Where does Nevada's water come from?

John Cobourn

In early June 2015, Reno’s KNRV News Channel 4 aired a story which quoted me as saying that storing rain water from home downspouts in barrels for later use on the landscape is illegal in Nevada. This is true, though this is rarely enforced. In the next few days, over 60 people commented online about the ”ridiculous” nature of this story. The strong reaction made me realize that some Nevadans do not understand Nevada’s water supply nor the laws and regulations that govern it. In times of drought, this is an important topic to learn about.

Nevada’s water supply is the surface water available for use from streams, lakes and reservoirs plus 

Carson River floodplain from Kingsbury Grade

the groundwater from wells. It is replenished each year by variable amounts of precipitation, and it is depleted each year by evaporation, transpiration by plants, and consumptive (evaporative) uses by humans. In terms of climate, Nevada is the driest state in the nation.

In the current drought (see Livingwithdrought.com for more information, and the final report from the Nevada Drought Forum (available soon (December, 2015) at http://drought.nv.gov/), our surface water supplies are much lower than average due to decreased winter snowpack.  The groundwater in aquifers in many places is being used more rapidly than it is replenished by precipitation. In some agricultural regions, farmers are using more “supplemental water rights” from wells to grow thirsty crops like alfalfa—Nevada’s primary crop. In some valleys, the water tables are dropping.



The Carson River sustains agriculture, wildlife habitat and
rangeland along its course, from the Sierra Mountains
to the terminus in the Carson Sink. 

Water in Nevada is used as follows: About 80% of water is used for irrigated agriculture. Public supply for municipal and industrial use accounts for around 13% of water use and mining uses about 7%.

All surface and ground water in Nevada belong to the people of the State. Entities within the State can use that water if they own ”water rights” for use of a specific quantity of water in a particular place for a specific “beneficial use” such as irrigating a certain number of acres of alfalfa.

Residents cannot capture and store precipitation for later use unless they own a water right to put the water to beneficial use. Water law is based on the appropriation doctrine of “First in time—First in right.” In times of drought, senior rights owners can use all of their water before junior owners get to use any. Water law is described in Nevada Revised Statutes 533 and 534, and further defined by court cases and court decrees.

Water law and the water supply in Nevada are complicated. In future blogs, I will explain some of the facts in this article in more detail. It is a fascinating field of study that is part of Nevada’s rich frontier history.

The Power of the Watershed Approach for floodplain management

The Power of the Watershed Approach for floodplain management

by John Cobourn, Extension Water Specialist, University of Nevada Cooperative Extension

One truism often repeated is that droughts end with major floods.  Although every major flood may not be the end of a drought, some of Nevada's river systems have had significant flooding, leading to extensive and long lasting damage (http://pubs.usgs.gov/fs/1997/0182/report.pdf).

I have said that community water issues can be best understood in the context of the whole watershed. I also stated that on the Carson River in Nevada, the Carson Water Subconservancy District (CWSD) sponsors a community watershed group called the Carson River Coalition (CRC). It views all issues in the watershed in terms of integrated watershed management (IWM). This approach says problems with water quality, water supply, fish and wildlife habitat and floodplain management should be addressed in an integrated fashion.

Through a consensus process, the CRC has designated its most important single issue, the Main Message of the Coalition, to be protecting natural floodplains from urban development. (www.unce.unr.edu/publications/files/nr/2004/fs0471.pdf) This is a good example of the power of the watershed approach. Urban development on low-lying river floodplains puts the infrastructure built there at risk of damage from the very large floods that occur every fifteen years or so.  It also converts valuable agricultural land to pavement and rooftops, and it destroys wildlife habitat.

After large floods cause damage to homes or businesses, communities generally build levees along the river channel to protect infrastructure. After a few cycles of larger floods, higher levees and more development, the river could be put in an extremely expensive concrete-lined ditch, like the Los Angeles River.  The wildlife habitat will be lost, and recharge of groundwater aquifers will be reduced. The water quality will often be that of urban stormwater runoff, which tends to be poor.

Since everything in a watershed is interconnected, the CRC does not want to solve a flooding problem in ways that would create water quality or wildlife habitat problems. To preserve the natural functions and values of the river and its floodplain, they recommend using floodplains for agriculture, parks and other open space uses. Keep residences and businesses out of the floodplain, and there will be fewer flooding problems. The CRC’s recommendations for floodplain management can be viewed in the Carson River Watershed Regional Floodplain Management Plan (http://www.cwsd.org/wp-content/uploads/2014/07/FinalDraftfloodplainplan7-08.pdf)

Walker River flooding in 1997 devastated this section of
Route 395 in California, leading to years of road repair and

reconstruction. Photo from
http://monosheriff.org/sheriff/page/emergency-services
 

Learn more about Nevada’s flood hazards at www.Nevadafloods.org. Nevada’s Flood Awareness Week runs from November 1-7, 2015.

Watersheds and why they are important

Contributed by John Cobourn,
Area Water Specialist,
University of Nevada Cooperative Extension





Tau-Gu,Chief of the Paiutes and John Wesley
Powell overlooking the Virgin River, 1873



John Wesley Powell, the first director of the US Geological Survey and the first man to lead a boat expedition down the Grand Canyon, proposed that all political boundaries in the American West should be established along watershed divides. Powell believed that watersheds—also known as basins--are natural units of political and economic community. Powell’s proposal was not adopted.

In the American Southwest, the major watersheds are the Colorado River Basin, the Great Basin (with no outlet to the ocean), the Sacramento and San Joaquin watersheds feeding the Central Valley of California, and the watersheds along the Pacific coastline of California. Within the Great Basin in Nevada, there are four major sub-watersheds, the basins of the Truckee, Carson, Walker and Humboldt River systems.

To explain the importance of the watershed concept, let’s 

The Carson River watershed, shown in light green, flowing
northeast from the Sierra Mountains in California to

the Carson sink in Nevada

look at the Carson River Watershed, which originates at the crest of the Sierra Nevada and flows in two principal forks (East and West Forks) eastward into the Carson Valley, past Minden and Gardnerville, then through Carson City, Nevada’s state capital, and then down through Lyon County and past Dayton to the Lahontan Reservoir. The water is stored in the reservoir for use each summer in the rich alfalfa farming area of Fallon in Churchill County. The reservoir and its water distribution system, known as the Newlands Project, were built by the Federal Bureau of Reclamation in the early twentieth century to “make the desert bloom.”

The State of Nevada created a water resources management agency for the Carson River known as the Carson Water Subconservancy District (CWSD) in 1959. The story of the Carson River Watershed is told by the CWSD Website (www.cwsd.org) and by many publications such as the Carson River Watershed Map (www.unce.unr.edu/publications/files/ag/2003/sp0302.pdf). In 1998, a citizens and interagency watershed management group was formed—called the Carson River Coalition (CRC). Abiding by the principles of Integrated Watershed Management, the CRC attempts to consider and evaluate all issues of water quality, water supply, floodplain management and fish and wildlife habitat in an integrated fashion. Each of these key values within a watershed is connected to each of the others. 

In times of drought, the residents of major watersheds in Nevada are affected differently. The geography, groundwater quality, water rights and Court Decrees are different in each watershed. People suffer in different ways. More about these water supply issues will appear in the next blog. For more information about our drought see www.livingwithdrought.com and www.unce.unr.edu. 

Join the Water Conversation

John Cobourn, Area Water Specialist

University of Nevada Cooperative Extension. 

In my first blog post, I noted that the Western Governors Association’s (WGA) Drought Forum has urged citizens to join the conversation about drought and water in the West. I plan to contribute to that conversation with blogs on facts and ideas regarding “Water in the Southwest.” Look for this and other materials on www.Livingwithdrought.com and www.unce.unr.edu. 

Some of the numerous topics that we could discuss include watersheds, water supply, ground water, water pollution, floodplain management, water rights, irrigation water, water transfers, etc. While some states are asking people to cut home water use, the dialogue about water needs to be much more comprehensive. Our future depends on it. Water supply shapes how we live and work in our landscapes--see the "before" and "after" photos of the Rye Patch Reservoir, below.  This is a major stock of water from the lower Humboldt River and has not delivered water to irrigators in several years.  

The Conversation needs to be more pervasive than a mere blog. The Western Governors' Association (WGA) says we need “open dialogue and information sharing.” See http://westgov.org/images/2015_Drought_Forum_Report_for_website.pdf for the final report from this year long effort led by Nevada's Governor Brian Sandoval.  People in communities in the southwest should convene forums, write articles, create ballot initiatives and engage public and elected officials in the conversation. In this blog, I will try to add relevant information and to pose questions for communities to ponder.

When people talk about water, they often cite Mark Twain, who quipped that “Whiskey’s for drinking; water’s for fighting over.” In the arid southwest, people sometimes disagree about uses and management of water. Some people have strong opinions and may occasionally become emotional in responding to the statements of others. This is especially true when water shortages have profound effects on rural areas, where agriculture, including cattle ranching, is a major industry and way of life. 

To communicate about something as fundamental and important to all as water, we need to govern our emotions.  We need to strive for a meaningful conversation. That means communicating respectfully and listening closely. We should be hard on problems but easy on people. Discuss your interests and those of others rather than simply sticking to a rigid “position.” In a win-win solution, everybody gets their most important interests met.

Rye Patch Reservoir on the Humboldt River

in 2009, when water stored behind Rye Patch Dam

flowed through the regional network of

irrigation canals.

In short, this blog offers facts, ideas, reports and questions about water issues in the southwest. It can be seen as part of a larger regional conversation. I will rarely evaluate specific products. You do not need to respond to these blog posts. If you do, please be courteous and thoughtful. That way, your ideas will contribute to our understanding and ability to deal with important water issues.

Same view of Rye Patch Reservoir in 2013. 

Water levels in the reservoir were below the spillway,

meaning that farmers downstream received no irrigation water.

Water in Nevada in Changing Times

Contributed by John Cobourn, State Water Specialist, University of Nevada Cooperative Extension (check www.Livingwithdrought.com for information about strategies for coping with drought and www.unce.unr.edu for information about Nevada Cooperative Extension). 

Drought monitor from Sept. 22, 2015 shows slightly more than half of
Nevada remains in Extreme to Exceptional Drought

 

The Western Governors Association Drought Forum Report was released on June 23, 2015 (http://www.westgov.org/drought-forum). Under the leadership of Nevada Governor Brian Sandoval, the Forum proposed strategies for responding to droughts in the western United States. The Governors recommend open dialog and information sharing about water and how to be resilient to droughts.

Now is the time, if there ever was a time, for a sustained conversation about water in Nevada and the Southwestern United States. The climate of the Southwest is generally dry, with recurring droughts and floods. It is also a region of continuing rapid population growth. In 2015, after the fourth consecutive year of severe drought in Nevada and California, citizens want to know how our society and economy will be able to withstand another year (or years) of drought.

One good way to understand water issues is to place them in the context of watershed management. Nevada’s watersheds capture precipitation in the form of rain or snow, store it in soils, lakes and underground aquifers, then transmit it downstream to agricultural communities and to cities. The watersheds that support our water supply must be respected and protected from abuse. We rely on healthy, well-managed watersheds for our way of life. More about this in upcoming blogs.

In this blog, I intend to contribute factual information and analysis to “The Conversation” about water in the Southwest. As a Hydrologist with twenty seven years of experience in watershed management, I have worked on floodplain management, drought planning for farmers, and water quality best management practices for residential and small business properties. These issues are not well-understood by the general public, but they should be.

I invite readers to join The Conversation. Here is a passage from the Western Governors’ Drought Forum Report: “Citizen awareness is critical to the success of any drought or conservation measure,” said Cassandra Joseph, Senior Deputy Attorney General for Government and Natural Resources in Nevada. “It is difficult to achieve, but it is absolutely imperative that the general public understands the importance of water resource management.”

 

Living with drought: is the drought over now?

Our state climatologist, Dr. Doug Boyle, reports that every storm prompts questions about whether we are no longer in drought conditions.  As of May 19, the U.S. Drought Monitor map of conditions in Nevada indicated that the storms have had little effect (see below), even though we have recorded slightly less than 0.5 inches for the month of May at the Washoe Evapotranspiration project's station on the University of Nevada campus (see http://www.washoeet.dri.edu/washoeEt.html for this excellent resource). 

Other data on the Washoe ET site provide a more complete picture of why a half an inch of rain in a week did little to change the picture.  Our estimated potential evapotranspiration (the amount of water returned to the atmosphere by the combined evaporation and by plant transpiration) for May is 4.0 inches, 8 times more than what has come so far as rainfall.  That means that even if our storms are high duration, low intensity storms, the soil is dry because evapotranspiration moves a lot of water from the soil profile into the atmosphere.  It would take a lot of rainy days to replenish soil moisture enough to change the National Drought Monitor Map. 

For more information about our drought and how to cope with it, visit www.LivingwithDrought.com.  Good resource for a wide range of interests. 

Living with Drought, Nevada

The Federal Water Master's office for the Truckee River Operating agreement (http://www.troa.net/) issues water supply forecasts near the middle of each month.  The Truckee River's upstream reserves have declined steadily since February, 2015, with a well below normal snowpack and reservoirs, including Lake Tahoe, which are likely to yield nothing as a short irrigation season begins.  As an example, compare the projections from January and April 2015 for water surface elevation and releases from Lake Tahoe for calendar year 2015. 

January's projections indicated a 50% chance that the water surface elevations would be at the natural rim for about a month (mid-May to mid-June). This is important because Tahoe, as a large natural reservoir, sustains flow in the upper Truckee River (Tahoe City to Truckee).  By April 15th, projections indicated that the probability of having water surface elevation reach the national rim dropped to about 30%, for less than a month.  Accordingly, the projected releases from the lake dropped from a peak release of about 15,000 acre feet in mid-July (with a 10% probability of happening) to a peak of about 250 acre feet in mid-July (with a 30% chance of happening). 

This means overall a low lake level, low flows in the upper Truckee, and diminished water supplies all the way through the Truckee River system for the summer and the critical irrigation season.  The consequences?  Limited access for boat launching in the lake and in upstream storage reservoirs, no recreational opportunities in the river, early termination of irrigation supplies, even in the ditches that have senior water rights.  Overall, lots of effects that won't be noticeable right away, but will be easy to see by the end of the summer of 2015. 

For more information on strategies for coping with water shortage see www.LivingwithDrought.com.  
More, later.