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.

Drought conditions in northwestern Nevada, Nov. 26th, 2014 and outlook

Drought conditions have changed significantly in some parts of Nevada, but not so much in others.  As you can see from the side-by-side comparison of drought severity in Nevada, provided by the U.S. Drought Monitor (see http://bit.ly/1xU7GW2), the crescent-shaped area of Exceptional Drought (depicted as D4 on the map, in a brownish-red) has more than doubled, now covering approximately 12% of Nevada, up from slightly more than 5%, estimated on January 7, 2014.  Remember that the D4 designation indicates likely long-term ecological change due to exceptionally dry conditions.  At the same time, the eastern half of the state has seen a slight improvement from severe to moderate drought conditions.  This has been reflected in comments from ranchers in Nevada's eastern counties, who note that rangelands have had plentiful forage in some areas.  Drought conditions are not uniform in the state and vary significantly for many reasons. 



Weather forecasters remain uncertain about our chances of having a good Sierra snowpack as we transition to winter.  The Mt. Rose SNOTEL site reports an accumulated total of 2.4 inches of liquid precipitation since the beginning of the water year (Oct. 1, 2014).  This includes about 0.7 inches that fell as snow.  In contrast, the accumulations of precipitation, as snow and total , in water year 2012 were 1.7 and 5.2 inches--slightly more than double the observed to date.

Overall, the water year has not had a promising start in the western portion of the Great Basin, with less than 10--30% of normal recorded at our weather stations, depending upon location.  This means that snowpacks in the Sierra Mountains are well short of normal relative to this date in other years. 

 

Dipping into the reserves

The discharge graph for the USGS gaging station just behind the City of Reno's solid waste transfer station (left) illustrates the loss of flow from Lake Tahoe, which occurred shortly after July 28th.  Note that the hydrograph has discharge presented on a log scale--shortly after July 30th flow decreased dramatically in the Truckee, reaching a minimum of about 60 cubic feet per second around mid-day, August 3rd.  Fortunately, several storms (see the graph below from a weather station located at the University of Nevada have increased flow for short periods of time (see precipitation record below). However, without more rain we will likely see a return to the low levels observed before our monsoon-driven storms brought some relief. 

Drought status in northern Nevada, July 30 2014

As the illustration below shows, the size of the regions of Nevada that are included in the four categories of drought severity (moderate severe, exceptional and extreme) have remained about the same and in the same locations for more than year.  However, northern Nevada residents are beginning to see the effects of several dry years, especially if they the right to withdraw water from surface water supplies such as the Truckee River.  As of the end of July, two sources of water for the Truckee will dwindle (Lake Tahoe and Boca Reservoir), which means that flows in the Truckee will also decrease.  This means that downstream users, such as the Truckee Meadows Water Authority, will begin releasing storage from other sources in a stages to meet their needs downstream.  This also has the benefit of maintaining some flow in the Truckee.  The Truckee Meadows Water Authority has a plan for meeting water demand by using different sources upstream, including Donner Lake.  Their plan relies partially on voluntary conservation (http://bit.ly/1oMc1q2).  The plan is designed to meet system demand for the remainder of the summer months--a critical period that corresponds with peak water use associated with irrigation and lawn maintenance. 

One of the consequences of this shortage is that many of the ditches that divert Truckee River water for what were historically agricultural purposes will be dry for the rest of the irrigation season.  This will have a big impact on those who use the water to irrigate pastures and crops.