Lake Mead from the window seat

Anyone who flies in an airplane and doesn’t spend most of his time looking out the window wastes his money.

– Marc Reisner, Cadillac Desert

Lake Mead from the air, flying into Las Vegas

Lake Mead from the air, flying into Las Vegas

My Southwest flight into Las Vegas was nearly empty (a rarity these days), so I had my choice of window seats on either side of the plane and the chance to move back and forth. But the pilot’s descent into Las Vegas was literally directly over Hoover Dam, so we couldn’t see it.

Nice view of all the Lower Basin’s water in Lake Mead, though, just waiting for someone at the Bureau of Reclamation to turn the spigot and send it downstream to grow lettuce or water a golf course. Looks like plenty of water to me!

Decoupling in water, Albuquerque style

Total water use in Albuquerque for the first 11 months of 2015 is down 6 percent from the same period in 2014, according to the Albuquerque Bernalillo County Water Utility Authority’s latest pumping and diversions report. Indoor use (as measured indirectly by comparing this year’s sewage treatment plant outfall to last year’s) is essentially unchanged, suggesting that the bulk of the savings are in outdoor watering.

Since the sewage treatment outfall is being returned to the system for full use downstream (ecosystem, agriculture, downstream communities, and Rio Grande Compact deliveries to Texas), that means an estimated decrease in consumptive use (the outdoor use that really matters because the water cannot be returned to the system for reuse by others) is down a remarkable 13.5 percent.

Weather is clearly a factor here. Albuquerque precipitation is 15 percent above average for the calendar year. But also worth noting is that we have seen year after year of decrease, in both wet years and dry years, so community water users are doing something more complicated here than simply watering less when it’s raining.

Decoupling in water, Los Angeles style

Fortunately, the L.A. Department of Water and Power has come a long way in the last 20 years. For a time, says McQuilken, managers balked at the idea that conservation and recycling could replace the Mono Basin losses. But since then, the utility has become one of the country’s most progressive. Take water conservation. Simple measures like encouraging customers to rip out lawns and install low-flow toilets have made a stunning difference. Despite the addition of a million residents, Los Angeles uses less water today than it did nearly half a century ago. (emphasis added)

J. Madeleine Nash reporting in High Country News

New paper clarifies what satellite data is telling us about Colorado River Basin groundwater pumping

A paper out yesterday adds new detail to the picture provided by satellite groundwater observations of the Colorado River Basin, arguing that groundwater depletions from human pumping are not as large as suggested by previous research.

The paper, Hydrologic implications of GRACE satellite data in the Colorado River Basin published in Water Resources Research (behind paywall, sorry), points to large changes in soil moisture as a result of drought, rather than human groundwater pumping, as the explanation for a significant portion of water losses identified by NASA GRACE satellite observations. This is especially true in the Upper Colorado River Basin. In the Lower Basin, the picture is more complex, with some groundwater losses in parts of rural Arizona, balanced by stable or rising aquifers in the state’s heavily populated and heavily farmed central valleys.

The paper provides a significantly different picture than a widely publicized paper by Stephanie Castle, Jay Famiglietti and colleagues at UC Irvine and NASA last year that attributed the changes in water balance in the Colorado River Basin to unmanaged groundwater pumping by human water users.

The new analysis, from a team led by Bridget R. Scanlon at UT Austin and the USGS, uses new methodology for analyzing the GRACE satellite data in an attempt to better characterize the spatial detail of the missing water. GRACE, which infers changes in the mass of water above and below the earth’s surface by measuring changes in the gravitational tug on overflying satellites, has become a powerful tool for measuring groundwater depletion, especially in areas where the pumping is huge,

Data from the German-NASA GRACE satellites highlights groundwater depletion hotspots in the United States. CREDIT: CAROLINE DE LINAGE/UNIV. OF CALIFORNIA, IRVINE, Science magazine

Data from the German-NASA GRACE satellites highlights groundwater depletion hotspots in the United States. CREDIT: CAROLINE DE LINAGE/UNIV. OF CALIFORNIA, IRVINE, Science magazine

like California’s Central Valley and the Ogallala Aquifer in the U.S. midwest. But in areas where groundwater pumping is smaller, like the Colorado River Basin, the problem is trickier. GRACE provides an overall estimate of the change in the water mass balance, and then secondary calculations are needed to apportion how much of that change is groundwater, surface water, and the thin layer of soil moisture in between. Those secondary calculations introduce significant uncertainties into the results.

The Scanlon et al. paper is an attempt to resolve contradictions between the Castle et al. paper and work by other researchers. In particular, the new paper notes, the rates of depletion in the earlier paper were significantly larger in the Upper Basin than could be accounted for by known areas of groundwater pumping as identified by the U.S. Geological Survey’s exhaustive Water Use in the United States surveys. In the Lower Basin, the Castle et al. paper showed declines in groundwater levels at a time when analysis based on groundwater well data showed aquifers rising across a substantial part of the area in question.

Scanlon concluded that in the Colorado River’s Upper Basin, the loss of water identified by GRACE came in part from a reduction in reservoir storage, with the rest of the loss of water attributable to the natural loss of soil moisture that occurs across large areas during drought – not groundwater pumping.

In the lower basin, the new paper concludes that aquifer levels are stable or rising beneath the most populated parts of the state – the Phoenix-Tucson corridor – and that the groundwater losses seen by the satellite data are primarily in outlying areas where groundwater is less well regulated (something that is a hot topic of discussion in Arizona right now).

Some back story on why I was so interested in the new paper…. I was enthusiastic about the Castle paper when it came out, but when I went looking to “storyize” it for my book, it left me scratching my head. The original work was a groundbreaking attempt to apply the GRACE tools to the Colorado River Basin, but the data was too coarse to say where in the Basin the overpumping was happening. The paper argued that policy action was needed, but where? Beyond anecdotes, when I dug into the numbers looking for a way to tell a story that demonstrated the scale of overpumping the Castle paper argued was happening – enough farm acreage or municipal water use to match up with the groundwater use the Castle paper claimed – I was stumped. The numbers didn’t seem to pencil out, creating one of those “danger, journalist doing math!” moments I’m so prone to. I looked at USGS groundwater pumping data, and remote sensing data of ag acreage, and none of it added up. I’ve spent a lot of time in the last year trying to understand what can be said about who’s using water how and where in the Colorado River Basin, and I just couldn’t find where all this pumping could be. There literally weren’t enough farms and cities, especially in the upper basin, to account for the pumping the Castle paper said was happening. (“Danger, journalist doing math!”) I never ran across Scanlon or any of the authors of this new paper, but other scientists I talked to who work on groundwater and Colorado River Basin issues raised some of the same questions addressed in this new paper, describing methodological uncertainties could have led to an overstatement of the amount of groundwater being pumped. A paper by Bill Alley and Leonard Konikow discusses these methodological issues. One of my groundwater tutors, Michael Campana, (whose old University of New Mexico office I now occupy!) also raised questions early on. For my book, I just moved on, but I worried that the missing water was out there, and that I was just missing it. If that makes any sense. The Scanlon paper helped me sort out the discrepancy.

Sorry for the ramble, but this has been a nagging loose end. And a huge thanks to both groups of researchers. This is hard, cutting edge science, which is very relevant to water management policy.

Is the Colorado River Basin half empty, or half full?

Data source: USBR. 2016 projection based on USBR October 2015 24-Month Study

Data source: USBR. 2016 projection based on USBR October 2015 24-Month Study

Preparing to moderate a panel at next week’s Colorado River Water Users Association annual meeting, I’m struck by the mix of good news and bad news on the river. 2015 water use across some major user groups is at record lows for the modern era, something that I don’t think gets enough attention. But Lake Mead keeps dropping.

Being the optimist, I’ll start with the good news.

As we near the end of 2015, this morning’s Bureau of Reclamation year end water forecast (source pdf) includes some encouraging numbers:

  • at 2.476 million acre feet, the Imperial Irrigation District’s forecast water use for the year is the lowest since at least 1964, which is the start of the bureau’s modern water accounting era
  • Nevada is forecast to take a net (after return flows are accounted for) of just 222,441 acre feet from Lake Mead, the least water used in Las Vegas and surrounding areas since 1995. The region’s population has doubled since then.
  • Arizona’s on-river agricultural communities (La Paz and Yuma counties, representing collectively the state’s biggest and oldest Colorado River ag water rights) are on track to use 936,000 acre feet of water, also the lowest since the modern accounting system was put in place.
  • The Central Arizona Project, which moves water up out of the river corridor to Phoenix and Tucson and surrounding environs, is on track to pull 1.513 million acre feet from the river, which is the second lowest (after 2005) since the system was built out and began full operations in the late 1990s.

This clearly shows some significant “use less water” adaptive capacity in the system. And yet….

The bad news

Total reservoir storage on the Colorado River system as of Monday was just 50 percent (source pdf). Lake Mead ended November with a surface elevation of 1,078.23 feet above sea level, the lowest for that date since it was filling in 1938.

The balancing act

This is the balancing act – a need for a recognition of the seriousness of the problem (Lake Mead keeps dropping!) while simultaneously also recognizing that significant progress has been made in using less water, and learning the lessons offered by that progress.

Let me know if you’re going to CRWUA, track me down, say “hi”.

the “stickiness” of drought conservation messaging

Jon Christensen makes a great point:

Christensen says experts learned lessons about the “stickiness” of behaviour change during California’s drought.

“When there’s a lot of messaging about conserving water, when there are incentives to conserve water, people do conserve water, they use less water,” Christensen says.

“And when the drought is over there’s some rebound, but those conservation measures do tend to stick at the municipal level and at the household level. You learn new patterns and then those patterns can stick.”

 

The decline of Arizona cotton

Arizona cotton acreage this year is the lowest it has been in nearly a century.

Cotton is incredibly important in the evolution of western water policy, in Arizona in particular and therefore in the Colorado River Basin in general. In Arizona, it was one of the “Three C’s” that dominated the state’s economy – cattle, copper, and cotton. The need for water to irrigate a cotton empire was foremost in the minds of state leaders when they asked the U.S. Supreme Court to intervene in Arizona’s dispute with California over Colorado River water. State leaders grasped earlier than most that their aquifers couldn’t sustain the 1950s-era groundwater pumping that was fueling the cotton boom.

In 1953, there was 695,000 acres of irrigated cotton in Arizona. In data released today by the USDA, that was down to 101,000 acres:

Arizona cotton

Arizona cotton

That is the lowest Arizona cotton acreage since 1921, according to the USDA. There are a lot of factors at play here. Water is just one of them. But Arizonans are using less of their scarce water growing cotton than they used to.

The institutional hydrograph: New Mexico’s Rio Grande in December

With fall semester over yesterday, I called “faculty prerogative” and went out with Lissa for a weekday afternoon walk by the Rio Grande. I’m just an adjunct, but I’m trying to model the behaviors of my more distinguished university colleagues, and one of them is the rhythm of the academic calendar. Finals week is still underway, and the real faculty members still have to deal with grading and the bureaucracy of the end of the semester, but I’m just an adjunct, right? So my semester’s over. A walk by the river it was.

Rio Grande water flowing through Albuquerque, on its way to Texas, Dec. 9, 2015, by John Fleck

Rio Grande water flowing through Albuquerque, on its way to Texas, Dec. 9, 2015, by John Fleck

The grad students in our Water Resources Program “Contemporary Issues” class, the introduction to their masters degree curriculum, gave their final project presentations yesterday afternoon, and I couldn’t have been more pleased. One group studied New Mexico’s state and regional water planning process, one worked on direct potable reuse (“Don’t call it ‘toilet to tap’!”), and one reviewed the institutional framework in New Mexico for instream flows, as compared to other western states. All three groups showed me things I didn’t already know, and all three really wrestled with the deep difficulties of the water management problems they were studying.

Water management is hard.

The Rio Grande was booming today (at least relatively speaking – it’s a desert river), and it’s worth pondering why, in the context of what our students have been thinking about over the semester. Our curriculum puts a lot of emphasis on institutions, those formal and informal rule systems that govern the allocation, distribution, and management of our water. There’s a plain language meaning of the word that’s narrow, where “institution” == “government agency”. But one of the critical points we work on in class is understanding institutions more broadly, as the set of rules, both formal and informal, that govern repeated interactions among people. Government agencies are a piece of this, but it’s really the rules (and critically, both formal and informal, the guiding norms) that matter.

The rules that govern flow in the Rio Grande are complex and interlocking but one of the most important is the Rio Grande Compact, a contract among the three U.S. states that share the river (and the federal government – the feds are always part of compacts). The most important rules right now, as the Rio Grande flows through Albuquerque this warm December, involve the calendar. The compact sets out how much water New Mexico can use as the river flows through the state, and how much must be passed on to Texas. The accounting is done on a calendar year basis. So at the end of December, everyone’s gotta try to make the books balance.

Source: USGS

Source: USGS

The implications for river flow through Albuquerque are fascinating. One of the basic tools of water management is the “hydrograph”, a graph of water flow relative to time. I’ve plotted up the winter hydrograph of median daily flow on the Rio Chama below Abiquiu Dam, the main regulatory structure upstream of Albuquerque. Every year in October, as the irrigation season winds down, releases from the dam steadily drop. And then in December, they tend to rise again for a few weeks. What’s up with that? There’s no phenomenon in the weather than might explain it, is there? December rainstorms?

No. It’s accounting. Frequently at this time of year, water that had been held in storage is moved downstream through Albuquerque and into Elephant Butte Reservoir, which is essentially the Texas compact bank account. It’s an accounting transfer, to make the books balance by the end of December.

One could imagine different sorts of institutional arrangements that might find advantages to moving that water at a different time of year. Perhaps (just speaking hypothetically) one might find advantage to moving it in the spring, for example, when additional water to support spring spawning of an endangered fish of some sort might be of value. But the institutions are what they are, and the calendar is what it is, and the water’s moving now. Check it out, it’s really nice down by our river right now.

You see these “institutional hydrographs” all over. My favorite is the Grand Canyon, where the Colorado River rises and falls in a diurnal cycle that’s linked to the use of Glen Canyon Dam to generate peaking power during times of high electricity demand. Big dams are great for that.

This year the Rio Grande accountants are unusually busy, with a lot more water flowing through Albuquerque than usual and a lot more interesting accounting. The institutional stuff gets complicated in a hurry. Right now there are three different accounting systems being balanced with a lot of water moving as a result. But the thing to watch is that January dropoff. If you’re in Albuquerque and enjoy a bit of water in your river, check it out now. The accountants should have their books balanced by the end of December, and the river will settle back into the quiet of winter.

Inkstain holiday gift guide

It's a drought. We need more rain.

It’s a drought. We need more rain.

Just give ’em Rain. I don’t mean the stuff falling from the sky. I mean Cynthia Barnett’s natural and cultural history of the stuff falling from the sky. Terrific book, just made the list of finalists being considered for the PEN/E.O. Wilson Literary Science Writing Award. Even if they’re not a water nerd, they’ll love it.

If they’re a kid? Give ’em The Tree Rings’ Tale, which I wrote a while back. Nah, who am I kidding, the kids’ll like Rain too. Just give ’em that.