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Rising Water: Restoring Ruined Wetlands
by Brendan Borrell
Less than a month after Saddam Hussein's regime fell in April 2003, the first trickle of water seeped back into the soil of a former marsh near Basrah in southern Iraq. The draining of this marsh and a massive network of connected wetlands, masterminded by Hussein in 1993 to quell and punish a rebellion by his Shiite opponents in the south, was both a cultural and a biological tragedy.
|Marsh Arabs, or Ma'dan, and their ancestors depended on Iraq marshes for millennia. Their way of life was devastated when Saddam Hussein's regime drained the marshes. (U.S. Army Corps of Engineers)|
Satellite images from 2000 revealed grayish-brown patches where the marshes once were: dead reeds, desert shrubs, and dry ground. A region that once was an oasis for millions of birds was now desert. A mere 12 percent of the original marshes remained.
Unfortunately, these marshes are but one example of the accelerating decline of wetlands worldwide. For centuries, fresh and saltwater wetlands have been drained for agriculture and industry or converted for human settlements, but the pace has quickened in the last 50 years due to growing coastal sprawl. Engineers long believed wetlands were a waste of water and breeding places for disease-carrying mosquitoes and other pests, and with the encouragement of government officials they diverted water, filled in bogs, and laid down pavement to stimulate economic development.
Yet wetlands provide invaluable benefits to people and wildlife. They form transitional zones between terrestrial and aquatic ecosystems, providing indispensable habitat for much of the world's biodiversity. They help control floods by buffering flood basins from heavy rainfall, letting water percolate out of soils gradually. They filter out contaminants from agricultural and municipal runoff before it drains into rivers, lakes, and aquifers. They provide crucial stopover points for wide-ranging migratory birds, and almost one-third of the world's endangered plants and animals depend in some way on their existence. And estuarine areas, where rivers meet the sea, serve as nurseries for coastal fisheries, which supply as much as of two-thirds of worldwide harvests.
In 1996, the Organization for Economic Co-operation and Development (OECD) published estimates that more than half of the wetlands in the United States and Europe were destroyed or polluted between 1900 and 1985. Wayne Henley of the Massachusetts Audubon Society suggested in 1965 that with the pace of coastal wetlands destruction, New Englanders should consider making clam chowder out of tomatoes. In Asia, huge swaths of wetlands have been converted into rice monocultures. The OECD also reported that, taking into account undeveloped regions in Africa and South America, an estimated 26 percent of wetlands had been lost worldwide between 1900 and 1985. That number is likely to rise in the near future. There are plans, for instance, to dredge the Paraguay and Paraná rivers to facilitate shipping among five South American countries, a project that would devastate Brazil's Pantanal, the world's largest wetland.While there is much debate about the degree to which lost wetlands can be restored, few would disagree with the need to recover—to the extent possible—many of the wetlands that have been lost over the last century. In Iraq, local communities are working with scientists and conservationists to restore the marshes destroyed by Hussein. Their efforts are mirrored in restoration projects around the world, from the wetlands bordering the remnant Aral Sea in Kazakstan and Uzbekistan to the flood plains of the Illinois River and the coastal marshes around the Chesapeake Bay. Whether the destruction of these wetlands was precipitated by political events or agricultural demands, we are finally recognizing that wetlands provide economic and cultural value to our landscapes.
Azzam Alwash, an Iraqi-born engineer who has led restoration efforts in the region, grew up on the marshes in the 1960s. He remembers laying his head on the edge of his father's boat and staring at the giant reeds extending toward the sky. "I saw skies full of birds," he says. He recalls seeing the dark shapes of huge fish in the water—a rich community ranging from algae-eating bunni (Barbus sharpeyi) to predatory catfish (Silurus triostegus). "I fell in love with the marshes at the time," he says.
But Hussein, who took power in 1979, viewed the marshes as a thorn in his side. During the Iran-Iraq War in the 1980s, deserters from his army sought refuge in the marshes, and the region later became a hiding place for Shiite refugees and rebel fighters.
In 1991, southern Iraqis threatened to rise up against Hussein. In response, he ordered construction of the "Third River," a canal that would divert water around the marshes. His regime's official explanation for the project was to irrigate half a million square miles of fields—an idea originated by British engineers in the 1950s. The 1990 completion of the Ataturk Dam, which Turkey built upstream on the Euphrates for both irrigation and hydroelectric power, had indeed significantly limited water flowing into Iraq's interior. But experts said that the Third River and its accompanying diversions went beyond irrigation needs and were specifically intended to eliminate the marshes.
As the marshes dried, an estimated 70,000 Ma'dan, or Marsh Arabs—a people who fished, raised water buffalo (Bubalus bubalis), wove reed mats, and cultivated rice and barley on the marshes as their Babylonian and Sumerian ancestors had 5,000 years ago—were forced to flee to Iran. Fisheries that once provided the bulk of Iraq's annual catch collapsed. The Basrah reed warbler (Acrocephalus griseldis), which breeds exclusively in the marshes, was brought to the cusp of species-wide extinction, while populations of the marbled teal (Marmaronetta angustirostris) and other bird species considered vulnerable by the World Conservation Union (IUCN) were nearly wiped out locally.
Alwash and his wife, Suzie, were living in California when they heard about the devastation. They were shocked. In 2000, they began drawing up plans for a nonprofit organization called Eden Again, which would supply Iraqi organizations with scientific support for restoration efforts. At that time, U.S. government scientists thought it was too late for restoration: The Ataturk Dam was already diverting too much water from the Euphrates, and the former marshes were blanketed in a layer of salt that prevented plants from taking up water and nutrients. The marshes were also strewn with leftover ordnance, land mines, and other battlefield debris from the Iran-Iraq War.
|The goliath heron (Ardea goliath) is among the birds that breed on the Iraq marshes. (photos.com)|
The Alwashes were not deterred. It was nearly impossible to get accurate information on the state of the marshes, but the couple spent weeks in libraries searching for data on water flows and the design of Hussein's canals. Alwash consulted extensively with his father, a former irrigation engineer who had been living in Washington, D.C., since the first Gulf War. They set up their own blue-ribbon panel of eminent wetlands scientists who were more optimistic about recovery, but were concerned that the marshes were contaminated by heavy metals and pesticides from agricultural and industrial runoff. In addition, small villages and farms that had sprung up on the edge of drained marshes would be destroyed if the marshes reflooded. Chief scientist Curtis Richardson from Duke University in Durham, North Carolina, said at the time, "If we can restore one-third of the marshlands, I would consider it a miraculous recovery." The panel recommended a three-month monitoring period to test for chemical pollution.
But that monitoring period never happened. Instead, shortly after the fall of Hussein, residents and returning Ma'dan quickly razed the extensive dikes and dams blocking the flow of water. Richardson joined Alwash on the first team to visit the marshes after the initial 2003 flooding. The group was first led by U.S. military experts and later by local Kurdish guards. It was a dangerous endeavor, but the political sentiment among Iraqis was still one of optimism. When Richardson arrived, he saw that parts of the marsh had been so badly burned by Hussein's forces that the sandy soils had turned to glass. Local people came up to the convoy and begged for water.
Seeing this, Richardson remained skeptical about the prospects for the reflooded marshes. But then, he says, "We got to those lakes and to our surprise there were two feet of clam shells,"—the marshes were coming back to life. By February 2004, nearly 20 percent of the former marshes were reflooded, and vegetation cover was expanding at a rate of 300 square miles a year.
Richardson's analysis, which was published in the journal Science in 2005, alleviated the scientists' major concerns. Pesticides and other toxins were not detected in four marshes they sampled, and they found the water was well-oxygenated—meaning it wasn't getting choked with algal growth. As expected, there were high levels of salt in the soils and salt-tolerant plants such as saltbush (Atriplex sp.) and the Athel tree (Tamarix aphylla) were thriving throughout the region. High levels of sulfates—a naturally occurring mineral in brackish water—were only discovered in the eastern portion of one marsh, possibly inhibiting the establishment of vegetation in that area.
Omar Fadil is a Baghdad-based ornithologist with the nonprofit organization Nature Iraq, which has been working with Eden Again to restore the marshes. Fadil says he has seen plenty of cormorants and ibises, and in the last year witnessed the return of the imperial eagle (Aquila heliaca), a migrant. Ornithologists also report the return of the Iraq babbler (Turdiodes altirostris), a species not seen in the area in decades. Members of the restoration teams have reported wild boars and are keen to discover whether the rare Maxwell's, or smooth-coated, otter (Lutrogale perspicillata) has survived.
Although the marshes seemed to be thriving on the surface, the situation was more complex underwater. A healthy ecosystem resembles a pyramid with small numbers of predators at the top supported by large numbers of herbivores. But the team's surveys revealed that the aquatic ecosystem was out of whack, because of the lack of aquatic plants and invertebrates to support the herbivorous bunni, which historically was the fish with the greatest commercial value. Instead, the marshes were dominated by the piscivorous catfish, which is not eaten by the Ma'dan because of religious reasons. This lack of food resources has prevented the Ma'dan from resettling much of the marsh's interior.
The biggest hurdle now is finding a way to recreate the hydropulse, a seasonal flooding of the marshes caused by snowmelt flowing down from the mountains of Kurdistan. Extensive networks of dams in both Iraq and Turkey now block this hydropulse, which once renewed the marshes by increasing the water level, pushing brackish water out, and bringing in silt and clay. It coincided with fish spawning and bird migrations and a flush of new growth by the reeds. By September 2007, the marshes were about 68 percent flooded, but because there is less overall water in the system, Alwash and his engineers are realizing they will need to bring the hydropulse back mechanically, properly timing the release of water from dams. "It's like a symphony, really," he says. "If we don't return the hydropulse, I am not saying the marshes will die, but there will be a different system that will evolve."
With the continuing war in Iraq, it is becoming harder and harder to keep tabs on the marshes. Alwash says he has a team going out once a month, but kidnappings throughout the country rose soon after the first surveys. In 2004, five students from the University of Basrah were kidnapped while birdwatching on the marshes, although they were eventually released unharmed. "I was hoping I could take my wife and kids to the marshes, but southern Iraq is not very safe at this point," Alwash says. "Who knows? Maybe in two, three, four years things will settle down, and I can take my kids and show them the marshes, and maybe they'll fall in love like I did."
Kazakstan and Uzbekistan: A Vanishing Sea
The Ma'dan were unable to combat the government-mandated destruction of the Iraq marshes in the 1990s. Thirty years earlier and thousands of miles north of Iraq, a similar cataclysm began when the long arm of Soviet Moscow turned the spigot off on the Aral Sea in Central Asia.
Twenty miles of sand now lie between the port town of Aralsk in Kazakstan and the northernmost reaches of the Aral Sea, once a vast saltwater lake that has shrunk to half its former size. Aralsk is filled with remnants of a former era: vacant docks and fish processing plants left behind as the Aral's waters receded. A small museum highlights the region's once-rich cultural and biological heritage. Inside, a ghostly looking shovelnose sturgeon (Pseudoscaphirhynchus fedtschenkoi) is on display in a test tube. This evolutionary relict used to occasionally venture down the Syr Darya river into the waters of the Aral Sea, but it may now be extinct, according to sturgeon expert Phaedra Doukakis of the Pew Institute for Ocean Science in Miami, Florida.
In the 1950s, Aralsk and other ports along the sea processed 50,000 tons of fish a year, but the catch has declined drastically since then. By the early 1990s, the Aral Sea was biologically dead. Experts predicted that it would dry up completely by 2020.
|Aerial images show the shrinking Aral Sea in 1989 (left) and 2007 (right). (NASA)|
The decline of the Aral Sea began in the 1960s when Moscow embarked on a plan to irrigate millions of acres of cotton in the desert of Kazakstan, Uzbekistan, and Turkmenistan, which at the time were part of the Soviet Union but are now independent countries. The Soviet government diverted water from the two rivers that flowed into the Aral—the Syr Darya in the north and the Amu Darya in the south. By the early 1980s, the irrigated land was producing nine million tons of cotton a year, making Central Asia the world's fourth-largest producer of cotton. As a result, the level of the sea dropped and the water became increasingly saline. In 1988, the lake split into a northern basin and a much larger southern basin.
For a while, local fisherman tried to preserve their way of life, but sturgeon and other native fish were no longer able to survive in the salty waters. Dust storms whipped up salty sediment and pesticides from the exposed seabed, and local people told of walls of sand blowing through their towns. People in these areas have since been racked with respiratory diseases such as tuberculosis, while rates of cancer and other diseases have skyrocketed.
Biodiversity suffered as well. Along both river deltas, forest communities called tugai were once dominated by flood-tolerant Euphratica poplar trees (Populus euphratica), but a century of agricultural development coupled with the dire water situation wiped out almost 90 percent of them. The region once boasted 576 species of plants, but 54 are now nearing extinction. The reed thickets in the Amu Darya delta also vanished. By the 1990s, the endangered Bukhara deer (Cervus elaphus bactrianus), a resident of both river valleys, numbered less than 400. Other mammals, such as the jungle cat (Felis chaus)—possibly the only cat that barks—were faced with a rapidly shrinking habitat. Of the 70 mammal species and 319 bird species once recorded from the Aral Sea, experts estimate that less than half remain today.
After the fall of the Soviet Union, local people in the north were free to take matters into their own hands, but with reduced water flows, they realized they could only save a portion of the sea. In 1992, they built a dam along an eight-mile channel that separates the northern sea from the much larger southern basin, which is shared with Uzbekistan. The project would keep water levels high in the northern Aral, but inevitably desiccate the southern basin, which most scientists felt was already doomed. Joop Stoutjesdijk, a water expert at the World Bank, says it was the only realistic option. "The southern sea is just too large, and there's not enough water coming into the sea from the Amu Darya," he says. "Even if you stopped all irrigation in Uzbekistan and Turkmenistan, it would still take 50 years to come back." Unfortunately for the people in the north, their first barrier was too steep and soon eroded away. They immediately went to work on a second dam, but it failed during a storm in 1996.
Meanwhile, the World Bank had begun a series of preliminary studies related to water issues in Central Asia, with a particular interest in reviving the sea. In the 1990s, very little information was available locally for designing restoration efforts, because these areas had been so tightly controlled by Moscow. By 2003, however, the World Bank and the Kazak government were convinced that an Aral Sea restoration project could work and invested $86 million to build a more permanent barrier to water flowing into the southern basin. Stoutjesdijk says that in order to prevent erosion, they designed this dam with a shallow slope that climbed a single vertical foot for every 50 horizontal feet. The influx of funding was also used to remove bottlenecks that were reducing flow along the rivers leading into the basin.
The World Bank originally estimated it would take two years for the water to rise to the top of the dam after it was completed in 2005, but water was pouring over the spillway in just 18 months. In the last two years, 11 species of freshwater fish have already returned to the lakes from river sources, and last year's catch was much larger than that of 2004. The water level has risen more than ten feet, and the area of the lake expanded by 50 percent. Last June, Stoutjesdijk brought his swimsuit. "We came prepared," he says.
|Rusted boats rest on the dry lakebed of what was once the Aral Sea. (Joop Stoutjesdijk)|
Efforts to restore wetlands in the deltas of both the Amu Darya and Syr Darya rivers and on the dry lakebed itself are just beginning. Stoutjesdijk says that World Bank projects have helped recover an important forest and wetland around Uzbekistan's Lake Sudoche, one of the largest in the Amu Darya delta. "In Uzbekistan, we hope to look at a much smaller scale," he says. "Look at areas closer to the axis of the sea, to see whether there are important wetlands." The Syr Darya river, by contrast, is still a very wet region with wetlands stretching some 30 miles from the mouth of the river. How much terrestrial wildlife will return to the region is unknown, but the World Wildlife Fund has already reintroduced captive-bred Bukhara deer into nature reserves in Uzbekistan and Kazakstan. The sea's water quality and the health of its fishery will ultimately depend on the health of the Syr Darya delta.
This is an exciting time for Nikolai Aladin, a zoologist at the Russian Academy of Sciences in St. Petersburg who boarded a train in September 2007 with a couple of plankton nets and a trunk full of scientific equipment. Although the Aral Sea is a relatively young water body and therefore never possessed a particularly unique fauna, it was replete with a microscopic menagerie including copepods, brine shrimp, and ostracods, which bury themselves in the upper layers of the sea floor. Aladin has watched numbers of these crustaceans gradually decline since his first visit to the Aral Sea as a student 30 years ago, and now he hopes to see them rebound.
Once a successful water management program is in place along the entire Aral Sea watershed, scientists like Aladin expect to see further signs of life. For example, sturgeon have cruised along the bottom of the sea for thousands of years, hunting crustaceans in the muck, but when the crustacean populations declined, the sturgeon did, too. Aladin says that, fortunately, invertebrate eggs settled to the bottom of the sea like "Sleeping Beauty," delaying their development during the harshest environmental conditions. As the water level rose again, the eggs began hatching one by one, the first step in rebuilding the depleted food web.
Despite these encouraging signs, no one is certain whether the Aral can ever completely recover. "We managed to bring catastrophe a little bit back, but other parts of the lake are still a disaster," warns Aladin.
Illinois: Nutrient Farming
Returning water to the Iraq marshes and the Aral Sea brought immediate benefits to impoverished fishermen and subsistence farmers in those regions, but it may not be enough to guarantee long-term conservation. Some parts of the Iraq marshes, for example, will probably never be restored because they have become active sites for oil drilling and exploration. In the U.S., the faltering economy has recently been blamed for derailing restoration efforts in the Florida Everglades, where developers are still paving over wildlife habitat and sugar producers have long fought strict pollution controls.
Although there are no guarantees when political forces are at work, in the last decade practical-minded ecologists have tried to place monetary values on the services provided by wetlands to make restoration efforts attractive in economic terms. Until recently, such estimates remained theoretical, but one project in the U.S. aims to develop a market of "nutrient credits" provided by restored wetlands along the Illinois River.
Each year, agricultural runoff and municipal waste-treatment plants spew tons of nitrogen and phosphorous into our rivers. This nutrient overload triggers algal blooms that suck up all the oxygen in water bodies and damage ecosystems. For example, fishermen don't even bother going within 100 miles of the mouth of the Mississippi River in the Gulf of Mexico, where a massive algal bloom has created a dead zone that is mostly devoid of life.
In 2001, the Environmental Protection Agency announced that waste-treatment plants should reduce the nutrients they dump into waterways. Although there is no deadline in place yet, the agency has mandated that states develop water-quality standards for phosphorous and nitrogen. Large cities like Chicago can expect to spend several billion dollars upgrading their facilities.
Donald Hey, a civil engineer at the Illinois nonprofit The Wetlands Initiative, thinks waste-treatment plants should invest in restoring wetlands rather than making costly facility upgrades. "If we could restore a small fraction—let's say six to eight percent of the wetlands—that we once had here," says Hey, "we could relieve ourselves of huge flood damage losses. New Orleans, St. Louis, the upper Mississippi, the Sacramento, you name it. We could improve water quality dramatically and expand wildlife populations enormously."
Hey has proven how easy it is to restore Illinois wetlands at a pair of lakes called Hennepin and Hopper. First settled in the 19th century by soldiers who received chits for fighting in the Civil War, the land around Hennepin and Hopper lakes became aggregated over the years until only about seven or eight families controlled it. Around 1920, the families built a high levy around the property, drained the wetlands, and farmed the area until 2001. That's when The Wetlands Initiative, along with The Nature Conservancy and other nonprofit organizations, arranged to purchase the property and restore it.
|Bald eagles are returning to restored wetlands in Illinois. (photos.com)|
Workers combed the ponds and ditches on the property to eradicate several species of invasive fish that could inhibit recovery. Then, they turned off the pumps on the levy and let the marshes flood. Within a year's time, waterfowl were returning to the region, and seeds that had been dormant for 200 years were sprouting up from the soil. The area is now teeming with soft-shelled turtles, migratory birds, muskrats, and beavers. By the first spring after the flooding, Doug Stotz, a conservation biologist at the Chicago Field Museum, noted 139 species at Hennepin including the pied-billed grebe (Podilymbus podiceps), bald eagle (Haliaeetus leucocephalus), and black tern (Chlidonias niger).
Hey's effort is just one of many along the Illinois River that may one day serve as a model for the rest of the world. Current pressures on wetlands are only going to get more intense in the coming decades, and for these areas to survive conservationists are going to have to show that keeping the land intact is more valuable then destroying it.
—Brendan Borrell is a writer in Brooklyn, New York.
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ZooGoer 37(1) 2008. Copyright 2008 Friends of the National Zoo.
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