The Unique Mojave Desert Oasis at the Center of the Cadiz Controversy
"Hey, there are tadpoles here.” A few feet ahead of me on the trail, David Lamfrom takes a wide step over a pool of water, his boot coming down on a few three-square bulrush stems on the other bank.
Sure enough, the tiny puddle is full of wriggling young amphibians. Red-spotted toads, probably, or maybe Baja California treefrogs. I’m no expert. I kneel to watch them for a moment. They seem out of place here. All around us is some of the driest desert in North America. The vanished settlement of Bagdad, about 30 miles west of here, holds the American record for the longest interval without any precipitation at all: 767 days between October 1912 and November 1914.
And yet here, on the desiccated, sun baked south face of the Clipper Mountains, is a half-mile-long grove of thirsty willows and cottonwoods with tadpole-filled pools at their feet. Bonanza Spring.
I stand back up, and hustle to catch up with Lamfrom, who has followed a faint path through the willow and tules. We walk uphill to a small ridge, which gives us a view of the whole upper part of the spring. Beyond, in all directions, lies the spectacular and arid Mojave Desert, millions of acres of landscape that hasn’t seen standing water since the days of the sabertoothed cats. “This is the only water source of its size in more than 1,000 square miles of desert,” says Lamfrom.
He doesn’t actually say “it’d be a shame if something happened to it” out loud, but we’re both thinking it.
Lamfrom is Director of the California Desert and National Wildlife programs for the National Parks Conservation Association (NPCA). He and I are exploring Bonanza Spring partly to get out into the desert on a fine cool Friday afternoon in May, but mainly because there is indeed something that may happen to this unlikely desert oasis in the heart of the Mojave Trails National Monument.
That something is just out of sight from where we stand, tucked down behind a low ridge to the south, about 11 miles south and 1,200 feet downhill.
The company Cadiz, Inc., which intends to pump up to 50,000 acre-feet of water each year from its property on the other side of that low ridge, has maintained for more than a decade that Bonanza Spring and other springs throughout this part of the Mojave won’t be affected by their pumping. Cadiz wants to sell the water to a handful of Southern California water companies, who would provide it to their lawn-sprinkling, driveway-car-washing, sidewalk-hosing clientele in Orange County and elsewhere.
“According to extensive scientific analysis,” Cadiz claims in a July 2015 post on its website,
“...there is no physical hydrologic connection between the springs in the upper elevations of the watershed and the groundwater stored in the alluvial aquifer beneath the Project area. As a result, pumping water from the aquifer system beneath the Project area, miles away and deep below ground surface, could not harm the springs.“
That assessment is not universally accepted.
When you pump water out of the ground the water table at the pump site tends to drop, and it falls more the more water you remove. Water in surrounding parts of the aquifer will flow toward the pump due to the pull of gravity, lowering the water table in those surrounding areas. Groundwater even farther from the pump will flow into those portions of the aquifer, and so on. The result, if the pump is drawing water from the aquifer faster than nature replenishes it, is a water table that sinks the closer it gets to the pump, a phenomenon scientists refer to as a “cone of depression.”
If the groundwater at the Cadiz pump site is connected to the aquifer that supplies Bonanza Spring, then a spreading cone of depression could actually lower the water table at the spring, potentially drying it up.
Cadiz has committed to monitoring water levels at Bonanza Spring, which sounds reassuring. But if the aquifers do turn out to be connected, by the time the cone of depression reaches Bonanza Spring enough to lower water levels there, that damage will be well underway. Even stopping pumping altogether might not keep the spring from drying up for many years afterward. And that could hurt not just the descendants of these tadpoles, but bighorn and deer and migrating neotropical birds and all the other wildlife that depends on this oasis.
Cadiz’s contention that Bonanza Spring is not hydrologically connected to its proposed wells is actually presented in the project’s Final Environmental Impact Statement as just one of two potential models of how the area’s groundwater might work. The second model, which assumes that the aquifer at Bonanza Spring is connected to the aquifer from which Cadiz would pump its water, suggests that the water table at the spring might drop by several feet depending on how much precipitation actually falls in the Clipper Range to replenish the local aquifer. Estimates of that “fluctuation” range around one and a half feet after the project life span — enough to dry up most of Bonanza Spring — to 6.5 feet within 450 years.
As the Oakland-based water think-tank The Pacific Institute observed in its 2012 comments on Cadiz’s Draft Environmental Impact Report, though there was no solid evidence that the aquifers feeding Bonanza Spring and the Cadiz wells were linked, going on to assume there was therefore no connection between them was committing a logical blunder so old that it has its own catchphrase: “Absence of evidence is not evidence of absence.” Being unable so far to detect a connection doesn’t mean there is no connection.
There are tadpoles here. How did that happen? Regardless of their species, frogs and toads don't travel far from water sources in the California deserts. Though there are plenty of springs dotted across the desert, the arid expanses that separate them pose certain death for any hapless frog that decides to travel from one spring to the next. These tadpoles and their descendants will either survive at Bonanza Spring or perish at Bonanza Spring, with little hope of escape should the spring cease to flow.
And yet you can find toads and treefrogs at springs and other permanent water sources across the Mojave, a constellation of scattered populations isolated from one another. How did they get there?
There are frogs and toads at most springs in the Mojave. How did they get there?
Some of them may descend from ancestors put there deliberately by people over the centuries, or whose eggs caught improbable rides on passing birds. But the most likely scenario is that the tadpoles at Bonanza Spring, and at other springs across the desert, descend from ancestors who got there on their own thousands of years ago, when the Mojave was very different.
Up until around 12,000 years ago, there was no Mojave Desert as we know it today, In its place was a better-watered landscape, valleys and low hills forested with juniper, live oak, Joshua tree and piñon, with freshwater lakes occupying the lowest parts of valleys.
Across the slopes of mountain ranges like the Clippers, the relatively abundant rainfall fed not only a wealth of springs and streams, but forests of white fir reaching below 4,000 feet in elevation.
That's plenty of hospitable habitat for frogs and toads, which were likely widespread across the landscape, living in the shadow of dire wolves, ground sloths, and sabertoothed cats. Scientists have found amphibian fossils in the soil of the Cadiz Valley, near the extinct railroad siding town of Archer about 18 miles south of Bonanza Spring, where today even the sturdiest, desert-adapted spadefoot toad would not survive for long.
About 12,000 years ago the climate began to change. The Mojave got drier and hotter. Lakes began to dry up. Streams disappeared, as did most of the springs. The forests retreated upslope. By 8,000 years ago, the Mojave was much as we know it today: arid mountain ranges with piñon-juniper forests above 5,500 feet, wide expanses of dry separating a few scattered springs, and huge expanses of saline dust that desert residents persist in calling "lakes." As the desert dried out in a geologic eye-blink, the ancestors of today's red-spotted toads and Baja California treefrogs saw their habitat shrink and fragment, eventually consisting of just a few tolerably moist spots here and there, like Bonanza Spring.
But before that, for at least two million years, the Mojave went through one epoch after another of abundant water, rain and snow feeding forests that allowed water to seep steadily into the ground. There, that Pleistocene precipitation filled the Mojave's huge aquifers with what we now call "fossil water," millions of acre-feet of groundwater locked away in deep aquifers, coming to the surface only here and there and hardly refilled by the modern era's stingy rains.
Much of the controversy surrounding Cadiz can be summed up this way: Will Cadiz be pumping this fossil water to end users in Southern California suburbs, or will the water Cadiz supplies have fallen in the Mojave sometime in the last couple thousand years? And either way, how long will our stingy modern rains take to replenish the 50,000 acre-feet per year Cadiz would sell?
The annual amount of water that actually recharges the aquifer underlying the Cadiz Valley is highly contentious. Estimates of range from around 5,000 acre-feet to 33,000 acre-feet. As The Pacific Institute observed in its 2012 comments,
It is of note that most of the high recharge estimates… have been commissioned by Cadiz and done in support of the project.
The topic hasn’t gotten any less controversial in the five years since, which makes sense when you consider how little rain hits Cadiz's watershed. That watershed is around 1,100 square miles, and annual rainfall is in the neighborhood of 2.7 inches per year. In order for 32,000 acre-feet of water to replenish the aquifer in an average year, fully one fifth of all the water that falls in the watershed would need to make it to the aquifer. That's not physically impossible, but given the quickness with which fallen rain evaporates back into the air, and the adeptness with which desert plants seek out every last drop of available soil water for their own use, it seems unlikely on the face of it.
32,000 acre-feet per year also works out to 44 cubic feet of water per second, a flow 130 percent of that of the Los Angeles River at Sepulveda Dam at this writing, after a very wet winter.
Gut impressions don't make for good science, but scientists do have very different estimates of how quickly the aquifer is recharged, and most of them are much more conservative than those of Cadiz, Inc.
During the 2012 comment period on Cadiz's Draft EIR, NPCA and the Center for Biological Diversity hired Sausalito hydrologist John Bredehoeft to assess the likely actual recharge of the aquifer. In his comments on the Draft EIR, Bredehoeft concluded:
"The recharge estimate of 32,000 ac-ft/yr appears to be too high, especially when one considers the evaporation rates on the Bristol and Cadiz dry lake playas must equal the recharge. A recharge rate in the range of the other two considered in the DEIR, 16,000 and 5,000 ac-ft/yr, seems much more likely. "
One could reasonably point out that if we cast a critical eye on the estimates of scientists hired by Cadiz, it's only fair to cast that same critical eye on scientists hired by Cadiz's opponents.
“None of the water we are going to take fell on the earth in the last 100 years. This is millennial water."Cadiz CEO Scott Slater as quoted in Wired, January 7 2016
As it happens, there is a team of hydrologists not paid directly by either side that has assessed the state of water in the Cadiz region. In May, U.S. Senator Dianne Feinstein challenged — not for the first time — Cadiz’s figures on how quickly the aquifer would recover from the pumping, citing a letter she’d received from the U.S. Geological Survey. In that letter, USGS Acting Director William Werkheiser referred to an earlier assessment from February, 2000 in which USGS estimated recharge rates for Cadiz’s entire watershed that ranged from 5,000-10,000 acre feet per year — way under Cadiz’s preferred estimate of around 32,000 annual acre-feet, and significantly lower than Bredehoeft's upper estimate of 16,000. In other words, according to the USGS, Cadiz’s recharge estimates were at least three times, and possibly six times, too optimistic.
In the letter, Werkheiser told Feinstein that “We are not aware of new information that would change our recharge estimates.” However, with an eye toward that “Absence of Evidence” axiom, Werkheiser conceded that there may be newer studies that his agency hadn’t seen that would support Cadiz’s claims.
It would make sense to give the nation’s premier public hydrology agency a crack at the data, to see if a rigorous independent assessment bears up Cadiz’s claims. But that can only happen if Cadiz’s project triggers a federal environmental review under the National Environmental Policy Act (NEPA).
Cadiz has been adroit at crafting its project so as not to require that federal review. The project’s weak point, a pipeline in a railroad right-of-way across public lands that would link Cadiz wells to the Metropolitan Water District’s aqueduct, almost tripped the company up last year when the Bureau of Land Management ruled the pipeline route couldn’t be used without NEPA review.
That ruling was reversed shortly after Donald Trump’s inauguration. And in the same month in which Senator Feinstein released her correspondence with the USGS, the Senate was considering whether to confirm longtime Cadiz ally David Bernhardt for the position of Deputy Interior Secretary. If confirmed, Bernhardt would be able to smooth the way for Cadiz to a considerable degree. Bernhardt is a partner at the law firm Brownstein Hyatt Farber Schreck, which Cadiz has paid $2.75 million and 200,000 shares of stock in exchange for lobbying services.
It comes down to this: unless some really inconvenient fact shows up that monkeywrenches the project, Cadiz is looking more and more like a done deal. And we may only find out what effect the project has on the desert when it’s already too late to stop the damage to Bonanza Spring, where the heirs of a wetter Mojave still hold on to life, for now.