The airboat zips along channels that weave their way across miles of saw grass. The destination is a tree island in the distance jutting from the water like a desert mirage. Onboard are two groups of scientists intimately involved in an ambitious and costly plan to fix the ailing Everglades.
The hosts for the outing are hydrologists and research scientists for Everglades National Park. They have spent years collecting data on this United Nations-designated world treasure, one of the jewels of the U.S. park system. Mostly they have recorded decline where life once thrived. Now for the first time they may have within their grasp an opportunity to reverse the downward trend. But to succeed they need the help of the men they are ferrying through this landscape of slow-moving water and expansive sky.
The passengers are from the South Florida Water Management District based in West Palm Beach. They pass their days staring at computers, crunching numbers, thinking about the Everglades, but seldom actually seeing it. They are modelers, scientists who design simulations of how the Everglades functions. Their crowning achievement is called the Natural System Model (NSM). Some hope the NSM will help save the Everglades, and it has become one of the most important aspects of a controversial restoration plan projected to cost about eight billion dollars.
As they glide over the water on this day in mid-March, the scientists from the national park point out an endangered wood stork circling above. They show how slight changes in topography influence ecological diversity and the way the water flows. A tree island that began hundreds of years ago as a subtle bump of peat on a limestone bed looms before them. They stop the airboat at a half-submerged stubby clump of bay and dahoon holly trees. The boat can go no further.
To experience the tree island, the modelers must get wet.
Slogging through the mud, brambles, and insects brings them to a level of Everglades detail they rarely experience. Their usual perspective is of a roughly 10,000 square-mile watershed and how it acts over decades. The modeling they do is part of an intensive multimillion-dollar research effort under way to comprehend the Everglades.
The motivation is simple. All agree the Everglades is in peril. All agree more research is needed to understand how the system worked at its optimum, how it has changed, and how much can be salvaged. But few concur on just how to restore it and in what order to satisfy the diverse needs of the watershed, including the human ones. As development encroaches and deadlines near, time is running out for the ecosystem and the planners rushing to save it.
One problem is vision: There is little consensus about what a restored Everglades should or could be. More than 50 percent of the original Everglades that stretched from Lake Okeechobee to the Florida Bay is already lost forever. More has disappeared at the top of the watershed than at the bottom. How should the remaining pieces, sectioned off by canals and levees, fit back together? How much additional land is needed and what will be the ecological benefits of its acquisition? Everyone has a position but no one knows for sure.
On July 1 Congress will receive the Central and Southern Florida Project Comprehensive Review Study, crafted by a multiagency task force for Everglades restoration, even though scientists don't have all the information they need to complete the plan. The irony is that it was national environmental groups that lobbied for the July deadline in 1996 legislation. (Some suspect the haste might have been an effort to help presidential candidate Al Gore.) The answer to the time-and-data dilemma resulted in a "conceptual" plan with more goals than details on how to arrive at solutions. The deliberate vagueness has led to an ongoing battle among different groups to wrest more from the plan for their own needs. Environmentalists fear that in any contest where the interests of the ecosystem are pitted against those of development, nature will lose.
A controversial aspect of the plan centers on what to do with three sections of the Everglades called the Water Conservation Areas, which form the northwest end of Miami-Dade County and much of western Broward. The conservation areas are run by state authorities and do not have as strict environmental protection as the national park to the south. They are particularly prized by hunters and recreational users, many of whom camp on the tree islands. These users have complained that Everglades restoration is geared more toward protecting the national park and supporting a growing urban population, both at the expense of the conservation areas. They claim part of the problem is that policymakers are not interpreting the NSM correctly.
Responding to the loosely defined plan, the federal Government Accounting Office issued a scathing report this past April. "A strategic plan that clearly lays out how the initiative will be accomplished and includes quantifiable goals and performance measures has not yet been developed," the GAO report revealed.
Thrust into the middle of the muddle are the modelers. As decision-makers cast about for a benchmark to determine what constitutes Everglades restoration, many have embraced the Natural System Model.
The NSM is a computer simulation of how water flowed in South Florida before man intruded. In a system as vast as the Everglades, where a change in one place can have dramatic repercussions elsewhere, the only way to understand the impact of proposed engineering projects is by using such models. The NSM tries to answer three central questions about the Everglades as it was 100 years ago: How much water flowed? What was its path? How deep was the water in different parts of the system at certain times of the year? Policymakers presenting the plan to Congress hope that returning the water to century-old patterns will restore the ecosystem of that time as well.
But the modelers fear their creation is being misused to compensate for a lack of information and to dodge hard truths about what needs to be done. Some scientists, environmentalists, and hunters believe the current plan pays more attention to water levels than to the way the water should flow. They believe the flow of water at specific times of the year is the key to a thriving wildlife population. They argue that policymakers are really concerned about water supply and development, and not actually about restoring the Everglades.
"They are not thinking of it as an ecosystem," complains Jack Moller, a board member of the sportsmen's group the Florida Wildlife Federation. "It is all highly speculative." Moller thinks planners have not allowed sufficient land for water storage at the top of the remaining Everglades.
Even the model's original inventor is troubled.
"The Natural System Model was designed as a compass, not a blueprint," insists Tom MacVicar, who largely created the first version of the NSM while a senior engineer with the water management district in 1988.
The glowing computer screen pulsates red and blue. The colors expand and contract as they wash over identical maps of South Florida that flank either side of the monitor. In the middle a display steadily ticks through the months of each year beginning in 1965 up to 1995, and then over again in an endless loop. A pause at any given date freezes the ebbs and flows of this bizarre form of time-lapse imaging.
The colors on the two maps identify water (and its depths) as it flows from Lake Okeechobee south to the Florida Bay. The map on the left is version 4.5 of the Natural System Model. It shows how water would move in South Florida with the topography and vegetation of a hundred years ago -- in other words, with no human impact -- but using the rainfall patterns of the past 30 years. (Modelers can't estimate what rainfall amounts and frequencies were, consistently, throughout the system a century ago.)
On the right side of the screen, the map shows South Florida as it stands today, cities, canals, and levees included. This is the model of the current managed system. The South Florida Water Management District uses this modern-day tool of hydrologists to determine how water gets distributed throughout South Florida.
In both systems different volumes of water move through the Everglades depending on whether it is the wet or dry season. The water's movement in the model makes the system appear to breathe. But the real Everglades does not move as quickly as the pulsations on the screen. And before canals hurried water out to sea, the flow of what Marjory Stoneman Douglas called the "river of grass" was so slow and languid through the saw grass prairies as to be almost imperceptible.
The elevation of Lake Okeechobee at the top of the Everglades was about twenty feet above sea level. On its 100-mile journey down to the tip of the peninsula, the land sloped, on average, only about two inches per mile. (Imagine a long pane of glass tilted slightly with a thin sheet of water flowing down it.) During each wet season, rainfall increases water levels. The Natural System Model shows that in the untouched Everglades, water from one wet season reached Florida Bay just as the next year's wet season was beginning. The result was constant water movement, and in most years, constant water coverage. Today the water is largely funneled or trapped, and not allowed to flow in one uninterrupted sheet as it once did. The Everglades is now frequently drier in the dry season and wetter in the wet season.
The two representations of the river of grass are running on the desk of Jayantha Obeysekera, the water management district's chief modeler. Obeysekera oversees a staff of roughly 25 hydrologists, mathematicians, and engineers. The computer is one of two in his corner office in the warrenlike maze of rooms and cubicles in West Palm Beach. On the wall in back of his desk is a quotation from Albert Einstein: "Equations are more important to me, because politics is for the present, but an equation is something for eternity."
The Natural System Model is unique, and Obeysekera and his crew are on the frontiers of the science of computer modeling. Most models are designed to show decision-makers how the future might appear, not resurrect the past.
"[The NSM] is very unprecedented," says Obeysekera. "We have never developed a model that tries to mimic what happened 100 years ago."
Modeling has come a long way in the century man has tried to engineer the Everglades. Hydrologists in the district's early years, before the advent of computers, used an analog model. It worked under the premise that electrical current could simulate the flow of Everglades water. They designed a giant circuit board to mimic the watershed: Resisters were supposed to behave like vegetation and delay the water, while capacitors served to store water, in the same way that current conservation areas do. Back then, to simulate the change in a canal, electrical engineers had to walk around circuitry mockups. Obeysekera says the U.S. Army Corps of Engineers even had huge adding machines that were hand-pulled to execute the massive calculations involved.
Today computer programmers and mathematicians input data in the form of algorithms, which are the basis for trillions of computer equations that make the Natural System Model move.
The 46-year-old Obeysekera arrived in the United States in 1978 from Sri Lanka. His work experience in the populous Third World island off the Indian subcontinent gives him a unique perspective on Everglades restoration. In his native land most rivers are diverted for irrigation. Flooding is common. There is little emphasis on environmental issues, and pollution is widespread. There are more problems in Sri Lanka than in Florida, he says. (Indeed many ecologists surveying the world's myriad environmental troubles believe that if a rich, technologically advanced nation such as the United States cannot restore the Everglades, the prospects for fixing similar problems throughout the world are grim.)
Obeysekera was teaching hydrology at Colorado State University when a colleague enlisted him to work on restoring Florida's Kissimmee River. The corps had straightened the meandering waterway in 1961 with ecologically disastrous results. (On June 5 the corps broke ground on a project to restore the river.) Even as a professor of hydrology, Obeysekera was not prepared for the complexity of the Everglades.
"We had textbooks and the normal hydrology that you teach and I come down here and I realize none of this hydrology is in textbooks," he still marvels.
Although the Everglades appears flat, it is in fact riddled with slight differences in elevation. Much of the original watershed was a vast system of interlaying ridges and channels called sloughs (rhymes with twos) through which water flowed. The changes in ground topography gently nudge water in certain directions and account for the diversity of plant and animal life. When the water level drops in the dry season, it concentrates in the sloughs. The shrunken pools of water increase the density of fish. Wading birds flock to these pools of water for an easy feast. Over millenniums the cycle of life evolved to follow the movement of water.
Some scientists believe the ridge and slough system is vital for the health of the Everglades. But these subtle changes in topography are a level of detail too small for the NSM to show. Perhaps the best-known example of this system is Shark River Slough, whose main path cuts through the northern end of Everglades National Park. Within this enormous slough are dozens of miniridges and sloughs. In the 1800s the closely held secret to Seminole and Miccosukee navigation was their knowledge of the ridge and slough system. Where whites saw impenetrable saw grass, the Indians knew how to follow the natural channels, the key to getting around the maze. Today the airboater who does not know ridges and sloughs may end up waist-deep in muck pushing his boat off a rise.
In order to model the flow of water, scientists must take into account the topography and the vegetation. In addition the southern third of the Everglades sits on porous limestone that covers a huge aquifer of water and acts like a giant sponge. The rate by which water disappears through movement, evaporation, and absorption must all be factored into the model.
Obeysekera admits the NSM is so new and complicated the modelers are unable to test for accuracy. "We are trying to find ways of doing uncertainty analysis for NSM correctly," he says.
The problem is too many variables. The NSM covers 9312 square miles broken into 2328 two-mile-by-two-mile computational cells. Each cell is interconnected to its neighbors in different ways. "You have to change the system many, many times to do an uncertainty analysis because to change one point in the system is to change everything," he explains.
Scientists hope to add data to the Natural System Model in an attempt to craft a more precise tool for policymakers.
One area that will make the NSM more reliable is soil analysis. For the past three years Christopher McVoy, a district ecologist, has sifted the layers of the Everglades earth in an enormous detective job. Through his research he reveals the alterations in soil before and after engineering met the natural system.
"The changes to the ecology of the area began almost immediately with drainage [in the late 1800s]," McVoy says.
Because ecologists know how some key vegetation thrives at various water levels, by looking at soil evidence dating back 100 years they can try to deduce how much water was once there. The implications are potentially enormous.
In many areas the shortage of water exposed formerly wet soils, which then dried and oxidized priceless topsoil. Ridges that jutted above the water dropped. Sloughs filled with peat and closed. Tree islands sank. Now, if the water sent back into the Everglades is too deep, wading birds cannot fish and the roots of tree islands will rot. In other parts of the system, such as in Everglades National Park, water levels probably have changed little. So in a physically reduced and altered Everglades, historic water levels as predicted by the NSM might be appropriate for some sections but not others.
Besides excavating in the soil, McVoy and the modelers have also searched through the records of historical and scientific accounts of the Everglades to glean information about the past. In one account from the 1898 book Across the Everglades, the naturalist and adventurer Hugh Willoughby describes his journey from the Miami River through what is now the national park.
"The stream here loses itself among the lily-pads," Willoughby wrote at one point in his trip. "Before you lies a sea of apparently pathless grass, cutting in all directions, spreading out like the lines in the human hand, and whichever one you take you regret that you did not choose the other."
Since the late 1800s development and agriculture have forced a steady drying, replumbing, and asphalting of South Florida. Changes began with a series of canals to drain Lake Okeechobee, which historically overflowed into a vast plain of saw grass below the lake bed. (Today that area is largely sugar cane.) Then in 1910 the State of Florida dug four major canals that caused the most serious damage: the New River, the Hillsboro, the Miami, and the West Palm Beach. The canals, all originating in Lake Okeechobee, funneled water directly to the sea. By the 1940s the Everglades became so dry that huge fires broke out, which, through exposure and erosion, helped flatten the system of ridges and sloughs considerably.
In 1947 a mammoth flood left 90 percent of southeastern Florida underwater. A year later the Army Corps of Engineers responded by providing better flood protection and modifying the four canals, channeling more water back to the Everglades. The engineers called it the Central and Southern Florida Project. A state agency that later became the South Florida Water Management District was created to operate the corps' creation. To reflood the peat soils and the Everglades marshes, they built conservation areas to store water, essentially creating a series of bathtubs. While the conservation areas improved water levels in the previously overdrained Everglades, they did so at the expense of water flow.
With the new flood protection, the corps ushered in 50 years of continuous economic growth. The project became a de facto land-use plan: What could be kept dry could be developed. For a 5000-year-old ecosystem, the results were catastrophic. Further expansion and development, or what the bureaucrats like to call "the built environment," threatens the very quality of life in South Florida. The plan Congress received is widely known as the Restudy because it entails rethinking the original corps project.
Congress and the State of Florida will be asked to allocate about $400 million as the first year's installment, in an effort estimated to cost $7.8 billion over roughly 35 years. (This is about twice what it cost to bomb Yugoslavia.) The Restudy expense would be split between the state and federal governments. The plan ambitiously promises to revitalize the Everglades so that birds and animals can return, as well as to ensure sufficient water supply for a burgeoning urban population.
Every year millions of tourists and Floridians visit the surviving natural wonders: the water conservation areas, the national parks, wildlife refuges, and the marine sanctuary that encompasses much of the coral reefs. All of these areas are in varying degrees of jeopardy. The coral is succumbing to disease. The sea grass in Florida Bay is dying, and is being replaced by toxic algae blooms. The vast rookeries of wading birds that made the Everglades famous are gone. The number of wading birds has dropped to ten percent of what it was just 50 years ago. Examples of deformed fish have been found in at least ten species. Mercury contamination is so extensive that authorities recommend avoiding eating large-mouth bass and other fish caught in roughly one million acres of the Everglades. The tree islands, their roots rotted, are falling over while still alive. Deer starve on little patches of land or drown in rising water. If the natural Everglades continues its decline, the visitors who sustain much of the local economy will eventually go as well.
The destruction of the watershed has repercussions beyond the loss of wildlife or tourist dollars. If the decline is left unchecked, its implications will be felt by every resident of South Florida regardless of whether they are an outdoor enthusiast. Fresh water will likely drop in quality and supply while increasing in cost. Much of the wetlands, which once captured the water and purified it, as well as provided an important habitat for animals, has become subdivisions and strip malls. Ten million people are expected to move to South Florida in the next 50 years. As greater demands are made on a vastly reduced system, the Everglades will become increasingly unable to perform its vital functions. Years of droughts and floods will increase. Wildlife will continue to disappear.
Jayantha Obeysekera is showing the model of the current system at work. As the model runs on his computer, he maintains an ongoing commentary as the years flash by: '69 was a wet year, '71 is drying out, '89 was a very dry year, the '90s are wetter. The water sent through the system tends to pond in the conservation areas rather than flow, he says.
"You can see the stacking of water behind levees and the drying out of certain areas in the northeast Shark Slough," he says pointing to the gradients of color on the right-hand side of the screen that shows the managed system.
Environmentalists believe the answer to this ecologically devastating process is not just to return the area to historic water levels, but to open up the system and let it flow. They fear the current plan is really about continued water supply for urban development and agriculture.
"Are we paying for restoration? That is the key question," asks John Marshall, an environmental activist and nephew of the celebrated South Florida ecologist Arthur Marshall. "More water [alone] will kill more habitat. When it rained, it flowed. Now when it rains, it drains or is compounded."
It is late May in the Embassy Suites hotel in Boca Raton. Marshall has come for an Everglades restoration science forum. (In early June the forum, which was designed to bring policymakers and scientists closer together, made headlines. One of the organizers, a scientist, was fired in part for badmouthing policymakers there.)
Marshall has taken a room on the hotel's third floor and is holding court with other environmentalists. On this day they are talking intensely with the GAO federal auditors. As the two GAO officials slip out of the room, Marshall begs them to keep probing the Restudy effort.
He does not believe the plan will find easy acceptance in Congress.
"It is going to be a fur ball for about six months," he says.
Currently Marshall and other environmentalists are screaming foul. They say policymakers directing the U.S. Army Corps of Engineers have sold them out: The planners have ducked allocating enough land to ensure habitat for animals and space for water movement, and instead have offered untested technology to store water in expensive deep-injection wells. The motivation, these environmentalists say, is to ensure water supply for urban growth, not for the environment.
Jack Moller, a hunter and activist, is less worried about the technology as long as storage is provided. If it's not, then the 52-year-old sportsman fears that under NSM-predicted water levels, the water-conservation areas where he has roamed for 45 years will continue to die from flooding.
Moller first started exploring the Glades as a six-year-old boy with his father. When they wanted to get into the Everglades, they parked their car at the Opa-locka city hall, which was in those days on the edge of the system.
This past January Moller retired as an administrator for the Miami-Dade County school system. These days he devotes much of his time to Everglades restoration. "I suppose I am stupid and stubborn," he says self-deprecatingly of his often successful efforts to question scientists and direct politicians.
Moller and his wife have a hunting cabin in Big Cypress National Preserve, where they spend about 100 days a year. Moller is clear-eyed in his view of the future of South Florida. It will be impossible to stop people from coming. The only way to protect the land for the environment is to buy it for the public. Casting a skeptical eye at many of the national environmental groups, he suggests only half-jokingly that the best thing they can do for the ecosystem is buy two houses and then leave. He has seen enough governmental bungling to be somewhat distrustful of the stock answer to how problems in the Restudy will be resolved. According to the plan, scientists will make changes to the Restudy as more accurate information is gathered, through what they call "adaptive management." Moller asks the obvious question: "Adaptive management for what system: the urban or the natural?"
If Moller is leery of the idea of adaptive management, it is unlikely Congress will greet it with any more enthusiasm.
"I know for a fact that Congress doesn't like to hear the words 'adaptive management,'" says Dan Cary, who heads up the water management district's Everglades restoration planning department where the modelers work. "It makes them uncomfortable because it sounds like we are going to spend a lot of money and we might be wrong and they don't want to hear about it," he comments.
Cary says that though it might be alarming to outsiders, adaptive management is simply the scientific method where hypotheses are challenged until proven. "I don't worry about it too much because it is healthy," he insists. "In fact you have to have it to improve the model."
Certainly in the case of the NSM, science continues to evolve. Jayantha Obeysekera promises that McVoy's detailed soil research will be incorporated into a new version of the model fairly soon.
The modelers are sitting in Obeysekera's office at the South Florida Water Management District, looking at the maps of the Everglades running on the computer screen. What appears simple and logical is in fact dependent on countless variables and instantaneous mathematical decisions. The technology is astounding but ultimately cannot take the place of hard policy decisions, the modelers say.
"One of the [problems] is that when you look at a graphic like that, it's too damn good in a way," muses Dan Cary. "They did too good a job graphically and there is a little bit of an illusion that we have some magical knowledge that is very precise about how this system works, when in fact the reasons these models were developed was to get broad-brush ideas. We have to remind ourselves that we are missing a lot of important stuff."
As those who would restore the Everglades stumble along on their path, the world is watching. Obeysekera says tour groups of scientists from Japan and Europe often visit to learn about the efforts of the modelers. They hope to take home with them lessons on how to restore their own flagging ecosystems.
"Basically we have screwed up the world all over the place and we are finding out that it is a lot harder to put things back together than it was to take them apart," Cary continues. "I honestly believe there is a solution that everyone can live with.
