A Lake By Mistake
© kim stringfellow 2005kim stringfellow2006_3_38-39
In the midst of the scorching Sonoran desert, where rainfall averages two to three inches per year, the Salton Sea seems impossible, a blue mirage. On closer inspection, the blueness is a mirage; the water is foamy and brown with algae. California’s largest lake nonetheless looks like a permanent feature of the desert landscape. So it comes as a surprise to many that this body of water was created 100 years ago by human error.
While the Salton Sea’s creation was an accident, the presence of a lake on the site is hardly unnatural. Bodies of water have been appearing and disappearing there for millennia. The Salton Sink is the lowest-lying portion of a rift valley aligned with the San Andreas Fault. Millions of years ago it was the head of the Gulf of California, before the silting of the Colorado River’s delta cut it off. Periodic overflows of the Colorado found their way into the basin to form lakes that were often much larger than today’s Salton Sea. These lakes would then dry up over the course of many years. The last time this happened seems to have been during the sixteenth century, but even after that, smaller floods continued. In 1891 an overflow spread across the trough to about half the extent of the present sea.
Dreams of making the Sonoran Desert bloom with Colorado River water go back at least to the mid-nineteenth century, shortly after Mexico ceded the Southwest to the United States. The main obstacle was topographical. An irrigation canal across California would be prohibitively expensive because of the formidable Algodones Dunes, which extend down just beyond the Mexican border. Arrangements with the Mexican government and land purchases in Mexico would be necessary to move water around the dunes through northern Baja California.
The trouble that would cause the Salton Sea to come into existence started when the first serious effort to settle the desert began, in 1896. It was led by Charles R. Rockwood, an engineer who had spent time with the U.S. Reclamation Service, and his newly organized California Development Company. CDC was severely undercapitalized, so in 1900 Rockwood brought in a respected Los Angeles engineer, George Chaffey, who offered to raise $150,000 to build a network of canals. The canals would supply 400,000 acre-feet (that is, enough to cover 400,000 acres to a depth of one foot) of water per year to the parched flatlands south of the Salton Sink. Chaffey agreed to supervise the project in exchange for being given control of the virtually bankrupt company for five years. He also hoped make money with a separate company that would develop land in the valley; CDC was in the water-supply business only.
Chaffey placed the intake for his new canal system below Pilot Knob, a promontory on the California side of the river opposite Yuma, Arizona, and just north of the boundary with Mexico. Water began moving in May 1901 toward what would soon be named the Imperial Valley. Workers built a 40-mile-long canal across the Mexican border and back, using natural channels cut by the Colorado’s previous overflows for part of the distance. By April 1902 farmers’ cooperatives had dug 400 miles of irrigation ditches, enough to supply 100,000 acres of land.
Flow in the gravity-fed canal was controlled with a headgate a short distance downstream from the source, at a site called Hanlon Heading. The headgate, a simple A-frame structure of rot-resistant redwood, 15 feet high by 70 feet long, was meant to be temporary. The flow was governed by wooden flashboards, which extended above the top of the gate. Water ran over them, as in a spillway.
Financing remained precarious for CDC, especially after the U.S. Department of Agriculture issued a report in January 1902 saying that the desert’s soil was too full of alkali for most crops. In addition, many people feared that the basin’s summertime high temperatures of 110 to 120 degrees Fahrenheit would be too much for field laborers to tolerate. While these concerns proved groundless, they did make the task of raising financing from skeptical Eastern investors much harder.
joyce pendolajoyce pendola2006_3_40
The company faced a more immediate problem, though: silt. The Colorado River slices energetically through the Rocky Mountains, eroding rock and picking up sediment until it is carrying millions of tons of minerals. Among the world’s major river systems, it is one of the most sediment-heavy. Trying to complete the project within its budget and timetable, CDC dug the floor of its headgate to a level five feet shallower than Chaffey’s engineering studies had indicated was desirable. Difficulties with ground water may have prompted this shortcut. The result was that during dry periods of the year, when the river’s flow dropped to just a few thousand cubic feet per second, water entering the canal slowed to the point where it would drop some of its sediment load. It soon became apparent that the canal was becoming clogged with silt.
The company was not prepared for how quickly the canal would silt up. Even as CDC continued recruiting settlers, its capacity to deliver water to them hit a shoal. The valley experienced a moderate shortfall in the winter of 1902–3, and in the following winter the situation became dire. Rockwood (who had bought up enough CDC stock to oust Chaffey and regain control of the company) responded by digging bypass channels to get around the silted-up section, but these quickly became clogged themselves. He also let the river’s high summer flows wash through the canal and scour out its upper segment. Unfortunately, the heavy scouring flow ended up depositing more silt than it carried off. CDC’s dredges worked flat out, but there weren’t enough of them. Angry farmers sued the company as their plantings withered.
These farmers were pioneers in the true sense, trying to make productive terrain out of a harsh and unforgiving environment with no certainty of success. As the author William deBuys wrote, “The arduous first years of valley settlement demanded constant labor, and even more by way of enduring heat, wind, sun, and privation. For most, the struggle to gain a toehold in the desert carried the taste of sand between the teeth, which the silty water of the new canal hardly washed away.” Still they came to the valley, whose population increased from 2,000 in 1902 to 7,000 in 1903 and 10,000 in 1904. Despite the pessimistic predictions of the Agriculture Department, nearly everything they planted grew in profusion, including barley, cotton, and all kinds of fruits and vegetables. Alfalfa yielded five or six crops a year.
In September 1904, facing another winter of low flows and inadequate water supplies, CDC cut a brand-new channel between the river and the Imperial Canal. This new cut, which was also meant to be temporary, was situated four miles south of the international boundary, and it had absolutely no controls on the flow of river water into the canal. Constructing proper headgates, it was assumed, could wait. This assumption proved to be Rockwood’s tragic mistake, the careless expedient that unleashed consequences beyond anyone’s imagining and ultimately beyond his own ability to cope.
Under normal circumstances, the company might have gotten away with it, but 1905 and 1906 saw record rainfalls across the West. In February 1905 the first of a series of floods surged through the lower course of the Colorado River. CDC decided that with spring coming and even higher water in the offing, it would be prudent to close the new Mexican cut and rely on the original intake. (With the season’s abundant flow, silting would not be a problem.)
Twice a dam of timber pilings, brush, and sandbags was built to seal off the Mexican cut, but each time a fresh spring flood destroyed it. By June the waters rushing through the new cut had widened it from 60 feet to around 160, and with 90,000 cubic feet per second—almost twice the previous year’s maximum summer flow—barreling down the river, more water was entering the Mexican cut than the Imperial Canal could distribute. The overflow spilled toward the lowest elevation, the Salton Sink.
The water submerged the buildings of the New Liverpool Salt Company, which had been mining salt on the lakebed since 1884. (The company’s saltworks are what gave the Salton Sea its name.) Residents obtained a federal injunction against CDC, but the court’s order was no more effective than King Canute’s command to the tide to stop flowing, since CDC had run out of money. In the summer of 1905 Rockwood surrendered effective control of the company to Edward H. Harriman’s Southern Pacific Railroad in exchange for a “loan” to CDC of $200,000 to carry out repairs.
The Southern Pacific’s immediate concern was to save its tracks in the area from inundation. (Eventually more than 60 miles would have to be rebuilt at higher elevations.) In the longer term, though, the railroad saw a business opportunity in settling the valley and bringing its produce to the world. But the railroad soon found that it would take far more than $200,000 to repair the breach. With Harriman’s blessing, the Southern Pacific forged ahead, keeping Rockwood on as assistant general manager of CDC—in essence, the chief engineer.
With his plan for a dam having failed, Rockwood tried a different approach. The Mexican cut sat opposite a small island in the middle of the river. After the summer flood abated in July, Rockwood made two unsuccessful attempts to build a jetty between the island and the west bank of the river, just above the cut. This was meant to divert the current around the island’s east side, thus taking pressure off the cut (which was now wide enough to be termed a crevasse) so that work could proceed on closing it.
The first jetty was abandoned when rising waters made it impossible to complete. The second one was still under construction at the end of November, when a fearsome deluge came down the Gila River, the Colorado’s unpredictable Arizona tributary, bringing with it huge flotillas of driftwood. The destructive force of 115,000 cubic feet per second of water, driving all the loose timber before it, ripped away the unfinished jetty as well as the northern portion of the island.
Water gushed back into the Mexican cut. Soon it was 600 feet wide and carrying 80 percent of the Colorado’s water toward the Salton Sea, which had grown to cover 150 square miles. Imperial Valley settlers were still getting their irrigation water, but by the end of 1905 the entire valley was in danger of becoming a vast lake if the Mexican cut was not closed off.
People ranging from professional engineers to cranks offered ideas for stopping the deluge. The railroad chose to work on two solutions simultaneously. In the short term, it would follow Rockwood’s plan to build yet another bypass channel, with a new, larger headgate, just north of the Mexican cut. This would keep the Imperial Valley’s water flowing while CDC tried yet again to close off the crevasse. For a long-term fix, it would install a permanent headgate of concrete and steel at Hanlon Heading, echoing Chaffey’s original plan, and remove the silt from the first four miles of the canal, using a steam dredge custom-designed for the job.
Time was of the essence. The idea was to take advantage of winter’s low flows in the Colorado to channel all its water into Rockwood’s new bypass, making it much easier to dam the Mexican cut. Crews worked around the clock from January to April 1906, completing Rockwood’s gate on April 18—coincidentally, the day the great earthquake struck San Francisco. But it was too late. By then the Colorado was already discharging 32,000 cubic feet per second through the crevasse, more than Rockwood’s gate was designed to handle. There was no point in even trying to divert the stream from the crevasse.
Once again the engineering teams had underestimated how much effort and material would be required to get the river under control. The author George Kennan put the quandary in perspective in a 1917 book: “Nobody had ever before tried to control a rush of 360,000,000 cubic feet of water per hour, down a four-hundred-foot slope of easily eroded silt, into a basin big enough to hold Long Island Sound. There was nothing in the past experience of the world that could suggest a practicable method of dealing with such conditions.”
With this failure, Rockwood stepped down (perhaps not voluntarily) in favor of the Southern Pacific’s choice for chief engineer, Henry T. Cory. Rockwood continued to claim, implausibly, that he could have contained the flood if only others had followed his recommendations. But Cory had the temperament that the Southern Pacific was looking for, with the courage of his convictions and the sober determination to see his plans through.
Work progressed on the permanent gate at Hanlon Heading, but construction was not finished until June 28, several months into a second consecutive year of unexpectedly high spring flooding. The new structure was built to the proper depth and rested on a solid rock foundation; it had 11 gate openings, each 12 feet wide and 10 feet high, which were designed to pass the entire low flow of the river. Meanwhile the crevasse continued to expand throughout the spring until the sheet of water forcing its way in, now essentially the entire flow of the Colorado River, measured a half-mile across.
In July, with the seasonal slowing of the river, Cory summoned all the means at the Southern Pacific’s disposal to dam the crevasse. Many engineers thought the idea was impractical. They believed that the fill would simply sink into the thick layer of silt at the base of the crevasse, which had almost the consistency of quicksand. Moreover, they thought that during construction, the current would dislodge rocks from the top of the structure, finding its weakest point and rushing into that gap until it was too strong to arrest. Also unclear was the question of what resources would be obtainable, especially in light of the competing emergency in San Francisco. The engineering teams were not even sure that the Southern Pacific would continue financing the operation with its prospects of success so uncertain.
Undaunted, Cory and his workers went ahead. They built a rail spur to bring freight trains directly to the crevasse. They started a quarry at Pilot Knob. From Los Angeles came wooden piles, metal cable, and heavy timbers. Teams of Indian workers wove brush mattresses of arrowweed and willow; these would help distribute the weight of the rocks (which would be dumped from a trestle over the crevasse), preventing them from burrowing into the silty channel bottom. The mattresses were bound with heavy cable, pulled across the water’s surface by barge, and released, at which point the accumulation of silt quickly sank them to the bottom. There they were anchored with pilings driven by pile drivers situated at opposite banks. Ultimately 130,000 square feet of the crevasse bed was covered, spanning the 1,300 feet from shore to shore with a brush foundation 100 feet wide.
By early August the river had receded, exposing sandbars on either side of the cut and leaving it 600 to 700 feet wide. As the mattresses were fixed with pilings, cross members were added to link the pilings and create a trestle 10 feet wide across the crevasse. A rail track was built on top of the trestle, and by mid-September the brush foundation was complete and the rickety trestle bridge was supporting its first trainloads. Three hundred railcars called “battleships,” capable of releasing their loads on either side, were obtained from the Union Pacific Railroad and put into service, dumping large rocks and clay around the clock. By this method, crews succeeded in raising the riverbed by six feet, enough to deflect most of the current through Rockwood’s bypass, where its passage could be governed by the wooden headgate.
The arrangement held up for about a month. On October 11, following a week of disturbing evidence of leakage and settling of its abutment under the pressure of current and driftwood, Rockwood’s gate succumbed. Once again the Colorado River’s water was flowing freely toward the Salton Sea, this time through a new channel that had been dug specifically to remedy such a problem.
So Cory and the workers proceeded to dam the bypass channel too. Trestles above and below the site of the destroyed Rockwood gate were repaired, and a third trestle was built a short way down the channel. Work proceeded apace on rock dams in these three locations as it continued in the crevasse, which was almost dry, since nearly all the river’s water was now flowing through the bypass channel. By October 29, after thousands of tons of rock had been dumped, the water level had been raised enough in the bypass channel that the Colorado began flowing down its old channel toward the gulf for the first time in months. A week later, on November 4, the bypass channel was closed off completely.
Once again, the Southern Pacific’s victory lasted only a month. In the first week of December a fresh surge down the Gila proved more than the Colorado’s streambed, now encumbered with sandbars and vegetation, could drain off. Cory’s rock dams held, but the river, finding the weakest point in its containment system, seeped into CDC’s substandard levees about a quarter-mile south of the crevasse and caved their banks. Three days afterward the Colorado’s fury was again pouring westward and heading for the Salton Sea, through a breach some 1,100 feet wide.
Because the river’s flow remained stubbornly high, several attempts at building a pair of trestle crossings over the new crevasse—with pile drivers positioned on each side and a third mounted on a barge secured by cables—were washed out by sudden, driftwood-laden floods. The driving of 90-foot piles in midstream while the river was discharging 45,000 cubic feet per second was hazardous work, with many more complications than had been encountered building trestles in the relative calm of the previous summer’s low flows. Extra pile drivers were kept on hand in case any machinery toppled over in the current, and boats were positioned below the break to rescue any men accidentally tossed into the torrent. The first of the two trestles was in shape to carry freight cars by January 27, 1907, and the dumping of rock began immediately.
The material requirements for closing this second break stretched frontier resources to the limit. Cory commandeered every engine and car on the Southern Pacific capable of carrying ballast, halting rail traffic to Los Angeles. Fresh supplies were brought from quarries as distant as southeastern Arizona. Over a two-week period 80,000 cubic feet of rock were unloaded into the stream, to be followed by gravel and then clay as a sealant. The workers needed to raise the river bottom 11 feet in the new crevasse to make the water head south again, and on February 10 this was finally accomplished. At long last, the rambunctious Colorado had been thrust firmly back into its old bed. In June renewed flooding brought the river’s flow to a record 116,000 cubic feet per second, but the levees and dams held.
The work was not yet over. The entire levee system, 30 miles of it, needed to be built up to protect against future floods. Over the years other dams were built, and in 1935 Boulder Dam, later renamed Hoover Dam, was put into service. With this, the Colorado was definitively tamed. In 1941 a new All-American Canal through the Algodones Dunes began delivering water westward, replacing CDC’s problem-plagued route through northern Mexico.
Meanwhile, the Imperial Valley had a huge, salty lake on its hands. In the early years after the Salton Sea’s accidental creation, few people gave much thought to its future. It was widely assumed that the water would evaporate, as had happened so many times before when the Colorado overflowed. For a while after the final closing of the breach, the sea’s level did drop, by about 40 feet. In so doing, it lost about a quarter of its 1907 surface area of roughly 500 square miles. This left its surface around 230 feet below sea level, with a maximum depth of about 50 feet and a volume of 75 million acre-feet.
But this time there was a new factor in the area’s hydrology: large-scale agriculture. By the 1930s the sea had reached a dynamic, fluctuating equilibrium that it has maintained to this day, with inflows of irrigation water from the fields of the growing Imperial Valley, plus a few minor sources, just about matching the rate of evaporation. (The agricultural runoff reaches the Salton Sea mainly through the New and Alamo Rivers.) The fertilizer in this water provides vital nutrients for plankton, which in turn provide food for the rest of the food chain, up to fish and birds.
Some grievances were never redressed. The New Liverpool Salt Company pursued its case through the courts, but by this point CDC was little more than a legal fiction. Its assets were absorbed by the newly formed Imperial Irrigation District, a community-owned water and power utility, in 1916. Way back in 1891 the federal government had granted the Torres-Martinez Band of Desert Cahuilla Indians close to 20,000 acres to augment its tiny reservation in the northern part of the basin. When the Salton Sea flooded half of this acreage, the government gave the Indians no recourse except to wait for the lake to dry up. The Torres-Martinez are still waiting.
By the early 1920s it had become evident that the Salton Sea was not simply going to disappear. Yet as the Imperial Valley blossomed into the “Winter Salad Bowl of the Nation,” the sea’s presence went largely unremarked for several decades. Seining for mullet proved profitable during World War I, and again during World War II, when ocean fishing became hazardous, and the sea’s scenery and wildlife attracted some tourists. Few people, however, had any long-term plans in mind.
In 1928 the sea was designated a drainage reservoir, a sort of pit of last resort for the backwash of human enterprise. In 1930 the federal government established the Salton Sea National Wildlife Refuge on its southern and southeastern shores, though owing to a rebound in the lake’s level since then, 90 percent of it now lies underwater. During World War II the Navy built a base on the eastern shore. The Army also used the lake for target practice, including the dropping of dummy atomic bombs. After the war the Navy base was converted to rocketry research until the water level rose again and submerged it.
If humans were slow to understand the Salton Sea’s potential, waterfowl were not. As early as 1906 a writer remarked on the large numbers of geese, ducks, and pelicans. The new body of water immediately became an important stop on the Pacific migratory flyway, attracting more than 400 species. Its status as a refuge grew more important as California was developed and 92 percent of its wetlands disappeared. Today five species that live on the sea are endangered, particularly the brown pelican and the Yuma clapper rail, which have few other Western habitats.
At first the fish that sustained these large avian populations were freshwater species that had washed down from the Colorado. That changed as agricultural runoff, up to five times as salty as Colorado River water, made up an increasing proportion of the sea. With no natural inflow of pure water and very little rainfall, the sea’s salinity kept increasing. Soon the freshwater fish species died off. From the 1930s onward the California Department of Fish and Game tried to introduce saltwater species and ones that migrate up rivers, but they died too.
In 1950 state biologists decided to empty into the Salton Sea whatever their nets in the Gulf of California happened to catch and see what survived. Three species ultimately proved hardy enough: a bait fish called the Gulf croaker, the somewhat larger sargo, and a predatory fish, the orangemouth corvina. In the 1960s three species of African tilapia were introduced and quickly became the most numerous fish in the sea. The smaller fish, the tilapia and croakers, as well as some of the wading bird species, fed off marine pileworms, which had first been placed in the sea in 1930 as part of an attempt to introduce striped bass. The bass died off, but the pileworms reproduced by the millions, feeding on algal growths and the 400 species of plankton.
After World War II, tourists and fun seekers started making more use of the sea. Boating and water-skiing were soon joined by sport fishing, as the corvina weighed up to 30 pounds and had a reputation for putting up a fight. With Palm Springs, just off to the northwest, developing into a playground for the wealthy, the Salton Sea had a brief taste of Hollywood glamour in the 1950s. An impressive list of celebrities made appearances, and even President Eisenhower tried out the new Salton City golf course. The Salton City 500 laid claim to being “power boat racing’s richest event” and was telecast on CBS (the added buoyancy from the sea’s high salt content let boats go extra fast). By the early 1960s the Salton Sea State Recreation Area was attracting more visitors annually than Yosemite National Park.
Real estate speculators beguiled these visitors with a vision of a Salton Riviera to match the world’s great beach resorts, offering people of ordinary means and more than average credulity the chance to get in on the ground floor. The Riviera, symbolized by the circular, futuristic Salton Bay Yacht Club, did have a few years in the sun. One mid-1960s writer hailed Salton City’s “intelligent master plan,” its new sewage system, and a planned expressway along the sea’s western shore.
Yet no amount of promotion and planning could overcome the area’s isolation. Salton City, unlike Palm Springs, never grew large enough to become self-sustaining, and attempts to attract industry failed. The sewage system did not work as promised, and the fishery began to decline, with the lake sometimes giving off a powerful sulfide odor. Moreover, the lake’s level was unstable. Because the Salton Sea is shallow, small fluctuations in the amount of water contributed by its feeder streams can greatly expand or shrink its surface area. In the 1970s rising water drowned the Salton Bay Yacht Club, but the bubble had burst several years earlier.
Boating on the sea is much diminished today, although races attempting to revive the spirit of the Salton City 500 still go on. Recreation preferences now tend toward off-roading. The area around the sea is largely the province of misfits, eccentrics, outlaws, and retirees looking to live someplace warm and dry on a few hundred dollars a month. Many of these gather at a self-governing trailer park east of Niland known as Slab City, after the concrete slabs that once supported the buildings and tents of the Navy’s Camp Dunlap. For Californians from more built-up areas, the sea, periodically plagued by shoals of dead birds and fish and giving off its characteristic stench of decay, has sinister associations, as epitomized in D. J. Caruso’s 2002 movie The Salton Sea , about crystal methamphetamine labs and the unsavory characters who run them.
In recent years the sea’s biological bounty has plummeted. The 1990s saw a number of mass die-offs of birds, some from identifiable scourges like botulism, avian cholera, or Newcastle disease, and others from unknown causes. The frequency of these events has increased over time, suggesting higher levels of ecological stress. The sea remained remarkably productive during these years despite the episodic fish kills. But excessive salinity now appears to have almost eliminated the corvina, and even in the absence of its chief predator, the tilapia population has shrunk by 90 percent since 2000. With the available food supply cut back drastically, far fewer birds are visiting the sea. For humans, California has issued an advisory limiting the catch of tilapia because of the buildup of selenium from area soils in its tissues (though a recent study disputes this warning). Arsenic, from soil as well as agricultural and industrial sources, is also a concern.
What should be done? Plans for rescuing the Salton Sea, which go back to the 1960s, generally fall into three categories: desalination, perhaps using local geothermal energy sources, with the resulting fresh water returned to the lake; pumping additional river water in and salt water out; and division of the sea into parts, with salt and pollutants to be concentrated in certain areas. Still other people advocate doing nothing and letting the sea die on its own. Though the first two strategies still have their proponents, they would be massively expensive, leaving division of the lake as the most likely course of action.
In 1997, prompted in part by the previous year’s attention-getting die-offs of endangered pelican species and in part by memories of learning to water-ski on the sea as a youth, Congressman Sonny Bono, representing the Palm Springs area, drafted a bill authorizing $327 million for construction and habitat restoration. His accidental death in January 1998 provided the impetus for the legislation to pass in the House of Representatives, but the act stalled in the Senate after questions were raised about spending so much on moving dirt before environmental-impact statements had even been completed. In the end, just $5 million was authorized to conduct a study assessing needs and priorities, with a further $3 million for a pilot project to create impurity-filtering wetlands in two places.
In the meantime other states in the Colorado River watershed were pressuring the federal government to make California stop withdrawing more than its fair share of water. The resulting Colorado River Quantification Settlement Agreement of 2003 changed the political calculus with respect to the Salton Sea by starkly exposing its jeopardy. The result of the agreement was that Imperial Valley farmers agreed to use less water, either by adopting more economical irrigation methods or by leaving land fallow. Either way, less water would run into the Salton Sea.
To compensate for this change, the state earmarked $300 million for Salton Sea restoration. One goal of this appropriation was to avoid the air pollution that would result from letting desert winds blow dust from a dry Salton Sea lakebed, something that in the mid-1960s was as unimaginable as the phrase “Congressman Sonny Bono.” As a cautionary tale, Los Angeles now spends millions each year to moisten the lakebed of Owens Lake, which the city has sucked dry, to prevent particulate pollution. The Salton Sea is several times larger than Owens Lake was, and its sediments contain toxic metals, pesticides, and other pollutants in addition to salt and selenium.
The Salton Sea Authority—created in 1993 as a consortium to mediate the interests of Imperial and Riverside Counties, the irrigation authorities of the Coachella and Imperial Valleys, and the Torres-Martinez tribe—favors a restoration scheme known as the North Lake Plan. This would involve building an eight-and-a-half-mile embankment across the sea’s middle, cutting it in two. The dike would maintain a higher water level in the northern half of the sea while allowing some spillover into the southern half. The New and Alamo Rivers would be rerouted northward to deliver their water to the northern half. By allowing salts to concentrate in the shallower southern half, it is expected that salinity north of the barrier would be reduced from 44 to 35 parts per thousand, the level found in oceans, allowing it to be stocked with marine fish. The southern half would become part salt marsh and part briny lake.
The plan has drawn criticism on several fronts. Residents of the Imperial Valley think it favors Riverside County, which is far wealthier, sticking the valley with the less attractive half of the sea and all the attendant environmental and health hazards. Valley farmers support a rival scheme known as the Cascade Plan. This plan, reports the San Diego Union Tribune , “would consist of concentric dikes built within the sea, forming sickle-shaped lakes dotted with tiered islands and wetlands. Water would cascade into progressively lower and saltier ponds toward the center of the sea, where there would be a large circular brine pool.” Supporters contend that this plan would work with smaller inflows, leaving more water for farming, and would avoid letting any of the lakebed dry out.
Other critics fault the North Lake Plan’s single-minded focus on salinity, neglecting other problems such as selenium, as well as fertilizer and sewage nutrients that foster algal blooms, whose decay causes oxygen deprivation. Although plan proponents intend to use the salt slurry from evaporation to coat the areas of the southern lakebed that dry up, and to use carbon filters to reduce waterborne selenium, others believe that these measures would not be enough to keep toxic dust out of the atmosphere. Imperial County already has the worst air quality and the second-highest incidence of child asthma in the state.
As was true a century ago, walling off large amounts of water will not be easy. The proposed dike would be tough to build, in large part because the silt underlying the sea is mucky and unstable, and up to 50 feet deep in some places. The Salton Sea Authority’s latest estimate for the cost of a dike that could withstand an earthquake in this seismically active zone is $450 million, half the projected $900 million cost of the restoration plan. Other estimates are much higher. If a desalination component is added, to treat farm runoff before it enters the lake, the cost jumps to at least $1.1 billion, and this figure does not include operating costs.
Yet another possibility is to let the Salton Sea become a hypersaline environment like Utah’s Great Salt Lake, which at 280 parts per thousand has no fish (except at the mouths of freshwater inflows) but plenty of bird life, thanks to brine shrimp, brine flies, and salt-tolerant microorganisms. If this is done, however, many bird species that now depend on fish populations will have nowhere else to go.
By the end of 2006 the California Department of Water Resources will finish its environmental study of the various proposals. The U.S. Bureau of Reclamation will complete a feasibility study along similar lines. Environmentalists stress that the sea’s preservation must be viewed holistically as one component of the general health of the Colorado Delta, but this consideration mixes uneasily with the arcane rules and procedures of Western and international water law and the seemingly insatiable thirst of California’s politically powerful coastal municipalities. The Colorado River Compact, now more than 80 years old, was based on unrealistically optimistic assessments of the river’s average yearly flow and will need to be revisited. When that happens, it will be hard to turn away from the consequences of removing so much fresh water from the delta system.
It is difficult, though certainly not impossible, to conceive of an engineering blunder as enormous as the one that created the Salton Sea occurring today. Public-works projects are now subject to extensive environmental review, and technological advances have given us much more powerful resources for predicting trouble spots. In the case of the Salton Sea, the initial mistake was compounded by the failure of those in charge to recognize how serious the situation was and how difficult it would be to rectify. The contemporary irony is that many who advocate various plans for saving or abandoning the lake have not come to grips with how knotty the problem of restoring its ecological balance would be.
Perhaps demographic pressures and the ever-present appetite for cheap real estate will ultimately override the faltering development history of the Salton Sea area. But the finite and uncertain supply of fresh water in an ecologically fragile and vulnerable basin leaves ample reason to be skeptical of claims that the Salton Sea—or what remains of it after its planned makeover—can be better than ever, even as the inflows that sustain it are increasingly drawn off for other purposes. In the last analysis, it seems likely that sustainability will come only through managing growth, not through the overmanaging of water resources in the service of unrestrained growth, as has been done in California for a century and a half. Otherwise the Salton Sea will face a murky, shriveled future.
