Author Archives: Dennis Ghiglieri

About Dennis Ghiglieri

My concern for the Truckee River grew over the years. It started with picking up trash and supporting better water quality. I helped create the "living river"plan with other citizens on the Community Flood Coalition; a plan to reduce flood impacts to infrastructure through river restoration and protection of the floodplain. I understand how critical the Truckee River is to the environment – and economy – of our entire region. I'm hoping that through these pages we can all understand our connection to the Truckee River and why we need to protect it.

Lake Tahoe: dry to wet to dry to wet, again

Truckee River flows from Lake Tahoe in this 2018 GoogleEarth view.

Extremes likely to continue

The water year 2022-2023 will certainly be a wet year. Lake Tahoe and the Truckee River basin both are near or above 200% of snow pack water content for this time of the year. The question is, how much of this exceptional snow pack and water will flow downstream to Pyramid Lake?

Lake Tahoe: critical for the Truckee River flows

Truckee River at Wingfield Park

Lake Tahoe is the beginning of the Truckee River. Over the millennia Lake Tahoe was a natural regulating reservoir. Today a dam constructed on the river artificially raises the level of the Lake and controls how much water from the Lake flows into the Truckee River. No water flows into the Truckee River unless the elevation of the water surface elevation of the Lake rises above the outlet’s rim at elevation 6,223 feet. The dam allows the level of the water in Lake Tahoe to rise 6.1 feet higher and store up to 740,000 acre-feet of water. The rise in the Lake’s water surface elevation is most obvious to us when stored water covers up a significant part of beaches such as Sand Harbor State Park or Zephyr Cove. The Federal Water Master determines the amount of water to release into the Truckee River at any given time. 

Today (3/29/23) as I write this, only 46 CFS (cubic-feet-per-second) flows out of Lake Tahoe through the gates of the dam and into the Truckee River. Under natural conditions at the Lake’s current water surface elevation of 6,225.4 ft (2.4 feet above its natural rim), much more water would be flowing into the Truckee River. The dam allows farmers and other downstream water users to delay flows into the Truckee River to better suit their needs.

Dams delay and reduce spring flows of the Truckee River

Fish and wildlife throughout the Truckee River basin evolved to take advantage of high spring time river flows that now are controlled by the 6 major dams on the river and its tributaries. Lake Tahoe is the largest storage reservoir on the river. Together, the reservoirs can store nearly 1.1 million acre-feet of water – or nearly two years of the average long-term flow volume of the Truckee River. In early March 2023 about 360,000 acre-feet of water was stored in the 6 reservoirs – most of it in Lake Tahoe. Once snow melt commences, the all the reservoirs will likely be filled as close to their capacity as possible.

From Dry to Wet to Dry to Wet?

Burn in Carson Range above Carson City
Burn near Lake Tahoe in the Carson Range early 2000s

Dry years or below “average” years since 2000 dominated the weather for much of the southwestern USA including California and Nevada. Well above average winters benefitting flows in rivers and storage in Lakes and reservoirs allow us all to breathe a sigh of relief hoping that the “drought is over”. Dry or drought conditions appear to be getting drier and perhaps wet conditions are likewise getting wetter. Extremes may be increasing on both ends. Climate change drives both very likely.

Lake Tahoe Elevation and Truckee River Cumulative Flow at the end of the water year

Above average or “wet” (water) years occurred in 2016-17 and 2018-19. Dry years occurred in 2019-20, 2020-21, and 2021-22. The graph shows that up to the middle of March 2023, Lake Tahoe has once again begun to rise. With a significant snowpack now at the end of March, it will likely continue to rise. What isn’t clear is how that will translate into flows for the Truckee River below the dam at Lake Tahoe.

The 5 year drought that proceeded the very wet 2016-17 water year (from October 1 to September 30) left Lake Tahoe nearly a foot below its rim. With significant rain and snow that year Lake Tahoe rapidly rose to near its maximum water surface elevation. Over 314,000 acre-feet of water flowed that year into the Truckee River and the following two years saw an additional 525,000 acre-feet of water. The next 2 years of drought and hot summers emptied Lake Tahoe’s stored water. 2021-22 water year started off wet, but the following January 2022 was the driest on record followed by very dry February and March. Lake Tahoe was quickly drained again.

However, this year the snowpack is nearly double average and colder weather has suppressed the snow melt. As of today, 163 inches of snow stands at Ward Creek on the west side of Lake Tahoe. That snow contains the equivalent of 70 inches of water – just under 6′ of water content. The official “end of winter” measurement of comes in 2 days.

Starting in mid-October 2023, Lake Tahoe fell below its outlet (rim) for just over 2 months. Atmospheric river rain and snowstorms rapidly raised its level by over two feet.

With the approach of April, below average temperatures are expected to persist for the next week or so with more snow also possible over the weekend. Presently, the watershed contains 226% of average snow water equivalent.

Under purely natural conditions all the water in Lake Tahoe above its rim flows into the Truckee River and downstream to Pyramid Lake each year. Pyramid Lake’s water surface elevation stands significantly below its historical level and well below it level in 2000.

How much of this year’s abundant snowpack’s water will flow to Pyramid Lake?

Drought Impacts Persist into Spring 2023

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

Precipitation for the 2022-2023 Water Year through March 20, 2023

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.)

Tahoe’s water surface elevation elevation over the past year

Flows into the Truckee River at Tahoe City, CA stop once the elevation of Lake Tahoe drops below 6,223 feet – indicated on this graph as “3.00”. Lake Tahoe has a large surface area and around 350,000 acre-feet of water evaporate from its surface each year. Its maximum elevation is set not to exceed 6,229.1 feet.

2023 Sees Big Snow Pack – so far

March came in like a lion with several continuous days of snow. January and February snows in the Carson Range and throughout the Sierra increased an already above-average snowpack for this time of the year to 179% in the Tahoe Basin and 169% in the Truckee Basin.

The welcome snow contrasts with the dry winters for the previous two winters. With climate change making ever hotter summers the Truckee River had low flows, Sierra reservoirs shrunk, and Lake Tahoe fell nearly a half-foot below its rim for 65 days last fall and early winter.

Atmospheric Rivers helped to build the snowpack

Lake Tahoe State Park at Spooner Lake Feb 22, 2023

Rain and then snow powered first by an “atmospheric river” and then a parade of January snow storms pushed the snowpack to over 150% in the Tahoe and Truckee Basin. Storms at the beginning and end of February continued to push the snowpack up and March is continuing the trend. As I write this, it is snowing lightly in Reno. (Another possible atmospheric river arriving in a couple of days could bring rain to lower elevation snowpack with a threat of increasing localized flooding possible.)

From nearly a half foot below its rim, Lake Tahoe today stands over two feet higher. With such a large snowpack yet to melt, Tahoe is set to rise considerably more. Likewise, reservoirs on the Truckee River system have storage available as evidenced by the following table of current levels.

Plenty of storage capacity remains in Truckee River Reservoirs

Reservoir NameStorage in Acre-feetCapacity in Acre-feetCurrent Storage %Remaining Storage in Acre-feetRemaining Capacity (%)
Independence (TMWA)13,59717,50077.7%3,90322.3%
Lake Tahoe
† Storage
Total361,2521,068,810 707,558 
March 8, 2023: Truckee River Upstream Storage

Where will this winter snowpack end up? March appears set to add more to the precipitation already received. The next storm system forecast is for rain at lower elevations below 7,000 feet to start.

Lake Tahoe from Mt Rose Highway Feb 22, 2023

The NRCS reports that “[a]s of March 1 the Reno Airport has seen 38.3 inches of snowfall through March 1 which is nearly twice normal for the entire winter.” The Airport has seen at least 4.5″ of snow fall since then.

Still, the total amount of precipitation from the winters of 1982-83 and 2016-17 exceeds this winter’s precipitation – so far.

† By court decree, the dam at Tahoe City, CA at the outlet to the Truckee River can raise the level of Lake Tahoe 6.1 feet to elevation 6,229.1 feet AMSL.

Drought persists: Dry January and February

Dry ground on Peavine Mtn

Deficit of rain and snow continues into March.

Hope for a “jubilant” January, a “fabulous” February, and a “miracle” March fell flat this year. The western US, including much of California and Nevada, faces another drought year. The Drought Monitor map shows the Sierra Nevada in “severe drought” along with all of western Nevada. Worse designations of “extreme” and “exceptional” drought categories are found in portions of 8 of the 9 western states.

Drought Monitor 3-8-2022
Drought Monitor 3-8-2022

Truckee River: low flows ahead for spring and summer

After the summer of 2021’s extreme fires and, in much of the west, unprecedented heat, December’s storms seemed to herald an above average water year in the offing for the Sierra. But a record breaking, dry January and February ended the hope that the 200% snow pack would persist. The ides of March has come and gone. Yet, the Sierra snowpack that supports the Truckee River is just 76 and 68 percent of average in the Truckee River and Tahoe watershed today. Lake Tahoe is just 12″ above its natural rim and the very real prospect of a continuing dry spring mean lower flows into the Truckee River below Tahoe City. The traditional April 1 peak snowpack measurement becomes less relevant as climate change warms temperatures winter and summer. The lack of storms in what should be the Sierra “wet season” stretches our multi-decadal drought for yet a further spring and summer.

Lake Tahoe elevation Jan'20 to Mar'22
As spring runoff approaches Tahoe’s surface elevation stands just 12″ above its rim.

Truckee River Trail – scenic and troubled

The Truckee River Trail through Reno attracts residents and visitors alike. The river environment can be a source of peace and rejuvenation. It is more than just a water supply for the cities; it is a true recreational resource providing a scenic trail throughout urban Reno and Sparks all along the clear, flowing waters of the Truckee River. The community has invested to make this trail a treasure for all.

Trouble in river city

The Truckee River Trail is also the default location for many of the area’s homeless and graffiti taggers. Many of us who advocated for creating and expanding the recreational trail along the river to connect the urban environment to the natural environment of the Truckee River never foresaw the extent to which the trail would become a literal semi-permanent campground with ever increasing graffiti tagging. People I’ve spoken to tell me they avoid the Truckee River trail downriver of Idlewild Park due to the urban troubles intruding into and taking over the natural environment with trash and camps and tagging. The encampments, when “cleared out” quickly return in the same or new locations. Some trash often remains scattered across the banks of the river – bottles, wrappers, bags, blankets, baskets, etc. – regardless whether the site is occupied by the campers or not.

Encampment along Truckee River Trail
Encampment along Truckee River Trail (Jan’18)

I’m revisiting the issue of encampments, trash and graffiti again in the hope that we can change our approach to keeping the river clean and stop pollution from the encampments. Right today there is not much reduction in the encampments, trash and graffiti that I observed and wrote about 3 years ago. Below are scenes along the Truckee River from downtown Reno to Greg Street taken in late September of last year. [I’ve digitally edited the graffiti so that it is not identifiable; this reduces the “in your face” aspect of the tags, but prevents advertising it.]

Truckee River Trail needs help

As the City Council’s and County Commissioner’s try to deal with the issue of homelessness, the Truckee River Trail impacts continue to mount. The river environment becomes an unfortunate camping ground and restroom for hundreds of people seeking temporary or permanent shelter along it. The issues that surround homelessness likely leads to much of the trash found along the river banks. The lack of regular pickup of trash and cleaning up discarded items of clothing, food containers, makeshift shelters also encourages graffiti taggers to add to the atmosphere of neglect and abandonment. An Insufficient number and desperately inadequate restroom facilities throughout the urban trail portion contribute to the pollution and inhumane conditions.

Can our Council’s and Commissioner’s focus their attention to the daily negative impacts to the Truckee River – throughout its urban reach – by funding new staff for clean up efforts? How about if the community funded the installation of more restrooms? And clean and refresh those restrooms 3 or more times per day and keep them open at least from 6AM to 10PM everyday?

The Truckee River is the community’s lifeline for our water supply but so much more. It deserves more attention from our elected leaders to fund clean up crews on a daily basis – not just when a homeless “clear out” is in the works.