Why, in 1928, the Bureau of Reclamation treated Mexico as part of the Colorado River Basin

A guest post by historian Sara A. Porterfield, Ph.D. Candidate, University of Colorado at Boulder

Modern USBR map

As I was working on a draft of my dissertation’s introduction a couple months ago, I decided that I HAD to know what percentage of the Colorado River Basin lies in Mexico. This factoid would have taken up half of a sentence and wasn’t necessary to my argument or larger purpose, but I was probably subconsciously (ok, consciously) looking for a way to procrastinate tackling the larger issues of the introduction, like formulating my argument. I put this question out to the #CORiver Twitterverse, and John, Abby Burk (of the Audubon Society), and I started an email chain that went way, way down a Colorado River rabbit hole.

Somewhere in that email chain John sent along a 1928 map of the Colorado Basin that included Mexico, writing that he was “fascinated by what they were thinking about in 1928 that made them include it. It certainly was not a time during which we were cheerfully thinking about sharing water with Mexico.” I looked at the map and thought what was Mexico doing on that map? This sounded like a job for a historian!

1928 USBR map

I spent a little time looking at both the newer U.S. Bureau of Reclamation map that includes Mexico and the 1928 map John had sent me. Here’s my theory about why the Bureau would have included Mexico in their 1928 map.

The key to the 1928 map is what really got me thinking. There’s reservoir sites, national parks/monuments, and power projects listed, sure, but the only thing in the key that appears in the Mexican part of the Basin is the dark green of the private irrigated areas and the dark brown of the estimated irrigable areas.

This made me think that those making (or directing the making of) the 1928 map were far more concerned with irrigation potential than with geographic/hydrologic accuracy, as the modern map seems to take as its aim. The irrigation and potential irrigation marked on the 1928 map led me to that conclusion, as well as the fact that they extended the Basin to include the Salton Sink/Imperial Valley—which it doesn’t today.

Lower Colorado, from 1928 USBR map

So, after looking through my research database and not finding anything, I remembered the Fall-Davis Report, officially titled Problems of Imperial Valley and Vicinity and published in 1922.


The Basin map included in the Fall-Davis Report is almost identical in outline to the 1928 map from John. The Fall-Davis map is quite a bit simpler than the 1928 map and doesn’t seem to have the key/shading the 1928 map does—just a Basin outline with existing and potential irrigation and hydropower projects.

Fall-Davis Report map

The Fall-Davis Report advocated for the construction of two projects: Hoover Dam and an “All-American” Canal, and I think these two projects help us understand why the 1928 map and the Fall-Davis map were drawn the way they were. First, Imperial Valley irrigators and BuRec engineers wanted Hoover Dam (then called Boulder Dam) for flood control to protect irrigation in the delta region. The floods of 1905-1907 that tore out an Imperial Valley headgate and created the Salton Sea were a not too distant memory for Imperial Valley residents and Bureau engineers—and Davis and others in BuRec wanted to do everything in their power to prevent that from happening again. From this, I can see why they would have drawn the Basin to include the Salton Sink since the river could, conceivably, change course and flood the Imperial Valley again at any moment, thus destroying the booming agricultural industry there. Drawing the Salton Sink into the map made clear the threat of the river doing this again.

Second—and more to the point—I believe these maps include Mexico because the U.S. was worried about Mexico taking water out of the Alamo Canal on its way to the Imperial Valley. The geography of the eastern side of the Imperial Valley along the western bank of the Colorado was such that it was difficult to construct a canal due to a sea of sand dunes with a tendency to drift, so the original Imperial irrigators negotiated with Mexico to bring water to the Imperial Valley via the Alamo Cana. The Alamo took water out of the Colorado in Mexico, diverted it south of those pesky sand dunes, and then delivered the water to Imperial irrigators across the California line. Those irrigators worried that Mexican irrigators would try and steal “their” water on its way to their crops—and therefore advocated for an “All-American” Canal that would eliminate the need to bring water through Mexico (For more on this, see “Chapter 2: Imperial Joins the Crusade” in Norris Hundley’s Water and the West).


The 1928 map as well as the Fall-Davis map (to a lesser extent) included Mexico and its irrigated and potentially irrigated acreage in order to make the argument for the All-American Canal. Those making the maps—including BuRec bureaucrats and engineers and Imperial irrigators—wanted to scare legislators into thinking that Mexico could develop tens of thousands of acres of land with water “stolen” from the Alamo Canal. The Fall-Davis Report says as much: “The Imperial irrigation district contains more than 100,000 acres of irrigable land not yet irrigated and the same valley in Mexico can increase over 40,000 acres, and is in a physical position to take the necessary water from the Imperial [Alamo] Canal before it reaches the California line” (p. 6).

The BuRec didn’t include Mexico in its 1928 map out of the goodness of their heart or out of an allegiance to hydrologic accuracy, but because they wanted to shut down agriculture in the Mexican delta. What can seem like a cartographic anomaly—the inclusion of a portion of the Basin not seen until the twenty-first century popping up in an early-twentieth-century map—reveals the map makers’ motives, how the U.S. valued water, and the status of the nation’s diplomatic relationship with Mexico in that moment. These hidden histories uncover the Colorado’s past and help us understand more clearly the current dynamics at play in the Colorado Basin today.

– Sara Porterfield

The Cape Town lesson: avoiding apocalypse

The headline on this terrific Robyn Dixon piece in the LA Times about how Cape Town staved of a water supply catastrophe has created an unfortunate framing:

How Cape Town found water savings California never dreamed of

One frequent interpretation as it rocketed around water-interested social media was, “We’re pathetic, look how much better Cape Town did compared to us!”

But that’s not the right takeaway, I think. There’s a really important message embedded in this:

High-income Cape Town families have cut their average water use by 80%, according to Martine Visser, director of the Environmental Policy Research Unit at the University of Cape Town, while low-income families cut back by 40%. After city residents were restricted to just over 13 gallons per person a day, any household that blew the limit had a water restriction device attached to its pipes by authorities.

The extraordinary savings — in the heat of the Southern Hemisphere summer — put to shame how much water California used daily when its drought dragged into the summer of 2016: 109 gallons per person.

During the devastating 1996-2010 “Millennium Drought” in Brisbane, Australia, daily water use tumbled from 79 gallons per person to just 44 gallons. Impressive, but not as good as Cape Town.

In each case, the cutback is commensurate with the needed response to specific local conditions. In cutting back to 109 gpcd, Californians cut back to the levels needed to respond to their local water supply situations. Things were worse in Brisbane, so residents had to cut back farther. Things were really bad in Cape Town, so they had to cut back a lot.

The message is that, if the need is there, in these modern rich world settings we are able to dial back our water use a lot. The apocalypse is not nigh.

When people have less water, they use less water.


The Colorado River-Sacramento Delta Connection

With an 85 percent allocation of northern California water from California’s State Water Project last year, the Metropolitan Water District of Southern California was able to cut back on its use of Colorado River water, leaving more than 300,000 acre feet in Lake Mead. That water has provided a sufficient buffer than Mead will end this year at an elevation of 1,077 feet above sea level, barely above the threshold (1,075) at which a Lower Colorado River Basin shortage is declared, with enforced water use cutbacks in the Lower Basin.

California State Water Project, courtesy Wikimedia Commons

This year, with a current California State Water Project allocation of 20 percent, Met has far less wiggle room, less flexibility to leave water in Mead. In other words, problems in Northern California, in the supplies that flow through the Sacramento Delta to the State Water Project pumps, create risks for the Colorado River because of the interlocking nature of the two systems.

Met has a history in recent decades as a collaborative, positive participant in Colorado River governance. All else equal, Met has repeatedly shown a willingness to do the right thing for the Colorado River Basin as a whole. But it must first act to ensure the reliability of its own system supply.

This was the animating point of the talk I gave last week at the California Water Policy Conference at U.C. Davis. California is the 800 pound gorilla in the western water room. How it deals with the problem of moving water through the Sacramento Delta has a huge impact on the entire west. Success in ensuring reliability of delta supply to southern California decreases pressure on the Colorado River. Failure increases that pressure. Which is an overlong setup to my interest in this process, as Met considers picking up the full price tag for building two big tunnels beneath the delta. Via Ryan Sabalow:

Pushing ahead with an ambitious effort to take a majority stake in the state’s troubled $16.7 billion tunnels project, Southern California’s behemoth water agency announced Tuesday that the plan would cost its ratepayers less than $5 a month.

On Tuesday, staff at the Metropolitan Water District of Southern California told board members $4.80 was the most the 6.2 million households in Metropolitan’s service area could expect to pay if the agency moves ahead with plans to take on 65 percent of the share of building both tunnels.

One of the central points in the work of Elinor Ostrom, whose work animates a lot of my teaching in the UNM Water Resources Program, is the importance of the boundaries we draw around a resource problem. We tend to do it at the local or state level, awkwardly sometimes at the scale of river basins spanning two or more states, and only very awkwardly in a case like these were the resource system that matters spans two entirely different systems, connected via these giant canals that we built in the 20th century.

So I sit out here, two states away from Los Angeles, three states away from Sacramento, and watch California and fret.

New constraints on Imperial’s ability to throttle back Colorado River water use

I’ve been puzzling over the impact of Imperial Irrigation District’s legal struggle over its “Equitable Distribution Plan”, a regulatory framework for governing how much water individual farmers can use. This story from Daniel Rothberg is a big help:

As a practical matter, the repeal of the Equitable Distribution Plan lessened IID’s control over its plans to potentially store more Colorado River water in Lake Mead, which is a key part of California’s role in the Drought Contingency Plan.

“The absence of [an Equitable Distribution Plan] means that we lack a very important tool that has served us since 2013, and will certainly reverberate throughout the basin and among all the Colorado River water users,” Kevin Kelley, IID’s general manager, told the board on February 6….

Without the allocation system, IID’s water use is determined less by its elected board and the staff and more by the orders of agricultural users, which can vary. The ruling leaves the district with fewer management tools to control overruns and conservation.

Via Water Deeply, helpful throughout.


“breakdown” in Kirtland fuel spill cleanup

Albuquerque’s municipal water utility, in a strikingly worded memo yesterday, said the latest plans for managing a huge groundwater spill on and adjacent to Kirtland Air Force Base represent “a breakdown” in what was once a partnership among the water utility, the Air Force, and the New Mexico Environment Department.

The new plans back away from aggressive state-mandated efforts to clean up the spill, and weaken ongoing efforts to characterize the extent and seriousness of the contamination, according to the memo. According to the Water Utility, the new plans are “disconnected from the stated goal of protecting drinking water and the aquifer and undermine Water Authority’s ability to ensure the safety and quality of drinking water”:

contaminated groundwater spreading beneath Albuquerque

The spill, discovered in 1999 but likely dating to the 1950s, came from a long slow leak in an Air Force aviation fuel pipeline adjacent to the base runways. As you can see from the map, it has spread nearly a mile off of the base, moving beneath a southeast Albuquerque neighborhood. Because of its proximity to Albuquerque Bernalillo County Water Utility Authority drinking water wells, it is by far New Mexico’s most serious groundwater contamination problem.

A tense relationship between the ABCWUA, the Air Force, and state regulators had thawed in 2012-13, as the New Mexico Environment Department and the Air Force invited the Water Utility into the decision-making process. But the new memo, from the Water Utility’s Rick Shean (a graduate of the UNM Water Resources Program!), confirms what I and others have been hearing for some months – that the relationship has broken down.

This poses interesting governance questions that I’ve used as a case study in my new academic life. The Water Utility does not have legal standing as a regulator here – that role falls to the New Mexico Environment Department. But the Water Utility, especially under the leadership of Bernalillo County Commissioner Maggie Hart Stebbins and Water Utility Chief Operations Officer John Stomp, plays a critical role in looking out for the interests of the community. We made significant progress after the Air Force and NMED invited ABCWUA into the decision-making tent.

This issue is on the agenda for tonight’s (Wed. March 21, 2018) ABCWUA board meeting. 5 p.m. at the Council Chambers, Albuquerque City Hall building.

Palo Verde Irrigation District withdraws lawsuit against Metropolitan Water District of Southern California

In a bit of Colorado River detente, the Palo Verde Irrigation District has filed a motion in Riverside County Superior Court to withdraw a lawsuit it had filed against the Metropolitan Water District of Southern California over the use of water on Met-owned land in the Palo Verde District:


The move does not mean peace on the river between these two powerful water agencies, but it does at least create space for discussions, including a meeting scheduled for next Monday between leaders of the two organizations.

PVID filed the suit last year over its concerns about what Met was doing on land the municipal water agency owns in the rural agricultural district. PVID has been increasingly concerned that Met will scale back farming in the desert valley to send the saved water to folks in urban, coastal California. Met has repeatedly try to assure the Palo Verde community that its intention is to collaborate and support continued farming.

The suit was a minor legal skirmish, over California Environmental Quality Act issues rather than the underlying water rights and management questions – more of a shot by PVID across Met’s bow. The concerns at the heart of the dispute have not gone away, but will now be addressed in meetings and negotiation rather than litigation.

“For three days they traveled in the desert without finding water.”

On a bike ride this morning, I turned onto a little dirt trail through the woods, heading out toward the Rio Grande. Twenty yards from the river, I found a book lying in the trail, battered by the weather:

The book, later.

It was a Bible, lying open to Exodus 15:22: “Then Moses led Israel from the Red Sea and they went into the Desert of Shur. For three days they traveled in the desert without finding water.”

“When they came to Marah, they could not drink its water because it was bitter.”

Not sure what to make of this, other than to point out that the river is low, but they did eventually get to Elim:

Then they came to Elim, where there were twelve springs and seventy palm trees, and they camped there near the water.

I left it on the bench, with a stick to mark the page.

Water policy implications of elk, raiding wheat fields, in Polvadera, New Mexico

Agriculture in Socorro County, NM, courtesy USDA Cropscape

I had one of those “I wish I was still a reporter” moments when Glen Duggins, at yesterday’s meeting of the Middle Rio Grande Conservancy District board meeting, raised the issue of elk in Polvadera.

Polvadera is an unincorporated community along the Rio Grande, between the also unincorporated communities of San Acacia and Lemitar, strung out along the floor of the most productive farmland along this stretch of the river. Calling it “the most productive farmland” may be misleading, because the net cash farm income along this stretch of the river tends to be negative save for Socorro County. But this is not Iowa, and the sort of ag productivity numbers that shape the CBOT futures markets can’t tell us the full story of farming here. Which is why I perked up at the discussion of elk.

Duggins, a board member from Socorro County, had gotten a call from a constituent who was having trouble with elk raiding his wheat field. This is not large-scale agriculture we’re talking about. And the MRGCD is an irrigation, drainage, and flood control agency, not a game management agency. But the fact that it’s a very small farmer growing six acres of winter wheat to supplement his retirement income in some sense makes it all the more important, and sheds interesting light on questions of what water management and governance are really all about here in what we in New Mexico call “the middle Rio Grande valley”.

In my last job, as a newspaper reporter, I used to hang out at the MRGCD’s Monday afternoon board meetings when I could. It turns out that in my new job, as director of the University of New Mexico Water Resources Program, a couple of hours at the MRGCD board meeting also is time well spent. You get agency water manager David Gensler’s regular water reports – how much is in storage, when and where and how releases to the ditches for spring irrigation are progressing, and the important question in a dry year like this of how the summer season looks. Chuck DuMars, the former law professor who represents MRGCD (and many other important water agency clients, including California’s big Imperial Irrigation District), gives what often amounts to mini-seminars on the rich tapestry of New Mexico water law. Those are usually the main attractions for me.

But you also get governance at the retail level – complaints about which ditches are getting water when, the eternal discussion of ditch bank gates and public access, culvert repairs. And yesterday afternoon, elk.

Raids by elk onto the Socorro County valley floor have been an increasing problem over the last decades (yes, I wrote about this when I was at the newspaper – I’ve got links like this for many occasions!).

I am not a lawyer, but I’m pretty sure elk predation is not explicitly covered by MRGCD’s explicit statutory authorities. But in the midst of the hodgepodge of government entities whose duties encompass agriculture, MRGCD is arguably the most important. Socorro County’s human geography is defined by the narrow strip of green along the Rio Grande and the irrigation ditches that spread its water on the valley floor immediately surrounding it. The distribution of water both enables and constrains agriculture in all its forms in this part of the country, and therefore the place’s human habitation. So when the Polvadera farmer saw elk eating his supplemental retirement income, it was I guess natural to call Duggins. That is the importance of this story.

It’s not clear to me what a water agency can do about elk. But the MRGCD board’s Urban Affairs Committee pledged to look into it, there was a suggested field trip to check out the elk problem in person, and a charmingly lengthy discussion about ensuring that MRGCD staff with hunting experience and inclinations be included in the policy discussions of possible solutions to the Socorro County elk problem.

I love the pageant of democracy.

We should probably stop calling it “drought”

Colorado River Basin Managers are working on what they call a “Drought Contingency Plan” to reduce water use, but that’s probably a bad name to describe what’s going on, as the members of the Colorado River Research Group explain in a new white paper (pdf):

In current Colorado River water management, perhaps no word is used (and misused) more than drought. To most people, the word drought contains two concepts. The first is the lack of available water, primarily a function of below normal precipitation, but often exacerbated by management and water?use practices. Second is the notion that the condition is temporary—a deviation from a norm that is expected to eventually return. Aridity, in contrast, refers to a dryness that is permanent, and is a function of natural (and presumably stable) climatic conditions. While it is fair to say that the Colorado River Basin is in a period of drought (in that recent precipitation has lagged slightly below the long?term averages), and that much of the basin is arid (or semi?arid), neither term is adequate to accurately describe emerging conditions in the Colorado River Basin. For that, perhaps the best available term is aridification, which describes a period of transition to an increasingly water scarce environment—an evolving new baseline around which future extreme events (droughts and floods) will occur. Aridification, not drought, is the contingency that should guide the refinement of Colorado River management practices.

The underlying hydrologic problem is a decline in “runoff efficiency” – less water in the rivers for a given amount of rain or snow. That’s also the message in a new paper by the University of New Mexico’s Shaleene Chavarria and Dave Gutzler on the Rio Grande, where precipitation has actually gone up slightly, but river flows have nevertheless gone down.

Changes in the snowpack–runoff relationship are noticeable in hydrographs of mean monthly streamflow, but are most apparent in the changing ratios of precipitation (rain + snow, and SWE) to streamflow and in the declining fraction of runoff attributable to snowpack or winter precipitation.

So yeah, drought’s a less useful word. We don’t change language by publishing white papers and journal articles, but we can at least focus some energy on the conceptual problems.