The Institutional Hydrograh: Article VII of the Rio Grande Compact

If you’re following flows on the Rio Grande through New Mexico this spring, no doubt you noticed the big drop this morning in releases from El Vado Reservoir on the Rio Chama. (Of course you noticed, right?)

Welcome to what we in the UNM Water Resources Program have come to call “the institutional hydrograph”. It is when the rule, not the climate, becomes the dominant variable influencing flow in a river. It happens all the time.

Up until this morning, inflows and outflows from El Vado Reservoir were roughly in balance. The La Puente gauge, seen in brown, is the inflow. The green line is releases from the dam. You’ve got a nice diurnal cycle at La Puente, which the dam smooths out, but basically whatever water flowed in was simply being passed through the dam.

Rio Chama flows

The river is operated this way because of Article VII of the Rio Grande Compact:

Neither Colorado nor New Mexico shall increase the amount of water in storage in reservoirs constructed after 1929 whenever there is less than 400,000 acre feet of usable water in project storage….

“Usable water in project storage” is, roughly speaking, the amount of water sitting in Elephant Butte Reservoir. “Reservoirs constructed after 1929” includes El Vado and Caballo Reservoirs. Basically this means that when Elephant Butte is empty, we (Colorado and New Mexico) can’t store water upstream, we have to send it all down to Elephant Butte. The accounting rules here can get a bit arcane, but over the weekend “usable water in project storage” topped 400,000 acre feet, so – boom! – we can start storing water in El Vado, cutting flows on the Rio Chama instantly.

There’s so much water piled up at the next reservoir downstream, Abiquiu, that the cut in Chama flows shouldn’t be seen here in Albuquerque, where the river has been edging out to the levees with some of the highest flows in years. And there’s so much snow still in the upper elevations in the headwaters that this will be going on for a while.

So if you’re in Albuquerque, head out to the river, early and often. It’s an amazing sight.

Rio Grande, overbanking into the bosque, Albuquerque, New Mexico, May 12, 2019

Mo Hobbs on the interdisciplinary nature of water

“My research integrates elements of biology, hydrology, and geomorphology,” said Hobbs, who is currently working on her Masters’ in Water Resources in UNM’s Water Resources Program. “In New Mexico, the water is more spoken for than it is present. The use of water must be allocated amongst multiple users while also trying to maintain a life for aquatic organisms and habitats.”

Monika “Mo” Hobbs on her work on the Rio Chama., capturing, in a better nutshell than I’ve ever seen, what our program is all about.

I love our students.

When you cross a bridge, look down

on a bridge, looking down

When you cross a bridge, Craig Childs said at an American Rivers gathering in Santa Fe Friday evening, stop, and look down.

A couple of llamas stared in what I imagine was puzzlement this morning as I dropped my bike and walked out onto the planks bridging one of the irrigation ditches in Albuquerque’s South Valley. Today is my 60th birthday, and I took a long morning bike ride that (metaphor alert) included a lot of stopping on bridges and looking down.

for example, a llama pasture

This is a common feature of the valley ditches – a control structure that can be used to raise the water level to reach irrigation turnouts to divert water into, for example, a llama pasture. This particular ditch is nameless to me, part of the complex system through which the Rio Grande splays out across Albuquerque’s valley floor to irrigate, for example, llama pastures.

Sitting on a panel next to Craig Friday was humbling and a little intimidating. When I was first starting to write what became Water is For Fighting Over, floundering to find a voice, I visited Mesa, Arizona, and this 2007 High Country News Piece of Craig’s:

Phoenix seems either on the verge of unparalleled success or catastrophic failure. At this point, it might be hard to tell the difference between the two.

On Mesa’s mesa you can see the remnants of old Hohokam canals, and I lingered at a modern water drop from one of the Salt River Project concrete behemoths into some of the remnant citrus groves up against the now-mostly-dry Salt River’s bed.

What was quite literally the first draft I wrote was voiced in response to Craig’s piece, and I set out to try to answer the question he had posed – about Phoenix and all of the West. Which are we on the verge of?

I am not the poet, my gifts if I have them more technocratic. As I carried out Craig’s advice this morning (“When you cross a bridge, stop, and look down….”), I tried to smell the river. (“My earliest memory is the smell of water in the desert,” Childs has written.) I feel prosaic and not at all the poet I imagined I would become when, as a substitute for smell, I stand on the Central Avenue Bridge and look up the Rio Grande’s flow on my iPhone. (5,050 cubic feet per second, the highest flow on my birthday since 1993.)

But as I cross over into my 61st year (metaphor alert) I am comfortable with what I see beneath the bridge, the voice I have finally found.


Fishing the ditches

I had a fascinating conversation this morning with the guy in the hat, who was out with his family fishing where the Middle Rio Grand Conservancy District’s Central Wasteway drops water out of the Albuquerque irrigation system, back into the Rio Grande.

Fishing the Central Wasteway

I’ve been bicycling to this bridge three or four times a week recently, because it’s one of the best places to watch the changes in the rising Rio Grande. With a big snowmelt building, we’re seeing some of the highest flows in years, and I’m missing none of it.

I’ve been talking to our UNM Water Resources students about a cormorant I’ve seen off the bridge, fishing at the confluence between irrigation system and river – a boundary between nature and not nature. Perhaps. Today was the first time I’ve seen humans fishing there. Apparently it’s a good place for fish.

The guy in the hat gave me a marvelous rundown of the best places to fish in the MRGCD ditches. I didn’t have anything to take notes (Note to Fleck: carry the damn notebook when you’re riding!), but I do recall that one of the best fishing spots in the valley is the ditch behind the Walmart at Dennis Chavez and Coors in the South Valley. I remembered this particularity because my friend Scot lives across the alfalfa fields (one of the valley’s last big farmed patches) from Walmart.

Apparently if he was so inclined, Scot could fish out the ditch behind his house, as well as irrigate.

The cormorant fishing off the bridge is interesting. In the decade or so I’ve been birding the riverside woods, I’ve noted an increase in the number of cormorants. I hypothesize that they’ve been drawn by the stocked fishing ponds a mile to the south, and are now spreading out to the river.

“Nature,” writes Robert Macfarlane in the delightful Landmarks, which my sister, Lisa, gave me for my birthday, “is not now, nor has ever been, a pure category. We inhabit a post-pastoral terrain, full of compromise and modification.”

I think one of the fish the guy in the hat told me about was carp.

Adam Smith on the value of water

The word value, it is to be observed, has two different meanings, and sometimes expresses the utility of some particular object, and sometimes the power of purchasing other goods which the possession of that object conveys. The one may be called value in use; the other, value in exchange. The things which have the greatest value in use have frequently little or no value in exchange; and, on the contrary, those which have the greatest value in exchange have frequently little or no value in use. Nothing is more useful than water; but it will purchase scarce anything; scarce anything can be had in exchange for it. A diamond, on the contrary, has scarce any value in use; but a very great quantity of other goods may frequently be had in exchange for it.

Adam Smith, Wealth of Nations

Central Arizona ag’s decline continues, but Pinal County is up

In the wake of Arizona’s difficulties in coming to terms with the future of central Arizona agriculture as it sorted out its approach to reducing Colorado River water use under the Drought Contingency Plan, the latest Census of Agriculture data is fascinating.

Irrigated agriculture in the Central Arizona Project counties

The decline continues, but only just barely. The data within this data, broken out by county, is fascinating:

Central Arizona irrigated acreage, by county

Pinal County agriculture, with receives heavily subsidized irrigation water via the Central Arizona Project, has actually been expanding since the 1980s, according to the Census of Agriculture.

New Mexico’s Rio Grande, rising

My co-author Eric Kuhn was in town over the weekend to finish up the copy edits for our upcoming book Science be Dammed, and happily we were not so busy that we didn’t have a chance to get in a couple of bike rides. (In our collaboration these last few years, “Are you going to bring a bike?” or “Should I bring a helmet?” have played an valuable role.)

Eric Kuhn at the Rio Grande, Albuquerque, New Mexico, April 2019

We got rides out to Albuquerque’s Rio Grande both Saturday and Sunday, and with the river rising in response to our big snowmelt, we started to see some “overbanking” in channels build by environmental engineers to mimic the old flood plain flows this valley used to see.

I am obsessed, and have been getting out lately nearly ever day (one has to ride one’s bike somewhere, right?) to see the river rise. Here, for those in Albuquerque who want to enjoy the obsession along with me, is a map to a couple of my favorite spots right now:


Both are easily accessible via the city open space trail that starts at the parking and picnic area on the north/east side of the river just upstream from the Central Avenue Bridge.

Water, seeping through language

Deep in the copy edits for our new book, Eric and I have stumbled into this minor obstacle:


It’s a fascinating reminder of the way the words of water are everywhere, carrying their separate linguistic cargo. And, thanks to the modern technology of search-and-replace, it is a problem easily solved.