 inches below its legal maximum of 6,229.1 feet elevation. The result of the rainfall events and exceptional snowpack runoff has contributed to the large flows of the Truckee River from late winter into spring. Summer flows in the Truckee River will also be larger than seen in many years.

Another wet year could bring Pyramid Lake back to levels not seen since 1999 when Pyramid Lake’s water surface elevation was 16 feet higher than today. Flows in the Truckee River are typically higher in multiple wet years in a row when reservoirs are already full and water must be released from reservoirs like Lake Tahoe rather than stored. If the Sierra around Tahoe has a similar rain and snow-filled winter season for 2017-18, then all of the runoff would flow to Pyramid Lake resulting in a significant inflow increase to Pyramid and raising the water level of Pyramid Lake substantially more than we saw this year. But, if next winter is average or dry, then runoff to Pyramid will be substantially less and no bump in Pyramid’s water level will occur.

American White Pelicans hang out at the Truckee River delta at Pyramid Lake April 2017.

American White Pelicans hang out at the Truckee River delta at Pyramid Lake April 2017.

So, with wild swings in preciptation observed since 1997, what can we expect from the winter of 2017-18? How will climate change – read climate warming especially in the northern hemisphere – affect snowfall and rainfall that keeps the Truckee River flowing and water in our Lakes?

With President Trump’s withdrawal from the International Climate accord, it appears that, at least from the Federal Government, it is a reversal of positive action to protect the earth from the most disastrous effects of a warming world caused by burning fossil fuels. The new administration seems determined to rapidly increase use of fossil fuels and stop solar and wind and geothermal technologies from competing.

Click to see.

Each of us and individual states and businesses can, however, choose to reject returning to the coal-style economy of the last century which brings higher temperatures, increased evaporation and evapotranspiration, and is very likely part of the wild swings in weather world-wide, and especially concerning for the arid western US.

Meanwhile, NOAA reports that there is a 50-55% chance that there will be “neutral” conditions in the Pacific meaning no “el niño” or “la niña” is being forecast at this time. What does that mean for the upcoming winter weather? We’ll find out at the end of March 2018.

Expect the wild ride to continue.

† Under natural conditions and prior to the 1905 Newlands irrigation project, Pyramid Lake and Winnemucca Lake both received water from the Truckee River. When Pyramid Lake reached an elevation of around 3,880 feet, water would flow through a channel north of Chalk Bluff to Winnemucca Lake. Because of the Newlands irrigation project, Pyramid Lake steadily dropped and no water could flow to Winnemucca Lake. Winnemucca Lake, once a National Wildlife Refuge, dried up in 1940. Pyramid Lake is presently about 80 feet lower in elevation than its historic level. The channel to Winnemucca Lake is still visible from highway 447 as you go around Chalk Bluff. The Pyramid Lake people in the 1920s recorded the precipitous fall of Pyramid Lake by recording elevations on the famous Pyramid. The dates inscribed on the Pyramid show how quickly it shrank as diversions began. The dates of 1924, 25, 26, 27, and 28 are visible even today each showing the successive decline in the Lake’s elevation.

Pyramid Lake dates inscribed on Pyramid

Tahoe rising; releases to Truckee from Lake Tahoe fall

Lake Tahoe water surface elevation 05-09-2017

With warming temperatures and the recent rain, Lake Tahoe water surface elevation jumped 3.7 inches in just 7 days with a distinctly rising trend. Releases from Lake Tahoe Dam, controlled by the Federal Water Master, dropped over the past week to around 1,300 cubic-feet-per-second (CFS). The drop in releases from the Tahoe Dam could be to keep the overall flow in the river through Reno-Sparks below 6,000 CFS as flows from tributaries pour into the Truckee River from increasing snowmelt. Even with the reduction of flows from Tahoe, the Truckee River flow is still near 6,000 CFS at Farad, California.

Truckee River releases at Lake Tahoe 05-09-2017

Flows into Pyramid Lake continue to hover right around 6,000 CFS. Diversions to the Fernley division of the Newlands Project continue to be less than 100 CFS.

With ample snow still covering the upper elevations of the Sierra and Carson Range, high flows will continue for the next weeks on the Truckee River as well as the Carson and Walker Rivers.

Washoe Lake is on both sides of the US 395 freeway as of today. Given that last fall, there remained just a large water puddle in the middle of the larger south end, the turnaround is remarkable.

Washoe Lake at State Park, southeast side of the Lake looking to Slide Mountain in the Carson Range.