On the ecosystem benefits of irrigation systems

MRGCD ditches and drains, green

One of the conceptual riddles Bob Berrens and I are working through in the new book we’re pursuing on New Mexico’s Middle Rio Grande, and the work surrounding it, is the ecosystem goods and services across our valley floor provided by the Middle Rio Grande Conservancy District’s web of irrigation ditches.

Where once we had a river meandering across a broad flood plain, we now have a river tightly confined between levees, replaced by said web of irrigation ditches.

Anecdotally, I see a couple of things in my wanders of the valley floor.

The most obvious is the neighborhood amenity value. People love these ditches! During the pandemic’s peak, ditch walking exploded (says Mr. Anecdotal Evidence, whose ditch bike riding similarly exploded).

My basic conception of what I mean by the “river” long tended toward the main channel itself – the relatively narrow strip that includes the flow of water between the levees. But in recent years I’ve become increasingly convinced that doesn’t fully capture the modern ecosystem.

The bits between the levees – a narrow channel of water dotted with sand bar islands that are increasingly covered by vegetation, accompanied by a lovely strip of our “bosque” forest of cottonwoods and the like – is a novel ecosystem, bearing only scant resemblance to the natural ecosystem before humans built dams and levees and diversions.

So also is the ditch network – a novel ecosystem, a tree-studded ribbon of green that spreads across much of the valley floor. Yes, a bit of cropland in there, but most of the green and the ecosystem is not that.

This is a far longer introduction than I had intended to a blog post pointing out a neat new piece of research by Frida Cital and colleagues at the Universidad Autónoma de Baja California in Mexicali. They looked at irrigation systems in the Mexicali Valley of the Colorado River Delta and found interesting ecosystem benefits (sorry, seems to be behind a paywall, but the abstract provides the gist):

These ES are fundamental in semiarid regions because of the intense land-use changes from riparian and desert ecosystems to irrigation lands, as well as water being diverted from natural streams to irrigation channels. This study highlights the importance of considering agricultural ditches as helpful, not only as a natural water treatment of agricultural pollutants, but also as providers of resident and migratory bird habitat and vegetation diversity and erosion regulation by sediment retention on desert agricultural valleys.

How do we use water in Albuquerque?

Albuquerque water use, via OpenET

I’ve been spending an inordinate amount of time the last few weeks pointing and clicking on the new OpenET project’s “data explorer”.

Using satellite data and magical algorithms, OpenET allows me to look at an arbitrary bit of land and retrieve an estimate of the amount of “evapotranspiration” – essentially outdoor water use – for recent years.

How green is Albuquerque’s Country Club golf course? How does the water use in the relatively affluent valley floor communities of Los Ranchos de Albuquerque and Corrales compare to the less affluent Atrisco and points to the south in what we call the “South Valley”?

Data wise, we have a pretty good handle on how much water Albuquerque’s largest municipal provider, the Albuquerque Bernalillo County Water Utility Authority, is delivering to customers each year, and how much of that water is returned to the river from the southside sewage treatment plant. But sometimes when I look at their data, I feel like I’m trapped in the old joke where I’m drunk and looking for my keys under a streetlight. (“Is that where you lost them?” someone asks me. “No, but it’s the only place where there’s any light!”)

Domestic wells (green dots) in Los Ranchos de Albuquerque

Consider, by way of example, a patch of Los Ranchos I’ve been looking at for a while as I try to make sense of Albuquerque water use. I’ve been drawn to Los Ranchos because its one of the greenest places in our desert city. In addition to municipal water for indoor use, which is metered, many of the homes have access to irrigation ditch water (and a tax break if they put that water to agricultural use). Irrigation delivery here is not metered. Many of the homes also have domestic wells drilled into the shallow aquifer, which are also generally not metered.

So, in summary – super green there, looks like people are using a lot of water. How much? We don’t know, it’s beyond my streetlight!

Enter OpenET, which allows one to highlight a polygon on a map and spit out consumptive water use, by month, back to 2016.

My little OpenET Los Ranchos test plot is about 450 acres between Rio Grande boulevard and the river, stretching between Montaño Road and the northern edge of a leafy be-lawned neighborhood called Tinnin Farms. This area of Los Ranchos is one of the more affluent areas in the greater Albuquerque metro area. By my rough “danger Fleck doing OpenET math” calculation, consumptive use of water added to landscapes in this area (above and beyond precipitation) amounted to about 1,300 acre feet of water last year.

Who gets to use what water?

In one of the papers I’m always pushing on my students, the late Elinor Ostrom highlights a set of key characteristics – “design principles”, she calls them – of successful common pool resource management regimes. Ostrom is importantly not arguing for any particular best solution to these problems. (The paper’s title is “Why Do We Need to Protect Institutional Diversity“.) But in her lifetime of work, the Nobel laureate identified key stuff that tends to show up in places where people have succeeded at the challenge of sharing a limited resource to maximize its benefits to a community.

Ostrom’s design principles ask a bunch of useful questions, and I’d like to paraphrase as they apply to my little toy example: who will be allowed to use what amounts of water, and when? How will rules over this use be monitored and enforced, and how will conflicts be resolved?

I would argue that in my little Albuquerque Rio Grande valley floor neighborhood, we lack a full set of these tools. We have one set of rules for irrigation water, a second set of rules for municipal water, and a third set of rules for domestic wells. For most of this, we lack enforcement mechanisms or fail to use those that the law might allow. The three management rulesets do interconnect in technical legal ways that might allow them to be integrated into a single management approach. Also, unicorns would be so cool!

In my book Water is For Fighting Over (not), I spent a good deal of time on what I think is one of Ostrom’s most important points – the need for a shared understanding of what the resource is and how it is being used. In her thesis work, she tackled the development of shared water management institutions in a place prosaically called “West Basin” west of downtown Los Angeles:

To solve a common pool resource problem, you first need a shared understanding of what the resource is. This sounds simple, but in the case of the West Basin, it was not.

This is one of the most important pieces of my Colorado River work – why my favorite basin peeps all seem to have these amazing collections of spreadsheets on their hard drives that they use to help sort out questions. But that’s one of those “drunk looking for keys under the streetlight” things. One of the reasons I love working on Colorado River issues so much more than the Rio Grande is because there’s so much more light!

This is why I’m so excited about OpenET. If it works – which means both that it has to be technically solid and also earn our trust – it can shed some of the light I think we need.

 

New Mexico state engineer John D’Antonio stepping down, cites lack of state support for agency

Per Dan McKay and Theresa Davis at the Albuquerque Journal, New Mexico State Engineer John D’Antonio is stepping down.

In doing so, he was sharply critical of New Mexico Gov. Michelle Lujan Grisham’s decision to not ask the New Mexico legislature for increased funding for his depleted department despite booming state revenue:

[H]e cited a persistent lack of financial resources for the Office of the State Engineer and unfunded mandates as factors in his resignation. He expects several senior staff members who are eligible for retirement to announce departures, too.

“We’ve taken the agency as far as we can, given the current agency staffing level and funding resources,” D’Antonio said.

The agency, he said, has the equivalent of 67 fewer employees now than it did under then-Gov. Bill Richardson a decade ago, when D’Antonio served an earlier stint as State Engineer. But his office was still directed to submit a flat budget this year, he said, amid strong growth in projected state revenue.

 

Watch Live: Tipping Point – The Colorado River Basin

I’m heading to Phoenix tomorrow (Wed. Nov. 10) to appear on what I hope will be a useful PBS Newshour live event:

The Colorado River runs nearly fifteen hundred miles, winding through seven states and Mexico. It supplies drinking water to nearly 40 million people, irrigates nearly 4 million acres of farmland and attracts millions of nature lovers to scenic Grand Canyon vistas.

And it is on the brink.

A 20 year mega-drought — exacerbated by climate change — is squeezing the Colorado dry. It’s a crisis for the people of the Southwest and a “canary in the coal mine” for us all.

Join PBS NewsHour’s Miles O’Brien for a special hour-long live event exploring the relationship between climate change and the fate of the Colorado River Basin.

Hosted live from Phoenix, the program will foster a solutions-based dialog with leaders in areas of science, agriculture, municipal water, Native American communities and conservation.

Scaling back, even more, in the Lower Colorado River Basin

With the ink barely dry on the ill-named Colorado River “Drought Contingency Plan”, the Lower Basin states (Nevada, Arizona, and California) are already cooking up a Plan C for even deeper reductions. Joanna Allhands at the Arizona Republic has a nice look at what we know about the details:

Arizona, California and Nevada are moving forward with a plan to save another 500,000 acre-feet of water in Lake Mead annually until 2026.

We’re talking 500,000 acre-feet over and above the mandatory cuts that are spelled out in the 2019 Drought Contingency Plan (DCP). Each year. For five years.

Just to keep the lake from tanking.

Allhands does a nice job of going past the sketchy details made public in a webinar last week, but the sketchiness of the details is in part the deal itself, rather than what we know about the detail. We’re repairing the locomotive here in real time while it’s moving down the track.

Expect the federal government to kick some money to fund the water use reductions, along with the Southern Nevada Water Authority, the state of Arizona, the Central Arizona Project, and the Metropolitan Water District of Southern California. Importantly, you can expect MWD – California – to kick in water. Details are still being worked out, but the participants were confidence enough to go public with what they’ve got.

We’ll learn more as the various agency boards begin taking up their parts of the deal in coming weeks.

I’m curious when we might see some sort of similar initiative on the part of the states of the Upper Colorado River Basin.

The stray calf of Peña Blanca

Cochiti Main Canal, just south of Peña Blanca, New Mexico. Oct. 30, 2021

Peña Blanca, NM – The Cochiti Main, winding through the village of Peña Blanca, was still flowing Saturday morning with some of the last of this year’s irrigation water destined for farms to the south.

I’m a bit jammed up in my effort to return to writing (see below for the “some personal news” portion of the post), so I loaded up a bike Saturday morning and drove north to what we might describe as one of the key “field areas” for The New Book.

Peña Blanca is an old Spanish village wedged between the indigenous communities of Cochiti Pueblo to the North and Kewa (formerly called by some Santo Domingo) Pueblo to the south. I’m actually far more interested in Cochiti and Kewa, but as sovereign nations they’ve closed down access during the pandemic, and a bike ride is a bike ride. So Peña Blanca it was.

The stray cow of
Peña Blanca. Photo by John Fleck, October 2021

Turning down Abrevadero Road I crossed the Cochiti Main and dropped down past alfalfa fields to the source of the day’s minor drama – a firefighter from nearby Cochiti on the phone trying find the owner of a stray black calf wandering on a street that is actually named (I do not kid in such matters) “Acequia Road”. The firefighter smiled at me as I rode slowly past, the calf gave but a brief glance before going back to doing calf things.

There is evidence here for my frequent claim that I am a “city kid”. When I explained to a friend, who grew up around manure, that it was my first such encounter in many years of cycling, he expressed surprise. But my city kidness is an empirical observation. I am comfortable asserting that I have never in my life lived within a mile of a cow.

According to historian Jacobo Baca, Peña Blanca in its modern form dates to a 1754 land grant by New Mexico Gov. Francisco Antonio Marín del Valle to Juan Montes Vigil. I say “modern” because the people of Cochiti Pueblo immediately to the north have occupied the area for what we like to call “time immemorial” – a time beyond the reach of memory, in some sense forever.

In the human history of this place, 1754 is the recent past.

It’s fair to say the land tenure in this area, like much of the Rio Grande Valley, is and has been a deeply contested thing, and I do not claim the expertise or standing to explain it here. Suffice to say the Pueblo communities have a robust history of contesting colonizers on their land, sometimes successfully, sometimes not, and some of the most interesting of those struggles have happened here.

Cochiti Dam. From Paul Blanchard, USGS

Cochiti,  Peña Blanca, and Kewa represent the Rio Grande’s introduction to what we in New Mexico call “the Middle Rio Grande”. The river once opened out of White Rock Canyon and spread across a widening valley floor – a beginning now dramatically and importantly inundated behind Cochiti Dam. Today a “recreation pool” floods the “time immemorial” summer homes of the Cochiti people. As I said above, the Pueblo people’s contestation of colonization has sometimes been successful and sometimes not. Cochiti Dam is one of the “nots”.

Today, rather than the graceful widening of a river slowing to meet its valley, we’re left with a concrete spigot at the base of a huge earthen dam.

Cultural implications aside, on purely water engineering grounds Cochiti Dam is some crazy shit. It runs nearly four miles from northwest southeast, plugging the Rio Grande, before making a sharp right turn for another mile to block the Santa Fe River. When they began storing water behind the dam in 1973, it raised the water table so much that the Santa Fe River downstream from the dam, once intermittent, became a perennial stream. The dam turned land on the valley floor, which the people to Cochiti had farmed for time immemorial, into a swamp.

It is impossible to understand the relationship between the Middle Valley and its river without coming to terms – hydrologically, institutionally, culturally – with Cochiti Dam.

Some personal news

bookshelf at the new office

I sorta quasi-officially finished up my five years’ tenure as director of the University of New Mexico Water Resources Program Oct. 22. I’m still helping the new director, Scott Verhines, with the transition and still teaching. But also undertaking the mental shift to the next thing.

I’m returning to a title and gig I had while I was writing Book Two – “Writer in Residence”, this time based at the Utton Center, a water policy group at the University of New Mexico School of Law.

The new office comes fully equipped with its own copy of Ira Clark’s Water in New Mexico, and I brought over the unkillable house plant (Sansevieria trifasciata) that Lissa gave me when I first moved into my last “writer in residence” office in the UNM Economics Department building. I’ve come close, but haven’t killed it yet, though I am happy to report that Utton Center Director Adrian Oglesby has offered to help water it.

I have found the restroom, and am making a leisurely task of becoming acquainted with the law school’s remarkable art collection.

The new gig is a chance to more fully focus on the thing that gives me joy – writing about water.

The WRP directorship was an awesome experience – working with grad students was definitely joyful. But it left me less time than I would have liked to think and write. (I guess I did write Book Three during my time as WRP director? But y’all know that Eric did most of the work, right?)

The New Book

This blog is my sketchbook. Writing in private has never worked for me – a craft honed by a life writing for newspapers is a craft that has public execution at its heart. I say that by way of explanation that, while the stray cow of Peña Blanca will almost certainly not be in The New Book, the challenge posed by making sense of Cochiti Dam might be at the book’s core.

It is reasonable to think that it was here, just downstream from the confluence of the Rio Santa Fe and the Rio Grande, that John Van Dyke, whose ideas are likely to play a role in the book, first encountered the desert river valleys that were at the heart of his strange and wonderful book The Desert. Standing off by the side of the road at Cochiti Elementary School Saturday morning, seeing the dam’s sweeping form as it dog-legged across the Santa Fe – that’s why I go to places, and then write about them.

After the Rio Grande ripped through Albuquerque in the flood of 1941, it is easy to understand the motivation of the dam-builders. If Cochiti Dam is the middle valley’s great sin, we must also consider whether the dam was some sort of salvation.

My co-author Bob Berrens and I are still not quite sure how to explain what the new book is about, but we’ll get there.

More sketches to come.

Udall: Greater streamflow declines in the southern part of the Colorado River Basin

Heather Sackett did a good story this week on new data Brad Udall has been sharing that geographically parses the declines in streamflow across the Colorado River Basin. For folks like us down here in New Mexico, dependent on the San Juan as a critical source of supply, the news is not good:

This month, Brad Udall, senior water and climate research scientist at Colorado State University, presented data that shows when comparing records from the past 20 years to those from most of the 20th century, rivers in the southern half of the upper Colorado River basin have lost a larger percentage of flows than rivers in the northern part of the basin.

For example, flows on the San Juan River near Bluff, Utah, have declined by 30% and flows on the Dolores River near Cisco, Utah, have declined by 21%. Flows on the Yampa River near Maybell and the Colorado River near Glenwood Springs have each lost just 6% of flows.

“We do think it’s going to dry more in the south and less in the north and we should at some point see a gradient, and sure enough, that has popped up at some of these gauges,” Udall said.

October 2021 Colorado River 24-Month Studies Shift to a More Realistic, but Troubling Future for Lakes Mead and Powell

A shrinking Lake Powell

By Eric Kuhn

The latest Bureau of Reclamation monthly Colorado River modeling runs show an even bigger drop over the next year in Lake Powell’s elevation that previously projected. But this is not an example of bad news getting worse. Instead, a change toward a drier baseline hydrology more accurately reflects the drying of the Colorado River basin in the 21st century.

Usually, during the non-snow accumulation and non-run-off forecast seasons (August – December), the Bureau of Reclamation’s 24-month studies change very little from month to month. Today, however, the basin’s nerds (I’m on that list) that closely follow these studies were in for a sobering surprise. All three of the October studies (most probable, minimum probable, and maximum probable) showed a consistent shift to a drier future. The reason for this shift is disclosed in footnote #1 – “The October 2021 24-Month Study includes the Colorado Basin River Forecast Center shift to the 1991-2020 period of record.”  In simple terms, out are the wet years from the 1980s and in are the more recent dry years from the 2010s.

This shift to the more recent years is important for several reasons. First, the 1991 -2020 period is likely to be much more representative of the future under climate change driven aridification of the basin.  Second, given the depleted state of the system reservoirs, seemingly small changes in storage can have big operational impacts. For example, the September most probable study showed Lake Powell ending Water Year 2022 at elevation 3545’, the October most probable study now shows elevation 3534’. The change is only 11’, but it’s enough to push Lake Powell into the Lower Elevation Balancing Tier for 2023. This means that the projected most probable release from Glen Canyon Dam for Water Year 2023 has gone up from 7.48 maf to 7.818 maf. When Lake Powell is in this bottom tier, the goal is to release between 7 and 9.5 maf/year so as to equalize end of water year storage between Powell and Mead.

For another example, look at the minimum probable studies. The September version shows Lake Powell bottoming out at 3482’ while in the October version it’s 3467’.  Again, only a 15’ difference, but since the minimum power elevation is 3490’ it has a big impact on how long the power plant will be unable to produce power. Which in turn has an enormous impact on the Upper Basin Fund cash flow.  The September minimum probable showed Glen Canyon Dam not producing power for about 21/2 months. See the graph below, under the October version a Glen Canyon Dam power plant outage could be as long as ten months (if not all year).  From a cash flow perspective, the difference is about $200 million.

The shift in the period of record traditionally only happens once per decade. It is a good thing it happened this year. Given what we’ve seen over the last 20 years, the shift will add needed conservatism and urgency to the Basin’s efforts to bring our water use in balance with the available supply.

What might planning for an 11 million acre foot or 10 million acre foot Colorado River look like?

One of the central questions dimly visible in the early discussions around the upcoming renegotiation of the Colorado River’s water operations and allocations rules is the question of how bad a “worst case” scenario should be considered.

This is crucial, because it constrains what sort of questions must then be confronted. The lower the future flows considered, the more likely it is that the negotiators will have to stare down the third rail question of how much water the Upper Basin can delivery hydrologically, and must deliver legally, at Lee Ferry, the dividing point between the Upper and Lower Basins.

For the century since the Colorado River Compact was signed, we’ve avoided dealing with that central question – what happens if the river’s flows are so low that the Upper Basin cannot deliver the 7.5 million acre feet per year (or 8.25 million acre feet, we can’t even agree about which number to argue about) contemplated by the compact’s Article III.

This question is so untouchable that in work done for the 2012 Basin Study, the Bureau of Reclamation’s modelers famously added what came to be called “miracle water” at Lee Ferry every time one of their model runs dropped below the threshold that might have otherwise triggered this legal argument.

Under the low flows possible under climate change, we face a stark choice – either we reduce the Upper Basin’s Lee Ferry deliveries below 7.5/8.25 maf, or we will have to curtail existing Upper Basin uses. Advocates of modeling such low flows in the planning scenarios are essentially saying – Let’s have that conversation now.

At the tale end of yesterday’s (Friday 10/15/2021) House Natural Resources Sucommittee on Water, Oceans, and Wildlife, it was California Rep. Jim Costa, a congressman from outside the Colorado River Basin, who asked the question pointed at the heart of the matter – how do we redo water allocations that make no sense in a river much smaller than contemplated in our hallowed Law of the River?

He was addressing a panel of representatives from each of the Colorado River Basin states (his comments start around 2:30 here):

The Law of the River and the quantification of the Upper and Lower Basin states amounted to some 17 million acre feet of water that was determined at that time was the annual flow of the Colorado River, and we know that in the last two decades its been more like 12.4 million acre feet, and that doesn’t account for other Native American tribes that have reserved water right claims that have yet to be resolved. So there’s just a tremendous amount of demand. And with climate change, we know the yield is only going to decline.

This is the question I’d like to submit to all of you, and if you want to provide written statement to your answer I think we would appreciate that.

Let’s say the annual yield over the next 30 years is 10 million acre feet. I don’t know, with climate change, maybe it’s plus or minus. How do we take into account how we got to the original allocation, with the Upper and Lower Basin States and the Native tribes, the sovereign nations, and then reallocate that on a lot less water.

At this point all we can see through the public windows into discussions about next-step Colorado River management guidelines is shadow boxing on this question.

But testimony yesterday from Southern Nevada’s John Entsminger suggests the public shadowboxing we’re seeing on this question is representative of disagreements in the private discussions. (I quote here from John’s written testimony.)

Despite the fervent warnings from internationally renowned scientists like Jonathan Overpeck and Brad Udall that urge us to plan for a future with even less than 12.3 million acre-feet, the river community is far from consensus about how dry of a future to plan for. And, while this panel was asked to talk about drought, on-the-ground evidence suggests the Colorado River basin is not experiencing drought but aridification – a permanent transition to a drier future. If we are to build upon the river’s many successes over the last 25 years, we must confront the magnitude of the challenge in front of us and quickly reach agreement on what future scenario we’re willing to plan for. (emphasis added)

Speaking two weeks ago at this year’s Getches-Wilkinson Center conference in Boulder, Entsminger put a number to Southern Nevada’s thinking. In the next iteration of its long range water resources plan, Entsminger’s Southern Nevada Water Authority will include a “what if” planning scenario for how the agency would deal with an 11 million acre foot per year Colorado River. This is not to say that Southern Nevada expects an 11 million acre foot river, but rather than it believes it needs to have a plan in place should that happen.

I could be wrong, but so far I’ve seen no public evidence that any of the states of the Upper Basin are willing to entertain flows that low in the planning scenarios to be considered in the modeling done to support the upcoming negotiations. I look forward to seeing the written answers the basin states’ representatives submit to Costa’s question.

 

The challenge of meeting a legal and moral obligation to Colorado River Basin tribes

At last week’s Getches-Wilkinson Center conference in Boulder, attorney Jay Weiner, who represents tribes (but was careful to say he was not speaking on any particular tribe’s behalf) made an important point, which is repeated in this excellent piece by Mark Armao this week in Grist:

“The basin is free-riding off of undeveloped tribal water rights,” said Jay Weiner, an attorney for the Quechan Indian Tribe. Weiner said there is a “fundamental tension” between tribes’ desire to fully develop their water rights and the overarching need for everyone in the basin to consume less water overall.