Ribbons of Green: The Hubbell Oxbow

The Hubbell Oxbow, a “lake” in Albuquerque’s South Valley turned flood control channel (with bonus cottonwood grove)

The big farms we have left in Albuquerque’s South Valley are weird.

Riding the old Hubbell “Lake” and Anderson Farms – red is the Sunday bike ride

I spent a good fraction of my weekend staring at maps of them, or riding my bike around them, or both.

My co-author Bob Berrens and I have zeroed on in this area for a key part of the storytelling in our new book, Ribbons of Green. It has it all:

  • the old Camino Real running up the river’s edge
  • an enduring indigenous Pueblo to the south
  • two enduring (?) Spanish-era villages
  • 21st century farm land that is crucial to our narrative precisely because it is not enduring

It’s this last bullet that was the focus of my latest squiggly Sunday outing.


The book will be published (once we write it!) as part of the University of New Mexico Press’s New Century Gardens and Landscapes of the Southwest series.

The notion of “gardens” came to us after the notion of the book, which is an effort to tell Albuquerque’s story in terms of our community’s relationship with its river. By our “relationship” with the river, we do not mean how we feel about the river today, how we interact with it, in its modern form. Rather, we’re trying to tell the story of how we came to build our city in the bed of the river itself. Because the Rio Grande of today, pinned between levees, bears little relationship to the river the Puebloans, the Spanish, and the early Americans confronted when they set about to build a city here.

Here’s a squib from the book’s opening chapter:

Through its history, the English language word “garden” has done yeoman’s work, traveling with us as we made a modern world. At its simplest, it is a noun describing a place out behind the house where we grow flowers, and vegetables, and perhaps a few fruit trees. At its most expansive, it is “a region of great fertility.” Kent was “the Garden of England”, “known for its abundance of fruit and crops”. The province of Touraine was “the Garden of France.” But it is the noun’s interplay with garden’s verb form that does the word’s linguistic heavy lifting – “to bring a landscape into a particular state” – to change our world.[ “garden, n.” OED Online. Oxford University Press, December 2021. Web. 27 February 2022; “garden, v.” OED Online. Oxford University Press, December 2021. Web. 27 February 2022.]

It is this notion of “bringing a landscape into a particular state” that has brought me, again and again, to the neighborhood around the Walmart at the corner of Coors and Rio Bravo in Albuquerque’s South Valley.

Hubbell Lake

Hubbell Lake, 1920’s Plane Table Maps, sheet F6P113, courtesy MRGCD

Bob and I have been working with a bunch of old maps, trying to understand the evolution of that landscape as the community that was Albuquerque-in-becoming developed the institutions that eventually made it possible to put a Walmart in a spot that, as recently as the 1920s, had been labeled “lake” on the maps of the day.

The largest farms left in the Albuquerque reach of New Mexico’s Middle Rio Grande are here – much of the land in public ownership, leased to alfalfa farmers selling their crops to local equestrians, an effort by the community to preserve an agricultural heritage that looked nothing like this.

And not here. The agricultural heritage of this landscape is a recent creation, only made possible when the community added what looks kinda like Dutch technology – dykes to keep the river in its place, and drainage to lower the water table from the land beyond.

This was a flood path, a sweeping bend in a secondary river channel, inundated in high flows, that was used in the time before as pasture and a duck hunting club.

Thus does “lake” become farmland and a Walmart. It’s a very 20th century innovation. Before we did all this stuff, this stretch of the valley was salt grass marsh and “lake”.

This is the project of our book – to explain the processes of collective action that brought this particular landscape into this particular state – “gardening”.

A Lovely Grove of Cottonwoods

On our Sunday bike ride, my friend Scot and I rode into the Hubbell Oxbow from the west. The land is outside Albuquerque’s city limits, but is owned by the city’s Open Space program. It’s not really open to public access, but it’s easy to get in via the Middle Rio Grande Conservancy District’s Gun Club Lateral, the irrigation canal built in the 1930s (? – further research needed, but we think this timing is correct ?) and/or the Albuquerque Metropolitan Arroyo Flood Control Authority’s Hubbell Channel, built in 1978. (I’m more confident about that date, which I got from the AMAFCA GIS database we’re using.)

Scot’s an incredibly important unindicted co-conspirator on the project, assisting in the crucial research task of aimlessly riding our bikes around the valley floor looking at stuff.

Our current work in the South Valley is thorough.

Looking at stuff is key.

The stuff we found Sunday, slipping into the Hubbell Oxbow from the back, was lovely. Wrapping around the back of the farm, protecting the farmland itself with a levee, is a flood control channel and basin that have, in fine AMAFCA tradition, become a greenspace. I was about to type “community greenspace”, but that doesn’t seem quite right if, by “community”, we mean a place where the locals walk their dogs and ride their horses and bikes. Despite the easy access, it doesn’t seem to get much of that sort of use. To quote the city, “The property does not offer formal access.” (emphasis added)

But if by “community” we are comfortable attaching what the economists might call an “existence value” – a thing that we value simply in the knowledge that it exists, rather than a “use value”, which we value via horse and bike and dog walk, then yes: “community greenspace”, I guess.

This spot is a classic type section of the “ribbons of green” of our book’s title.


the rise and fall of “the flood menace”

via Google Ngrams, the rise and fall of the flood menace

Doing reading for the new book on early 1920s Albuquerque, as business leaders pursued what would become the Middle Rio Grande Conservancy District, I see the regular return of a phrase I’d come to see frequently my reading of Colorado River history in the same time period:

the flood menace

Here’s the Albuquerque Journal, reporting on a June 1921 meeting of the Albuquerque Chamber of Commerce, where leaders were gathering support for the District’s creation:

It was further made clear that unless this project is carried through to completion there will be a depreciation of production and land values and ever increasing menace from flood waters.

I love Google Ngrams for this stuff. It allows you to track the rise and fall of a word or phrase in the corpus of English-language writing.

Despite having built a city on the Rio Grande flood plain, we don’t much worry about the “flood menace” these days. But boy, howdy, was it on people’s minds here (and elsewhere) back in the 1920s!


Lukas: “really low #ColoradoRiver flows are off the table. “

Jeff Lukas:


Dead Pool Diaries: Climate change, the doctrine of prior appropriation, and the Colorado River crisis

A desert landscape. Corrales, New Mexico, January 2023. Photo by John Fleck

Writing in 2018 in the Seattle Journal of Environmental Law, Kait Schilling argued that the doctrine of prior appropriation – the notion that those who first put water to use hold priority over those who came later – was no longer compatible with a climate-changed world.

Climate change is diminishing water rights equally regardless of date of appropriation. Such a phenomenon makes the “first in time, first in
right” rule difficult to grapple with because right holders will be unable to access their water to its fullest extent. Because every human has a right to fresh water, the first in time, first in right mentality can no longer be sustained with the current state of climate change and population growth.

The two sides of the argument:

  1. equity requires sharing the pain across all water users – seniors (mostly farms but also Native American communities) and juniors (mostly cities)
  2. to respond to climate change-induced shortages, we need to cut off juniors, or make them compensate seniors for the water they need

This debate is the narrow eye of the needle we’re trying to pass through right now in the rapid-fire negotiations underway to deal with this Colorado River crisis.

The sticking point in the current Colorado River negotiations

In a letter submitted to the U.S. Department of the Interior in December, Arizona’s water leadership – the Department of Water Resources and Central Arizona Water Conservation District – argued for “1”. (Huge thanks to Daniel Rothberg at the Nevada Independent for collecting and posting the letters and also writing some smart stuff about what’s in them – journalism as a public good. The context here is Interior’s request for scoping comments on the agency’s crisis management Supplemental Environmental Impact Statement – SEIS):

All water users share risk from these conditions and the SEIS should ensure that the burdens associated with managing that risk are shared across all sectors and by all water users.

In their letter to Interior, the staff of the Colorado River Board of California argued for “2”:

Finally, some across the Basin have advocated for Lower Basin water users to be individually assessed for reservoir evaporation, seepage, and other system losses. The Board recommends that these losses continue to be treated as a diminution of available annual supply, which can then be met through application of the Law of the River as supplemented by voluntary agreements.

I plead guilty to a misleading oversimplification here, because in their arguments both Arizona and California are making a broader argument about equitable sharing of both the impacts of climate change but also the underlying problem of the river’s overallocation. In defense of my oversimplification, I’ll simply assert that it is the “hot” part of our “hot drought” (see Udall and Overpeck 2017) that makes the difference between the successful gradual process of negotiation we’ve using for more than two decades (see my book Water is For Fighting Over) and the crisis management of 2023.

Could a decent snowpack widen the eye of the needle we must thread?

An improving forecast. Source: Colorado Basin River Forecast Center

Curled up with my morning coffee this morning  (with a huge thanks to the supporters of this blog who bought it for me), I was happy to note that the snowpack is decent right now, and therefore the Colorado River runoff forecast, is up 650,000 acre feet from Jan. 1. That’s an extra ~10 feet of elevation in Lake Powell, which is ~10 feet farther from the white hot fire of crisis management at Glen Canyon Dam.

One argument here is that even a decent year, by lifting the pressure on Glen Canyon Dam -> more water to Lake Mead -> less pressure for really deep cuts now -> less risk of litigation. (I have my own views on this argument – I disagree with it, which I’ll explain below – but I’m trying to do the “view from nowhere journalist” thing here, and I want to give the people I disagree with their best shot, because the argument is not unreasonable.)

The litigation risk

In its EIS comments (see Daniel’s excellent work, did I mention its useful excellence? for the link), the Southern Nevada Water Authority laid out a plan calling for extremely deep cuts regardless of what the near term snowpack and runoff looks like – ~2.6 million acre feet of Lower Basin cuts from the states’ baseline allocations, essentially now. I’m torn between two similarly useful metaphors for what Southern Nevada says is needed – “ripping the bandaid off” and “a tourniquet, not a bandaid”.

In laying out its argument, Southern Nevada does version “1” above, much like the language of Arizona’s letter to Interior, with a call for distributing a portion of the cuts (those allocated to evaporation and system losses) sorta evenly across all water users.

I made much the same argument in my December letter to Interior, so I’m sympathetic to distributing the evaporation and system losses across all users before we think about allocation of the next level of cuts needed.

But here’s the thing that’s wrong with my argument.

To do that, you have to step outside the doctrine of prior appropriation. And the seniors – everyone mentions Imperial Irrigation District at this point, but they’re not the only senior with smart lawyers being asked to take cuts in this scheme, most notably Native American communities, who have deep legal and moral standing – will sue.

Flip the script, though, and try to take tourniquet-level cuts without spreading them broadly and you probably have to dry up the Central Arizona Project canal. Cue the “they’ve got smart lawyers and will sue” song. (To further complicate things, that would jeopardize the rights of Native American communities in Central Arizona that get their water through the CAP!)

This is the argument my smart friends who disagree with me make: A decent runoff this year would allow us to make more modest cuts (still substantial, but not nearly as deep) while avoiding tangling up the whole mess in the courts. I disagree, as I’ll explain below, but it’s not an unreasonable argument.

On bandaids and tourniquets

abandoned boat at Lake Mead

Obligatory “dancing with dead pool” visual reminder

In my comments to Interior, written in a Covid fever in December, I made an argument strikingly similar to Southern Nevada’s (“There was no collusion,” Fleck pleaded. “It’s just arithmetic!”) – that we need deep cuts now and forever. This is the tourniquet argument, and why I disagree with the “take advantage of a decent snowpack to make more modest cuts and avoid litigation” argument. The “now” part is because we’re staring down dead pool, and the “forever” part is that the river was always overallocated, and with climate change it’s now really honest truly overallocated for sure.

Even if we have a decent snowpack, I believe it is imperative that we use that water to refill reservoirs rather than irrigate alfalfa and lawns.

I’m genuinely concerned about throwing this whole thing into the courts. As we learned with Arizona V California six decades ago, litigation is a terrible way to manage a river. Much of our dilemma today is a result of the Supreme Court ignoring arithmetic and allowing us to overuse the river’s water.

My friends who argue for taking advantage of a bit of extra water, if we’ve got it, to try to stay out of court are not making an unreasonable argument.

But we can’t entirely blame the Supreme Court for our troubles. Part of today’s dilemma is the result of our failure to do the hard work of grappling with the court’s mistakes and sufficiently reduce our use of water. We’ve been avoiding litigation for too long by emptying the reservoirs and letting people use the water to irrigate alfalfa and lawns.



Dead Pool Diaries: Jack Schmidt on the hydrologic dance of operating Glen Canyon Dam at extremely low levels

An exchange on Twitter about the definition of “dead pool” sent me back to Jack Schmidt et al’s extremely useful (and now extremely relevant) 2016 analysis of what would be required to empty Lake Powell and move all the water down to Lake Mead.

It’s the thing that disabused me of my simplistic notion that you could operate an empty Glen Canyon Dam as if there wasn’t any dam there at all, just passing the “natural” hydrograph on downstream.

Here’s Schmidt et al:

The relatively small capacity of the river outlets would make it impossible for the flow regime of the Colorado River in the Grand Canyon ecosystem to resemble the pre-dam, natural regime. Instead, stream flow in the Grand Canyon ecosystem would be 15,000 ft3/s or less and would be steady throughout the day. During the spring snowmelt season, however, inflows would greatly exceed the capacity to release water downstream, and the elevation of Lake Powell would increase greatly.

Eventually, the reservoir would get high enough that you could use the old power plant outlets, meaning you could suddenly release a lot more water! Flows at that point jump dramatically. Here’s their graph, with flows on the top in brownish red, and reservoir elevation on the bottom:

Schmidt et al 2016 – operations of Glen Canyon Dam at low reservoir elevations.


The whole paper is worth reading for many reasons, not the least of which is the group’s analysis of evaporation savings of sending all the Powell water down to Mead for storage. (Spoiler alert: Evaporation goes down in one place and up in the other. No free lunch.)

Inkstain tip jar.

The Ghost of the Herrera Ditch

1936 map of Albuquerque's Central Avenue Bridge

Atrisco, circa (I think?) 1936

It’s taking me a while to figure exactly what “the new book” is about.

In an early manifestation (I recall such things based on the names of computer file folders of my scribblings) it was called “the ghost of water”.

The idea was to find threads of the past in the stuff we built to manage our relationships with water, traces remaining of human-built water courses long gone, and of the things we did with the non-human built water courses.

Two stories, or maybe three.

River Westbourne

Westbourne River, in a pipe

A decade ago, when Lissa and I had gone to London for a couple of weeks on a lark, I visited the Sloane Square underground station to see the River Westbourne, carried over the tracks in a big steel pipe.

I’d stumbled in a London bookshop on a slim volume on the city’s lost rivers. Book in hand, Lissa and I wandered from our hotel down to the Thames to the Walbrook Wharf. It was the river that flowed through the old Roman London (the walled city, hence “wall brook”). Its outfall today is at Walbrook Wharf, where container ships fill daily with London’s garbage for the trip to Essex. Seems fitting.

Guerilla historian and urban explorer Steve Duncan wrote this bit:

[C]ities are organic growths that re-use and build on their past. Therefore almost nothing in an older city is going to be perfect, because the systems and infrastructure in use are so often leftover from an earlier period of growth. It’s imperfect, but nonetheless I love seeing the sort of cut-away view of both the history and the physical structure of a city that you get from seeing old underground systems in a modern city.

For “underground” here, substitute “water”. I realized on that London trip a decade ago that the ghosts of water were always there, and that they were a story worth trying to tell.

I also realized a guerilla historian would be a cool thing to be.


I grew up in a California community called Upland.

Photograph of the interior of a citrus packing house in Ontario, ca.1905. Several men man the sorting machine in the foreground which has chutes which spill into bins full of oranges. Several other men are visible standing in the background. A huge stack of orange crates towers over the operation behind. Legible signs include: "Upland Citrus Ass'n, North Ontario, Cal."

Packing citrus, Ontario California, circa 1905. Photo courtesy University of Southern California Libraries

It was, in the 1960s of my youth, on the fringe of the suburbs extending east from Los Angeles, part of the great citrus empire that grew in Southern California after the glorious invention of refrigerated rail shipment brought the exotic delicacy of navel oranges from California to the eastern market.

Upland was part of an irrigation colony developed by the Chaffey Brothers, who brought a convergence of hydraulic engineering and institutions. The engineering got water from the foothills onto the fertile alluvial fans of my childhood, but you needed institutions – the tools of collective action – to make the whole thing work.

The ghosts were there in my backyard, a little concrete irrigation turnout that once watered the citrus trees that had been carefully preserved as our suburban home was built atop the old farmland. It was long after, as I began learning and teaching about water management institutions, that I realized the ghosts of the institutions mattered ever bit as much as the physicality of the thing. For across the street from my childhood home was a tiny reservoir, and it still delivered water – not to groves now, but to homes – courtesy of the San Antonio Water Company, the ghost of the Chaffey brothers’ institutional innovations.

The Ghosts of Institutions

1934 USGS Topographical map of Old Albuquerque, the Rio Grande, and Atrisco

1934 USGS Topographical Map of Old Albuquerque, Atrisco, and the Rio Grand

The shift here – from the physical ghosts of water past to the more ephemeral ghosts of institutions – is the critical piece for understanding where the new book is headed.

Still feeling weak from my CRWUA Covid but desperate to get out and get some exercise, I threw the bike in the car this morning and drove down to the river. Or, more particularly, to Atrisco, next to the river.

It’s at the spot where Albuquerque’s Central Avenue Bridge – Route 66 – crosses the Rio Grande. But, more importantly for out story, it’s where three old ditches that once irrigated what we now call Albuquerque’s “South Valley” had their headings.

Was a time, in the 1700s, when this was the region’s largest population center – the Spanish villages of Atrisco, Pajarito, and Los Padillos. These communities had the best access to sheep and cattle grazing lands to the west. Villages with subsistence farming on the valley floor. Three ditches – Arenal, Atrisco, and Rancho de Atrisco – all had their headworks along a quarter mile stretch of the river bank here. The ditches, providing irrigation water for those subsistence farms, were at once physical and institutional plumbing, the collective action required to dig and maintain the system going on for centuries.

In the 1930s, the individual, community-based systems were taken over by a new collective, the Middle Rio Grande Conservancy District, based on the realization that managing the relationship between the Rio Grande and a growing city required collective action at a larger scale – the individual ditch institutions were incapable of acting at the scale for providing flood control and drainage to the community, which were increasingly the most pressing tasks.

But here’s the interesting ghostly part.

Again and again looking the old maps, I find clusters of ditches with headings near the same spot on the river, each branching off to irrigate a separate down-valley village’s farms. The sophisticated engineers of the 1700s could see, as the river rose to spread across the valley floor during high spring runoff, where the high ground was. The Rio Grande provided a level. Above it was the place to build a village, or el camino, or the headworks of a ditch, which would then follow the contour of the land.

The chapter I’m working on is in terrible shape right now, which is always the case before they get good. But I notice myself writing, over and over again, about this “high ground” thing, ghosts on the landscape of a river we can no longer see and communities adapting their way of life around it.

The title of the post comes from the Herrera Ditch, which my maps show as an abandoned ditch running through what is now an Atrisco neighborhood, just north of El Super, as its name implies, a market – with a great taco bar. (And if you’ve read this far, Bob S, in season they do chile roasting in the parking lot.)

I couldn’t find a trace of the abandoned reach of the Herrera.

This is actionable information. Ghosts remaining are important, as are those obliterated by the erosion of time.

Ribbons Green

The book is Ribbons of Green, which Bob Berrens and I are writing for the University of New Mexico Press. It’ll be a while yet.

Dead Pool Diaries: Colorado River 2022 Year in Review

abandoned boat at Lake Mead

A looming, invisible threat

A review of Calendar year 2022 on the Colorado River

Colorado River reservoir storage dropped 3.1 million acre feet this year, but there is a proposal now being circulated among the Basin States to cut use by that much to bring the system into balance.

Total Storage

Total year end storage in Lake Mead, Lake Powell, and a handful of key Upper Basin reservoirs (Flaming Gorge, Blue Mesa, and Navajo)

  • end of 2022: 16.5 million acre feet
  • end of 2021: 19.6 maf
  • start of the 2000s: 51.8 maf

Source: USBR Hydrodata

a looming, visible threat

Lower Basin Use

Total Use by the Lower Basin States: 6.669 maf, 89 percent of their base allocation of 7.5 million acre feet under the Supreme Court’s Arizona v. California decision. The state by state breakdown:

  • Nevada: 223,512 acre feet, 74.5 percent of their base allocation
  • Arizona: 2,015,097 acre feet, 72 percent of their base allocation
  • California: 4,430,670 acre feet, 100.7 percent of their base allocation

This is Arizona’s lowest withdrawal from the main stem of the Colorado River since 1992.

Mexico received 1.45 million acre feet, 97 percent of their base allocation under the US-Mexico treaty.

Source: Dec. 31, 2022 USBR Lower Basin end of year tally

Total Upper Basin Use

We don’t know yet. It takes a while for the Upper Basin Consumptive Uses and Losses reports to emerge.

I’ll leave a “maybe 4 million acre feet?” placeholder here for now.

Lake Mead Shipwrecks

Total Lake Mead Shipwrecks – sunken speedboats emerging as the reservoir wastes away – that I saw on my pre-Colorado River Users Association bike ride earlier this month: 3.

Cuts needed next year to stabilize the system

Per Reclamation Commissioner Camille Touton, testifying before Congress last year, we need 2 to 4 million acre feet of cuts to stabilize the system.

There was a proposal discussed at the Colorado River Water Users Association meeting in Las Vegas earlier this month (in closed basin states meetings, not in the open sessions) that calls for 2.6 million acre feet in Lower Basin cuts from the 7.5 million acre foot AZ v. CA baseline and 500,000 acre feet in Upper Basin contributions.

That would be a 1.8 million acre foot cut from 2022 levels in the Lower Basin, and another 500,000 acre feet in the Upper Basin.

The proposal came from the Southern Nevada Water Authority, and seems to have been embraced by the other states not as the solution, but as the starting point for a discussion over the next month, with the hope of a Basin States “consensus proposal” by the end of January. This is a good sign. Daniel Rothberg of the Nevada Independent kindly posted the full proposal, as submitted by SNWA Dec. 20 to Interior in response to the agency’s request for comments on its Supplemental Environmental Impact Statement, and Colton Lochhead covered it for the Review-Journal.

I’m hoping to write more about this last bit as soon as my Covid fog clears (caught it at CRWUA and I’m mostly laying around feeling sorry for myself, doing crosswords, not riding my bike, and thinking and writing poorly, hence the brevity – perhaps that’s not a bad thing – I successfully did the Friday New York Times crossword, which I’m usually not smart or patient enough for).

2022: My Year of Riding Everywhere

2022, the year of Squadrats

No bad days on the bike.

At the risk of a tortured metaphor, rides are the warp threads of the loom of my life, bound firm in the frame of the loom as I weave the day’s events around them – the places I go, the things that I do, and the rides that get me there and back.

I remember lunch with my friend Liz – and the bike ride I took to get there, winding through the industrial freeway zone, cranes and graffiti and homeless encampments, on the way to the restaurant.

I remember pre-dawn breakfasts at the Frontier with my friend John, clipping on the lights and bundling against the cold, locking up next to a homeless guy’s epic touring rig, always parked at the same spot, and he’s always sitting at the same spot, sipping coffee to warm up, able to look out the window to keep an eye on the bike.

I remember the conference in Salt Lake City and not one but two epic rides on the way there, in the San Juan Basin and along the Colorado River. The conference in Boulder and the loop with Eric around Dillon reservoir, the ride to the conference from the hotel in the morning and the long walk back to the hotel with my friend Bill, walking the bike through a delightful throng of Deadheads converging for the evening’s merriment, because Boulder, amiright?

I especially treasure Sunday rides with my friend Scot which, absent my crazy Colorado River conference schedule or Covid, anchor each week, foundational.

The joy of the ride to work, and the ride home (I exploited a cool new alley cut-through this year, just a few blocks from my house, how had I missed it all these years?).

Some days I lock the bike at the law school rack, but more often it’s propped up against the bookcase in my office. A happy object always.

Riding everywhere

Tiling Albuquerque – a map of the places I rode in 2022 in Albuquerque


Some years ago I dug through all my old devices and hard drives and cloud services and assembled a relatively complete record of all my bike rides since 2008, what I call “the GPS era” – 5,176 rides, 39,365.1 miles.

All that data sits in Strava, and Strava makes it relatively easy for developers to build creative new products, which has lead to all sorts of mappy game innovations.

In 2020, I was already riding a lot when pandemic isolation turned the bike rides into a desperate, manic adventure. I’d discovered Veloviewer and “tiling” – using our bikes’ GPS records to keep track of where we’d ridden and, more importantly, where we hadn’t.

A map of Albuquerque showing, in blue, streets John Fleck has ridden

In blue, the Albuquerque streets I’ve ridden.

In 2021, I added Wandrer – keeping track of which streets I had and, more importantly, hadn’t ridden.

This year I added Squadrats, which is the most fun of all. Veloviewer’s squares are a bit less than a mile on a side. Ride (or walk or whatever) anywhere in a tile and you’ve got it. The big tiles are pretty easy to get. In Albuquerque, I quickly filled in the entire city.

So after a couple of years of working on it, the only new Albuquerque tiles left required some epic explorations to the west, some clever work to thread through to the south without trespassing on Pueblo lands, and increasingly lengthy adventures to the north.

I’m getting old for “lengthy adventures”, frankly.

And then I found Squadrats. It takes the Veloviewer-sized tiles and doubles (octuples?) down, dividing each tile into 64 mini-tiles. The result was a year of joyous riding going back to all the little tiny bits of Albuquerque I’d missed. Using the standard Open Street Map grid, it divides up squares that vary by latitude, but here in Albuquerque they’re about 800 feet on a side. Filling in a map at that density requires geographic intentionality, focus.

Farm field, irrigation ditch, and junk yard

The rural-junkyard interfaced.

Thus a “wrong turn” down the cart path at Los Altos Golf Course (“I’m sorry, it looked like a bike path.”). A flood control tunnel in the far northeast. The junk yard hard against an irrigation ditch and alfalfa field in the South Valley. Places I’d never have gone in the pre-Squadrats era.

Even before tiling, our practice of riding in weird places has always encouraged strange encounters.

My favorite was the time the caretaker at the Albuquerque Dragway politely informed us one Sunday morning that we weren’t supposed to be there. “Chased out” is too strong a word for the encounter as he rode up on his ATV. It was a polite exchange, though it was hard to make the “wrong turn” argument given that we’d lifted our bikes over a locked gate to get in. He then escorted us out and, in answer to our question, pointed us to a good spot to hop another locked gate to trespass on his neighbor’s property.

Good guy.

This year’s best Squadrats tiling adventure involved being politely told we had to leave Albuquerque’s Balloon Fiesta Park (“So sorry,” we said, pointing helplessly at our mobile phones, “Google made it look like this was a road.” Works every time.), then circling around the far side and sneaking back in.

Tiling can feel a bit rascally. That’s a part of the fun.

Fleck’s Squadrats map. New mini-tiles for 2022 in green.







At CRWUA, inklings of a Colorado River compromise

two lawn chairs on the Lake Mead shoreline

Ringside seats to the decline of Lake Mead

I came away from a week in Las Vegas more hopeful about a deal to prevent a Colorado River crash than I have felt since the ominous day last March when Lake Powell dropped below elevation 3,525.

The annual meeting of the Colorado Water Users Association is a bit like the shadow puppets of Java – projections onto a public stage of things hinted at but largely unseen behind.

On display in public this year, in the formal CRWUA panels, was a frank discussion of the river’s problems that I found unprecedented.

Behind, in the realm of the puppeteers, was even more frank talk about the shape of a deal that would be needed to halt the reservoirs’ declines. It’s still a longshot, with a narrow path to success and a very tight deadline – whatever “consensus plan” the seven Colorado River Basin states come up with has to be delivered to the Department of Interior by the end of January.

But going into CRWUA, I could see no path. Now one is dimly visible.

Managing based on inflow, rather than reservoir levels

A Kuhnian paradigm shift?

At the heart of the art of the possible here is shift in the discussion of a management framework, from the well-worn path of management by reservoir levels (if Powell “x” and Mead “y”, do “z”) to a system based on inflows. If less water flows in, you have to take less water out.

Phrased that way, it sounds so obvious, but it’s a major shift from the way the system was built and has been managed for a century. The reservoirs were built to store surplus when it’s wet to be used when it’s dry. I try not to use the phrase “paradigm shift” loosely, and it’s not entirely clear that it applies here. But the change that we’re seeing bears a lot of the hallmarks of the historian and philosopher of science Thomas Kuhn’s original formulation of the concept – the accumulation of enough anomalies that you can no longer stick to the old way of thinking.

I point here, by way of metaphor, to the accumulating shipwrecks emerging from the shores of Lake Mead.

What the hydrologists call the “mass balance problem” makes this inevitable. In the long run, you can’t take more water out of a reservoir than flows in. But the realization earlier this year that Reclamation’s engineers are uncomfortable using Glen Canyon Dam’s lower elevation outlet works has place the mass balance barrier squarely within the range of the next few years’ planning. If you believe them (and, importantly, the Department of Interior seems to), then there’s no way around shifting pretty quickly to a management regime in which the water you release from Lake Powell has to match up each year with the amount that flows in.

So what changes in river management when you shift to an inflow-outflow regime?

As soon as you adopt a policy that says that releases from Lake Powell are essentially limited to what flows into the reservoir – which is the practical equivalent of “protecting elevation 3,490” or whatever line the river management community chooses above that to offer a safety buffer – 3,525 used to be the number people talked about, but we blew right through that last March – you trip two significant management triggers:

  • you face the very real prospect of Colorado River flows past Lee Ferry dropping below the 10-year standard set by the compact, triggering either a compromise or a very ugly legal fight
  • you face the very real prospect of deep cuts for water users in the Lower Basin, because you pretty quickly turn Lake Mead into an inflow-outflow system too – and/or very ugly legal fights

I could have written all of that before CRWUA began. In fact, I did.

But going into CRWUA I believed the only way to tackle those problems was with a federal intervention. Now there seems a hope of a collaborative solution – of which I’m a big fan.

Relaxing the Lee Ferry Constraint

There were encouraging signs this week that compromise might be possible on the first point, that the Lower Basin might agree to look the other way at a Lee Ferry shortfall, if the Upper Basin states are willing to get past their “it’s a Lower Basin overuse problem” mantra of recent years and kick in some reductions of their own. My read on the situation is that it won’t take a lot of water – folks in the Lower Basin get the fact that it’s primarily their problem. But I’m not in the negotiating room. This will almost certainly be harder than my usual naively optimistic expectation, right?

Cutting Lower Basin Use

Regardless of how the Lee Ferry thing plays out, the hydrologic reality is that there will have to be deep Lower Basin cuts – far deeper than anything contemplated to date. The fact that extreme scenarios are being discussed among the states, rather than having state officials step aside and make the federal government impose them (or, in reality, as newly named Upper Colorado River Commission member Anne Castle reminded us, having climate change impose them) was encouraging to see in the shadows of the CRWUA puppets visible to us outsiders.

That’s incredibly important to the Lee Ferry point, because if the Lower Basin can get together and take on the herculean task of coming up with a formula to agree to the necessary cuts rather than having them be imposed, the Upper Basin is more likely to be willing to contribute without their longstanding worry that anything they kick in will just be sucked up and used in the Lower Basin.

In other words, legitimate action by the Lower Basin states makes Upper Basin action more possible.

My twinkly collaboration fanboy smile should not mislead you into thinking this will be painless – there will be a lot less water for cities and agriculture, and it would be a legal and moral failing if Tribal sovereigns are not brought into this discussion. All of those things make this really hard.

What Happens Next

All of this – an implicit relaxation of the Lee Ferry constraint, voluntary deep cuts in the Lower Basin, and an Upper Basin commitment to contribute some water – seemed to me beyond reach before we gathered at CRWUA. But behind the scenes there was serious, good faith attention to all of them, without the people making the proposals getting laughed out of the room. As Southern Nevada’s John Entsminger told the Nevada Independent’s Daniel Rothberg, the basin states are “still fairly far away from coming to consensus, but we’re closer than we were on Monday.”

Responses to Interior’s request for comments on its crisis-management-in-real-time planning effort are due Tuesday. It will be interesting to see if any of the Basin States offer up a formal first pass at a plan. And Reclamation has asked the states to provide a consensus scheme by the end of January.

Heading into CRWUA, I believed no such consensus was possible. I’ve updated my priors.

If elevation 3,490 is Lake Powell’s new “dead pool”

abandoned boat at Lake Mead

Lake Mead shipwreck

LAKE MEAD – The Park Service has cut a raggedy new dirt road (“4×4 recommended”) north of Hemenway Harbor along Lake Mead’s receding shoreline so you can still get in to go fishing and do the beach thing.

Mead was at elevation 1,043 and change as I rode it on my bike yesterday afternoon, with lunch and time on my hands to ponder the stakes. You could see the uppermost Las Vegas water pipe, exposed to the winter air, and the stranded intake from the World War II-era Basic Magnesium factory.

I passed three Lake Mead shipwrecks, the media icons of the great collapse, ruin porn of the Colorado River. I was happy, I guess, to finally bag the pictures for myself. I guess?

It was my annual pre-Colorado River Water Users Association Lake Mead visit – a bike ride along the reservoir, a trip to Hoover Dam, some quiet time in Boulder City before heading into the madhouse of Las Vegas and CRWUA and a Colorado River in crisis.

Managing in crisis mode

The challenge right now is a very practical one. We’ve no longer time the sort of vague generalizations I got when I turned to ChatGPT for help – “Implementing stricter water usage regulations and reducing water waste can help bring the supply and demand of the Colorado River into balance.” Great. Thanks. How we gonna do that?

The Colorado River brain trust has to write new rules, and it has to write them now, in a very specific way, with little time or room for error.

I have long had a dodge when reporters or my students or whoever asked me what I think we should do: It doesn’t matter what I think we should do, I would tell them. What matters, I would say, is what emerges from the seven states and the federal government, and increasingly the Tribes and others who who now, rightly, find themselves at the negotiating table(s).

Unfortunately, what has emerged from that process is shipwrecks emerging from Lake Mead.

So I’ve dropped the shield and begun thinking about how I would rewrite the rules, if anyone asked me. Come to think of it, the Federal Government has asked me, along with all the rest of you, via this Federal Register notice. You’ve got a week left before your assignment is due.

Basically, we need to do two things.

First, we need to rewrite the rules governing releases from Glen Canyon Dam to protect Lake Powell from reaching critically low levels that, by forcing the use of the dam’s lower outlet works, might threaten the structural integrity of the dam. We do this by setting a maximum release from Powell based on the current year inflow.

Second, we need rules to cut far more deeply into Lower Basin water use, like right now – far deeper than the rules we’ve got now. They’re just not sufficient. We have to include evaporation and system losses as part of each Lower Basin state’s allocation.

Saving Glen Canyon Dam

Section 6, Interim Guidelines

Section 6C and 6D of the 2007 Interim Guidelines is the critical first step.

This is where the current rules lay out how much water is to be released each year from Glen Canyon Dam. Note the quaintly anachronistic “Lake Powell Active Storage” column on the right, with “dead pool” – zero active storage – at elevation 3,370.

If Reclamation decides it doesn’t trust the dam’s outlet works, which sit down there, then suddenly “active storage” doesn’t start until elevation 3,490, the level of the power plant intakes.

For now at least, 3,490 is the new dead pool.

That would mean that at elevation 3,525, rather than having 5.93 million acre feet of “active storage” – the amount of water above “dead pool” – we’ve really got less than 2 million acre feet of really actually usable, releasable water in Powell. The whole notion of “balancing” active storage in Mead and Powell, so central to the ’07 Guidelines, now has to look completely different.

When you get close to dead pool, you’ve got a “run of the river” system, which means that the only water that leaves a reservoir is the amount that comes in. Given that we’re apparently redefining that for Powell on the fly, the new versions of 6C and 6D somehow have to restrict releases from Powell to not much more than comes in. Basically starting now, and for the foreseeable future, until we can begin to refill Powell or drill some new tubes at the bottom that we trust.

A simple approach to the new rule here might be rewrite the release rules when you’re in the “Mid-Elevation Release Tier” (below 3,575) and the “Lower Elevation Release Tier” (below 3,525) to cap releases to inflow minus evaporation. That would set a sort ratchet that would prevent a further decline in Lake Powell below its current dangerously low levels.

You could start the year by capping Powell releases at the 24-month study’s “minimum probable” unregulated Powell inflow level, with the option of raising the release an April review based on the “most probable” unregulated inflow. Minus evaporation. You’d have to subtract evaporation from that.

Other than that, the 6C and 6D rules could stay the same.

Saving Lake Mead

As the modeling presented by Reclamation in its webinars two weeks ago shows, if you operate Powell the way I describe under low flow scenarios, you can crash Mead in a hurry. We need rules that are ready for that.

the Lower Basin “structural deficit”, reified

Taking evaporation and system losses off the top before we begin handing out water is a start. The “structural deficit” is real, it’s a result of not taking evaporation and system losses into account, and it’s written in shipwrecks emerging from the depths of Lake Mead.

Right now evaporation and system losses are in the ballpark of 1 million acre feet per year, but to be on the safe side, let’s set them at the 1.2 million acre foot per year level in the classic Reclamation “structural deficit” Powerpoint slide.

So the cuts in section 2D of the Interim Guidelines would have to be rewritten, with Arizona, Nevada, and California taking a proportional share of system losses right off the top.

You can do this some really complicated ways, based on the distance downstream of each user’s intake – so Imperial and Yuma would take a bigger system losses hit, and Las Vegas (pulling straight out of Lake Mead) would only suffer evaporative loss.

That seems like a recipe for scientized litigation, so my proposal is simple: Everyone shares this equally (sorry, Nevada friends).

That would leave us with a base allocation that looks something like this:

old allocation new allocation
CA 4.4 3.696
AZ 2.8 2.352
NV 0.3 0.252


The cuts in the big ’07 Guidelines/DCP allocation tables would then be deducted from these numbers. So under this scenario, if we drop into the Mead elevation 1,040-1,045 tier, the total allocations would be:

1,040 – 1,045
CA 3.496
AZ 1.712
NV 0.225
US Total 5.433


Notably, this gets us to the 2 million acre of cuts Reclamation Commissioner Camille Touton said we need in her testimony to Congress last summer.

Upper Basin

This obviously doesn’t touch the Upper Basin. The process Interior is using for this round of crisis management – a straight up revision to the ’07 Guidelines – doesn’t seem to offer a clear path to force the Upper Basin to come up with contributions of their own. For now, I’m OK with that. Since the ’07 Guidelines were signed, the Upper Basin has delivered more than 10 million acre feet of water above the required 8.25 million acre foot annual requirement. Despite that, the Lake Mead shipwrecks are emerging from the shallows. The key  here is clearly to get Lower Basin overuse under control.

But I don’t think in the longer term the Upper Basin is off the hook. Reclamation’s modeling clearly shows a risk of the Upper Basin slipping below its 82.5×10 obligation if we have a few more bad years. We need a plan to deal with that. And it’s also a matter of fairness, in my view. We all have to contribute.

My scheme for Upper Basin contributions involves the next wet year – figuring out how to forego some of the Upper Basin storage we’ve got and get that water into Lake Powell instead. Suggestions for how to write that rule are welcomed – bonus if anyone can figure out how to fit that into the rewrite of the ’07 Guidelines currently underway.


I still believe in the power of the collaborative governance framework we’ve developed in the Colorado River Basin. As Assistant Secretary of Interior Tanya Trujillo told me when I was moderating her appearance at last summer’s Getches-Wilkinson Center conference, we’d be in a lot worse shape without it.

For what it’s worth, ChatGPT agrees: “Collaboration and cooperation among states and water users is crucial in finding solutions to the supply-demand imbalance on the Colorado River.”