San Diego’s great water use decoupling

The San Diego County Water Authority’s use peaked in 2002 at 732k acre feet. Last year it was down to 522kaf, a 29 percent drop even as population has risen by 12 percent. This is one of many examples of “decoupling” between growth and water use. As we adapt to conditions of increasing water scarcity in the western United States, this is a good thing. But as Ry Rivard reports in Voice of San Diego, there are downsides:

Over a decade ago, Southern California water officials rushed to build or expand treatment plants so they could keep up with the demand for drinkable water. That cost hundreds of millions of dollars.

Now demand for water has fallen dramatically. The treatment plants sit largely unused during parts of the year and officials are fighting over how to pay for some of them.

In which Russian pirates publish my previous book on the Internet

One of those Russian pirate sites has published a pdf of my previous book, The Tree Rings’ Tale, in the Internet. I feel that, as an author, I have now arrived:

Russian pirates

Russian pirates

I of course will not link to the site, if you want to own a copy the honorable thing is to click on this link. But I must admit to being charmed by the reviews. Mohammad BuSaleh seems to have particularly enjoyed it:

reviews of my book

reviews of my book

Despite drought, farmers on central New Mexico’s Rio Grande looking at a full water supply this year

Albuquerque's Rio Grande drinking water diversion dam

Albuquerque’s Rio Grande drinking water diversion dam

Some remarkable news today out of the regular meeting of the Middle Rio Grande Conservancy District board: despite the nth* year of drought, the district’s farmers are likely to get a full irrigation season again this year, according to a report this afternoon from district hydrologist David Gensler.

The forecast is for 60 percent runoff on this stretch of the river (give or take the weather, 60 percent is the midpoint with uncertainty in either direction depending on whether it’s wet or not from here on out), but with some storage cobbled together in upstream dams and some tight management of the system, the irrigators who grow alfalfa and corn and chiles and the like in the valley should get a full supply, Gensler told the board.

Gensler’s tally of water stored behind upstream dams needed to achieve this goal was a hilarious litany of the opportunities and constraints of the institutional water management – you’ve got your Rio Grande Compact Article VII water, your Emergency Drought Water Agreement Water, your “native Rio Grande” storage, your relinquishment credit storage, your San Juan-Chama Project water storage, and I hope I’m not double-counting here.

There’s also a move afoot here to stash away a bit of extra water and use it to help provide a spawning pulse for the endangered Rio Grande silvery minnow. This is good because, as I’ve mentioned before, our successful adaptation to water scarcity on the Middle Rio Grande has not yet extended to nature.

* where n is maybe 15 out of the last 17?

More cuts, sooner, under Lower Colorado deal taking shape

Looks like significant progress toward an Arizona-California deal to slow Lake Mead’s decline, according to a story from the Arizona Daily Star’s Tony Davis:

Arizona, California and Nevada negotiators are moving toward a major agreement triggering cuts in Colorado River water deliveries to Southern and Central Arizona to avert much more severe cuts in the future.

Details still sketchy, with final negotiations still ongoing, but according to Tony’s story, a couple of very important points stand out on which there seems to be general agreement:

  • Arizona would take cuts in Colorado River water sooner – as early as 2017, rather than 2018 under the current operating rules
  • California, which under the current rules wouldn’t have to take any cuts until Arizona’s Central Arizona Project supplies drop to zero, would agree to take some cuts if Mead drops below a trigger 30 feet below current elevation
  • Arizona will spread cuts more broadly among that states users, rather than the current scheme under which ag takes the hit

This will need Arizona legislative approval, according to Tony, which should be interesting given that state’s belligerent tone toward California over these issues.

The whole story is worth a read.

Is Flint a reverse “environmental Kuznets curve”?

One of the most important findings of environmental economics in recent decades is what is called the “environmental Kuznets curve”, a finding that as a community’s affluence rises, environmental “bads” – think air and water pollution, for example – decline. Could what has happened in Flint, Michigan, be evidence that this phenomenon is bi-directional – that as a community becomes impoverished, environmental conditions worsen?

In 1991 Princeton University economists Gene Grossman and Alan Krueger first documented this intriguing and potentially important relationship between wealth and pollution. At the time the United States, Mexico, and Canada were in the midst of negotiating what would become the North American Free Trade Agreement. NAFTA’s critics had objected that the deal would simply shift pollution from the more heavily regulated and affluent north to Mexico. Preparing for a conference on the deal, the pair looked at levels of sulfur dioxide and smoke pollution in 42 countries around the world. They found that as affluence grew in the 42 countries they studied, pollution grew along with it, but only to a point. Once per capita gross domestic product reached an inflection point ($4,000 to $5,000 in 1985 dollars), things turned around. It was as if, once people had their basic needs covered (food, housing, etc.) their desires turned toward a cleaner environment. The pollution curve, at least for sulfur dioxide and smoke, turned back down.

Could the expected income growth in Mexico, the pair wondered, push Mexico’s economy past the point at which the nation’s pollution curve bends back down? “A reduction in pollution may well be a side-benefit of increased Mexican specialization and trade,” they wrote.

Per capita GDP, Flint, Michigan, adjusted for inflation, courtesy BEA

Per capita GDP, Flint, Michigan, adjusted for inflation, courtesy BEA

The inverted U-shaped effect of environmental damage rising and then falling came to be called the “environmental Kuznets curve” after the work of economist Simon Kuznets, who in the 1950s posited a similar relationship between rising income and inequality. The observation resonated in a world in which rich countries seemed to have turned a corner on their pollution problems with things like the U.S. Clean Air and Clean Water acts and the Endangered Species Act, laws that reflected a culturally noticeable pivot in the decades before Grossman and Krueger published their pioneering work. In the years following the paper, a flurry of studies put empirical flesh on the skeleton, measuring the relationship across a range of environmental “bads”, from urban air pollution and deforestation to climate-changing emissions of carbon dioxide. Researchers argued about the statistical measures and the underlying theory, about whether income and wealth were the right causal variables, but again and again, their curves showed the inverted U’s of an EKC.

The story of Flint is well known – a community gutted by economic change, and left in the process with lead-contaminated drinking water. In terms of both total and per capita GDP, Flint’s economy tanked from 2004-2009, then began to recover in the years since. So is this a thing? As communities get poorer, do things like clean water fall by the wayside? Is Flint an example worth looking at, or does the curve above suggest that the timing is all wrong? How might we look more generally for a reverse EKC?


the water conservation ratchet

While there is much water policy Sturm und Drang in California over the extent to which water conservation mandates should or should not be extended now that weather has provide some drought relief, the reality is that the rules may not matter:

The state of California ordered San Juan to reduce water usage by 33% from 2013 levels in response to a statewide drought emergency. While local water supply conditions have improved in 2016 with El Nino rains and some easing in drought restrictions is expected, some degree of conservation has likely become habitual. Usage levels may remain low.

That’s from Fitch’s bond rating on the San Juan Water District. In the topsy turvy world of municipal water management, conservation is a financial problem. But in the bigger picture, these are good sorts of problems to have.

“drought is not synonymous with shortage”

Drought is not synonymous with shortage. Drought occurs when there is a deficit in precipitation, streamflow, soil moisture or all of the above. Shortage occurs when we lack the policies, incentives and technologies to balance supply and demand in a variable and changing climate.

That’s water wonk Dustin Garrick in a new piece urging a rethinking in our response to “drought” and “shortage”, calling for a shift away from our episodic approach. Bonus Steinbeck.

The costs of getting California’s Central Valley groundwater house in order

Groundwater overdraft, especially at the pace and scale now underway in the southern part of California’s Central Valley, has substantial costs – in terms of lost water availability and ground subsidence. But the discussion of those costs often occurs in a vacuum, without a discussion of the very real costs incurred by fixing the problem. People were doing something with that water that was valuable to them, and they’ll either have to stop doing it, do less of it, or find an alternative water source.

One of the most interesting findings in a new paper by a team of UC Davis researchers is the increased pressure on the Sacramento Delta, one of the alternative water sources for the region. Here the authors explain:

The analysis used a hydro-economic optimization model for California’s water resource system (CALVIN) that suggests operational changes to minimize net system costs for a given set of conditions, such as ending long-term overdraft. Based on model results, ending overdraft could induce some major statewide operational changes, including significantly greater demand for Delta exports, more intensive conjunctive-use operations to increase artificial and in-lieu groundwater recharge, and greater water scarcity for Central Valley agriculture.


The many values of Colorado River Basin irrigated agriculture

The East Mesa Water Co., in its grant application to the roundtable, says the ditch has a service area of 740 acres.

And it says the hay grown on that 740 acres is worth about $500,000 annually, assuming a yield of four tons per acre and a hay price of $170 a ton.

The ditch company, however, also says there is more value in how the hay fields look to tourists than in the hay itself, saying the economic value is “closely related to recreation and tourism.”

“The effect on overall commerce would be significant if one of the most scenic views in the valley, that approaching Mt. Sopris, were to be brown and dry rather than green and lush because this ditch failed,” East Mesa’s grant application states.

East Mesa Ditch owners open to leaving water in Crystal River, By Brent Gardner-Smith

The institutional hydrograph: April on New Mexico’s Rio Grande

Rio Grande near Cerro, NM, courtesy USGS

Rio Grande near Cerro, NM, courtesy USGS

Here’s another example of a New Mexico “hydrograph” – the rise and fall of flow on a river over time – driven by rules, not weather. The drop in river flow happens when the irrigation season begins in the San Luis Valley in southern Colorado. Here’s J.R. Logan in the Taos News:

The Río Grande is at the heart of the valley’s massive agricultural industry, and farmers waste no time in taking their share.

“We got to get after it,” says Jay Yeager, head of the Río Grande Canal Water Users Association, which manages a primary irrigation artery in the San Luis Valley.

The rules governing how much Colorado water users can take and how much they must pass downstream for use in New Mexico are governed by the Rio Grande Compact, an agreement among Colorado, New Mexico, and Texas signed in 1938. It is the important implement of governance here, and the flow in the river bears its mark. Here is Logan’s nice explanation of the implications:

The catch – for New Mexico – is that the delivery is calculated on an annual basis, meaning Colorado can let every drop of the river go to New Mexico during the fall and winter while taking most of the river during the spring and summer and still fulfill its debt to New Mexico.

This is a problem if you are a river rafter or a fish, two examples of modern uses and values that weren’t at play in the 1930s when the deal was negotiated.