The Fluid Dynamic

Regulated Deficit Irrigation

by Curt Burnett on August 21, 2009

Goldhamer calls the week-long study the greatest professional experience and research accomplishment of his 30-year water management career.

“Aerial Imagery Future of Water Management” Western Farm Press August 5, 2009

I’ve been reading about new methods for tightly controlling irrigation to minimize water use and salt buildup in the soil. Here’s a brief description of regulated deficit irrigation (RDI) from the website of the California Agricultural Water Stewardship Initiative:

Deficit (or regulated deficit) irrigation can maximize water use efficiency by maintaining or increasing yields per unit of irrigation water applied. In deficit irrigation, the crop is exposed to a certain level of water stress for certain periods or throughout the whole growing season. The expectation is that yield reduction will be insignificant compared to the benefits gained from decreasing water use. However, deficit irrigation may only work for certain crops and the grower must have prior knowledge of crop yield responses to deficit irrigation. One of the greatest obstacles to implementing deficit irrigation is the wide range of crops that one grower may manage in any given season in California. More research on deficit irrigation forspecific crops and soils is needed to ensure guidelines for implementation are successful.

One of the challenges encountered in managing RDI is that plant stress needs to be monitored to avoid long-term crop damage. A piece in the Western Farm Press reports on a recent joint study done by David Goldhamer of UC Davis and scientists from the University of Cordoba in Spain. Dr. Goldhamer has been researching plant stress measurement for some time, and he was intrigued by that ability of the Spanish drone aircraft and their specialized infrared cameras to measure canopy temperatures. This general approach has been attempted in the past using satellites, but the low-flying drones made possible a degree of resolution which has previously eluded researchers.

I think that we can expect to see tremendous progress in the next few years in the efficiency of irrigation. As water becomes more valuable and land damage through overapplication of water becomes more obvious, technological advances like RDI will become increasingly attractive.

Peter Gleick in Stockholm

by Curt Burnett on August 19, 2009

I’m regularly approached by scientists and policymakers here asking me if it is could really be true that we do not measure and manage all groundwater in California. It is. We don’t. And outside of California it is well understood that this means it is simply impossible to have a truly sustainable water system. It’s like having a bank account without know who is taking money out or how much they are taking.

Peter Gleick, president of the Pacific Institute, writing from the Stockholm Water Conference

The Stockholm Water Conference is underway, and I’m very sorry to be missing it. Maybe next year….But we have a summary report from Dr. Water himself, Peter Gleick. As I mentioned in yesterday’s post, one of the things that I appreciate about Dr. Gleick is that he values irrigated agriculture, and wants to see it survive and prosper in the US. But at the same time he realizes that without sustainable water practices irrigation in many arid or semiarid locations has no future, which puts him at odds with those who take a shorter-term view.

I was talking with someone the other day about water as a finite resource that that needs to be carefully managed, and he seemed puzzled. He asked, “Can’t we just bring it in from other places?” And the answer is, well, yes, to a certain point and at a certain cost and provided whoever is using it in the other place doesn’t object. And if all else fails, for potable water there’s always seawater to be desalinated. But for irrigation that’s really not a realistic option. Which leaves…careful use of what we have.

More With Less?

by Curt Burnett on August 17, 2009

Vegetables…produce substantially more revenue per unit land or water: vegetables account for only 16% of the irrigated acreage but use 10% of the applied water and generate 39% of California’s crop revenue.

from More With Less: Agricultural Water Conservation and Efficiency in California, a Special Focus on the Delta by H. Cooley, J. Christian-Smith, and P. Gleick

Over the weekend I read a 67-page report from the Pacific Institute which discusses some very practical measures which would allow California agriculture (and by implication the Central Valley) to survive and thrive on less water. What I most appreciate about this study is the concern it shows for the economic health of agriculture and the livelihoods of farmers and their business partners. The other positive is that its recommendations are not extreme, and in most cases match trends that are underway, driven by ongoing shortage.

The report has a number of legislative recommendations aimed at doing away with some perverse incentives to waste water. It goes into water law (California has one of those hybrid Riparian/Appropriation systems discussed in one of my water law posts) and recommends some minor changes. One of these is a classic change already made in many states faced with water shortages:

Define instream flow as a beneficial use in California

“Beneficial use” is a legal term in an approprative system, and it determines what constitutes a legitimate appropriation which establishes and maintains a water right. What this means is that leaving the water in a river in order to maintain an adequate volume of flow is a legitimate use which can keep a water right alive. (In Australia this use of water has been given the name “conveyance”, and is an important feature of that country’s new approach to water law.)

The concrete suggestions for water saving are as follows:

  • Modest crop shifting
  • Smart irrigation scheduling
  • Advanced irrigation management
  • Efficient irrigation technology

The thing to note about these approaches is that all of them are already happening at some level, so this is not a fantasy approach.

Fish vs. Farms?

by Curt Burnett on August 14, 2009

Before 1850, there were probably 1 million to 2 million steelhead spawning in Central Valley waterways. Most recently, there were 3,628 spawners, according to a 2005 study.

From the Stockton Record, June 14, 2009

After a couple of days in the Central Valley and a few hours spent researching the history and current situation around the drought, I watched a Youtube video of the Sean Hannity broadcast on the same situation. I knew that the broadcast had taken place because they were scheduled to visit the Westlands Water District later in the same day we were there. Sean gets very exercised about the outrage of farms being shut down to save “baitfish”, the delta smelt, which play some role in the current limitations on pumping Sacramento River Delta water into the west side of the Central Valley.

I’m not sure what Hannity’s motivations are (although they don’t appear to be to educate the public on a complex situation). But saying that the water problems of the Central Valley are due to lunatic environmentalists trying to save the delta smelt is like saying that General Motors went bankrupt due to Congress passing fuel economy laws. There may be some slight connection but there’s a whole lot more to the story than that.

This brings back to mind the talk given by Professor Mike Young at the Irrigation Water Conference. He used the term “strife” to describe the kind of pointless, futile conflict that took place in Australia in the early stages of their long water emergency. It seems to me that the current situation in the Central Valley lends itself to the kind of solution he was talking about, where everyone involved realizes that the battles aren’t going to make any more water, and they sit down to arrive at solutions together.

The environmentalists concerned about the ecological health of the Sacramento Delta aren’t going to go away. The cities who also crave Delta water aren’t going away either. And it wouldn’t be good for the country if agriculture went away in the Central Valley. So what can be done?

It seems to me that the most urgent item on the to-do list is already in process, but needs to be stepped up in a water-short environment. We visited a huge orchard complex further south in the valley which has used nothing but drip for many years, in conjunction with all of the best practices for optimizing irrigation. They go to great lengths to not use one more drop of water than necessary. This not only saves water, but more importantly it helps slow the degradation of the soil due to salinization. On the other hand, we stopped at one tomato farm to look at some of their equipment, and immediately noticed a leak of 60 gpm or so rapidly growing a pool on the ground. The equipment looked very poorly maintained, and it wasn’t hard to imagine that such leaks are a frequent occurrence. This kind of waste was likely insignificant when the Bureau of Reclamation was providing 100% or even 50% of nominal contracted water, but at 10% it’s not going to work for long.

If we again look to Australia for a picture of the future, it may be that Central Valley growers will have to evaluate their crops, and in some cases switch to the less water-intensive varieties. On the municipal side, valley cities like Stockton are clearly going to have to tighten up their water and wastewater practices, including more extensive water reuse for landscape irrigation.

One plan for increasing available irrigation water while at the same time protecting the delta involves raising the dam that forms Lake Shasta. Not surprisingly, many of the people who live in the vicinity of the lake have an opinion about that. The reality is that the era of grand irrigation projects and new dam construction has passed, and these days every action to secure more water has its inevitable reaction.

Sign of the Times

by Curt Burnett on August 12, 2009

No Water = No Jobs, No Food, No Future

Sign on I-5 near Fresno

Driving up I-5 yesterday along the western edge of the Central Valley was a fascinating experience for a water wonk. About every half mile there was a sign fastened to a fence, a farm trailer positioned for maximum visibility, or a building. “Congress Created Dustbowl” was the most popular. This was typically in dusty, fallow fields, presumably due to the absence of irrigation water.

I got to talk with some folks in operations at the Westlands Water District. This is the largest irrigation district in the US, and certainly among the hardest hit by the water situation here in the Central Valley. They have resigned themselves to the apparent reality that 50% of the original Bureau of Reclamation water allotment (from the start of the Central Valley Project) is the new “normal”. However they and the growers were caught off guard by the 10% (up from 0% originally proposed early in the summer) that they are actually getting. They and the growers are piecing together sufficient water for some crops in some places through limited transfers from other areas plus unsustainable groundwater pumping. We saw some some bumper crops of tomatoes ripening in the fields, as well as healthy-looking almond and pecan trees. But as always, the pain is spread unevenly. Some farmers are doing moderately well, others are being ruined.

I was impressed with the folks at Westlands. It doesn’t appear to me that they have ever taken the water they manage for granted. They had universal metering long before other districts, and they seem to have a good grasp of how much water is being used by whom, which believe it or not is unusual. They are hoping to obtain stimulus money (decision pending) to further upgrade their monitoring and control ability to nearly realtime (daily), through telemetry. Of course, all of this is to some degree an act of faith. It assumes there will be at least some water in the future, which is by no means certain.

California Here I Come

by Curt Burnett on August 10, 2009

The District has experienced a decrease in its water supply since the drought that began in 1987. Drought conditions as well as environmental regulations have led the Bureau of Reclamation to dramatically reduce the amount of water it delivers to Westlands, to the point where today, the District can expect to receive only about 50 percent of its contractual water supply in an average water year.

from the Westlands Irrigation District website

I’m headed out this evening for Fresno, bound for the Westlands Water District. I hope to get an opportunity to see firsthand some of the issues facing this largest irrigation district in the US. The Westlands website has a good summary history of the district, particularly its relationship with the Bureau of Reclamation. Whatever interpretation one may eventually make of some of the more controversial facts about the Westlands’ situation, it’s hard not to be concerned about the future of this highly-productive agricultural area and its contribution to the nation’s food supply.

There are two main problems facing the Westlands’ roughly 600,000 acres of irrigated farmland. The obvious one is an immediate shortage of water, the other is a surplus of water. Both are common to areas of irrigated farmland. The surplus comes in the form of runoff, which has apparently been a problem from early on. Inadequate drainage led to a buildup of saline groundwater, which in some places is only ten feet below the surface.

Many areas of irrigated farmland have been rendered unusable by salt buildup in the soil, both in modern and historic times. The Westlands’ situation is apparently further complicated by the presence of other elements in the irrigation water, such as selenium and boron.

I’ll pick up all the information that I can and post more in the next few days.

Still More Water War

by Curt Burnett on August 7, 2009

While the judge’s ruling is more far-reaching than we anticipated, it is not entirely unexpected. ….Now that the legal question of Lake Lanier’s usage has been clarified, it is UCR’s hope that all stakeholders will get out of court and get to the solutions of how to manage this finite resource to the benefit of all who depend upon it, upstream and downstream.

from the website of the Upper Chattahoochee Riverkeeper

I’m back in Seattle now, but I can’t quite let go of the tri-state water war I left behind in Atlanta. It’s an intriguing case for many reasons. One of them is that at one time it appeared to be a model for cooperative settling of interstate water disputes. Legal battle between Georgia and Florida/Alabama was joined in about 1990, and then in 1997 there was what appeared to be a giant step toward resolution. The parties signed two agreements, one for each of the affected river basins, the Apalachicola/Chattahoochee/Flint (ACF) and the Alabama/Coosa/Talapoosa (ACT). These agreements were then ratified by Congress.

While the compacts didn’t settle the details of tri-state water use, they did create a detailed framework for creating a sharing system, with deadlines to keep things moving. Most unfortunately, the deadlines passed in 2003/2004 without said sharing system in place, throwing the case back into the courts and leading to the Federal Court ruling by judge Paul Magnuson this July 17. And as the judge described it, for Atlanta the ruling if left unchanged will be “draconian”. He allowed three years before it takes effect so that Congress can change the Corps of Engineers mandate if it so chooses.

Which brings up another interesting aspect of the whole situation. In many respects this is a water war between greater metropolitan Atlanta and Alabama/Florida. Without the massive withdrawals that Atlanta metro came over time to make from Lake Lanier, this quarrel likely woudn’t have come about.

Last evening I was thumbing through the Biennial Water Report 2008-2009 (edited by the ubiquitous Peter Gleick), and happened onto a piece on urban water use in three example cities, Atlanta, Seattle, and Las Vegas. Since I live in Seattle and had just returned from Atlanta (and was glad not to be in Las Vegas in August) I had to read it and study the statistics. One great thing about the usage stats is that they were broken down into indoor and outdoor use, allowing the separation of true domestic use and home landscape irrigation.

Not surprisingly, Las Vegas led the way in daily per capita use, at around 170 gallons, with about 70 going to irrigation, 100 to indoor use. Seattle had the lowest overall consumption at around 75 gallons, with very little going for irrigation. Atlanta had the highest indoor consumption, at around 110 gallons per person, plus around (surprisingly little) 15 for irrigation.

During the recent drought, Atlanta was apparently able to get average daily per capita use under 100 gallons, including irrigation. However, when the drought ended this spring watering restrictions were lifted and there are already signs that use is bouncing back.

As major cities go, Atlanta is rather constrained in water sources. Groundwater access is difficult due to the nature of the underlying rock formations, and the city itself is on relatively high ground. The Chattahoochee and Coosa rivers have been its main water source as it grew by leaps and bounds to around four million (metro area).

So one way that many observers portray the situation is that an overly-indulgent Army Corps of Engineers (custodian of the the dam that created Lake Lanier from the Chattahoochee) enabled Atlanta’s uncontrolled and somewhat unplanned sprawl by allowing ever-increasing withdrawals from the river system with little regard for the downstream users. Alabama and Florida had to go to court to stop the growth of the withdrawals.

It’s odd that a state which receives 50″ of rain a year would be involved in a pitched water battle, but that’s the reality. One can only wonder what the eventual tri-state water war in the desert Southwest (Arizona/Nevada/California) is going to look like. The three southeastern states could set a pattern for cooperative conservation and rational sharing, but given the history so far the prognosis isn’t good.

Tri-state Water War (con’t)

by Curt Burnett on August 5, 2009

“Florida recognizes that a solution must include equitable sharing of adversity.”

-from a letter sent to Secretary of the Interior Ken Salazar by Florida Governor Charlie Crist

There’s a great summary of the history of the tri-state water war on the site One of the links there, from the Atlanta Journal Constitution, covers a threat from a state legislator to move the annual Georgia-Florida football game in retaliation for Georgia’s loss in the July 17 court ruling. Now that’s a serious conflict!

Interestingly, this all comes after the drought that severely depleted Lake Lanier has officially ended with a particularly wet season this past spring (although the lake still stands nine feet below normal).

Also interesting is that Governor Sonny Perdue today had a meeting with representatives of other towns downstream of Atlanta, in an effort to form a unified front in the water wars. Georgia cities like Columbus and LaGrange which are farther down the Chattahoochee are concerned that their interests will be overshadowed by those of Atlanta. In some ways their sympathies might be more with those of, say, Florida in receiving the leftovers from Atlanta’s withdrawals.

The battle now moves to Congress. It’s hard to think that Washington DC is the best place to work out complicated water-sharing issues, but that’s how it is at the moment. Reviewing the history of the conflict, you can see that various federal agencies have stepped in at one time or another to try to help settle the war, and it has been in and out of Congress more than once. I think though that until the three parties somehow become motivated to hammer out a workable resolution among themselves there will be little progress.

Maybe it will take another, longer or deeper drought? Like the one in Australia?

Tri-State Water War

by Curt Burnett on August 4, 2009

ALBANY – Gov. Sonny Perdue will hold a meeting here Thursday to brief those in attendance about a recent federal court ruling that leaves Georgia’s future rights to the Chattahoochee River and Lake Lanier up to Congress.

Albany Herald, August 4 2009

I’m currently in Georgia, having come from Alabama yesterday. These two states along with Florida are the combatants in what has come to be called the “Tri-state water war”. This legal battle has contested Alabama and Florida against Georgia, which takes much of its Chattahoochee River water upstream of the other two states. Alabama wants to be sure that it has enough river water to cool some of its power generation processes, and Florida needs water near the mouth of the river to protect wildlife.

There was a key court ruling just over two weeks ago which was a major landmark in the ongoing legal combat between the states. The court ruled that Atlanta could no longer take water from Lake Lanier, one of the city’s most important sources, without permission from Congress. The reason is that the dam which created Lake Lanier was a federal project whose original stated purpose was to generate hydroelectric power, not create a reservoir for water extraction.

Georgia has been fairly agressive overall in promoting water conservation in irrigation (much of which is located in southwest Georgia and relies on Floridian Aquifer groundwater). It was one of the earliest states to mandate irrigation water metering, which is a key first step in reducing irrigation usage – as the old saying goes “you can’t control what you can’t measure”. Recently though the spotlight has been on urban use as Atlanta’s needs slowly lowered the level in Lake Lanier during intermittent drought years.

I’ll be writing more on this fascinating interstate water conflict in the near future, including the history of the two compacts that were created in an attempt to settle the issue.

Riparian Reasonableness

by Curt Burnett on July 31, 2009

“Under the riparian doctrine rights attach to riparian land, i.e., land bordering on a natural stream or lake, by virtue of its location”

Water Law, 3d Ed. D.H. Getches “Nature of Riparian Rights”

Twenty-nine states (primarily Eastern) follow the riparian approach to water rights. The fundamental doctrine that water rights derive from ownership of land which is on the river bank or lakeshore dates back to European and especially English law. Early American settlers brought over the common law concepts and further developed them, particularly around the key concept of “reasonable use”. This is the main limitation on riparian rights. Not only must the water use itself be reasonable (however defined), it must not injure the reasonable use of other riparians.

As with beneficial use, discussed in the last post, the range of reasonable uses is broad. However, some uses are more readily accepted under law as reasonable than others. So-called “natural” uses, which include domestic consumption and garden irrigation, are generally preferred to “artificial” uses such as industry, mining, or agricultural irrigation. Some of the criteria used to determine reasonableness are:

  • Suitability to the body of water
  • Economic value
  • Social value
  • Potential for harm to society
  • Protection of other existing users

Most states which use the riparian doctrine also limit water rights through a permit system. Permits typically are restrictive with regard to the nature of the use, the volume or rate of flow that can be taken, and the location of diversion from the body of water.

One key difference between riparian and appropriation-based rights is the the latter is a fundamentally “use it or lose it” system, ie the beneficial use must continue in order to retain the right. Since riparian rights derive from ownership of waterfront land, they typically continue whether exercised or not. (The one caveat is that permits once granted may lapse if not used.)

On the face of it, appropriation and riparian systems seem radically2009 different in key respects:

  • Use it or lose it vs. perpetuity
  • Not tied to land ownership vs. deriving from riparian ownership
  • Senior rights dominate vs. all rightholders share

It’s interesting then that ten states have hybrid systems which however uneasily try to combine the two systems. I’ll take a stab at describing the typical hybrid system in a near-future post.