Can Saddam's desert be a Garden of Eden again?

When Azzam Alwash was a boy he went duck-hunting with his father on the Mesopotamian marshes. They took an old wooden boat and rowed south from his home in Nasiriyah into one of the largest wetlands in the world – the land of the Marsh Arabs, which some believe is the origin of the story of the Garden of Eden.

This week, watching TV images of the battle for Nasiriyah from his new home in California, Alwash wonders at the different landscape. "I look at the pictures of the bridges over the Euphrates. All the land behind used to be endless bullrushes and reedbeds stretching for hundreds of miles. But now there is nothing green. It is totally gone," he says.

The difference is Saddam Hussein. After the 1991 Gulf War he drained most of the marshes and diverted the Tigris and Euphrates, the two great rivers that once watered them. It was an epic work of destructive civil engineering that turned the ecological jewel of the Middle East into a scrub desert and drove out most of the 50,000 Madan, or Marsh Arabs, who had joined the abortive post-war uprising against him in 1992.

Alwash, who is, like his father, a civil engineer, would probably have had to work on the draining if he hadn't left for the US in the late 1970s. But now he has plans to bring back the landscape of his childhood.

Alwash and his American wife, Suzie, a geology professor, are behind a plan to recreate the marshes. Their Eden Again project has gained support from the Pentagon, US aid officials, the UN Environment Programme (UNEP) and from the Madan themselves.

The couple have recruited hydrologists, ecologists and engineers to draw up plans for what would be the largest wetland rehabilitation ever attempted. Those plans will be published within the next two weeks.

Time is short. Some 93 per cent of the marshes are now a dry, salt-encrusted wasteland, and scientists say the rest could be gone within two years.

The UNEP scientist Hassan Partow says blocking the new drains and diversion canals could be the easy part of reclaiming the wetlands. Dams being built high on the headwaters of the Tigris and Euphrates in Turkey and on the Karkheh in Iran are cutting flows into the marshes.

Much of the last remaining wet area, the Hawizeh marsh close to the Iranian border, has dried up in the past two years because an Iranian dam has stopped the flow on the Karkheh. According to the British ecologist Mike Evans of Birdlife International, the Hawizeh is the last refuge for species of plants, fish and animals that could recolonise the marshes. If those species – including animals found nowhere else, such as the smooth-coated otter – are lost, then the natural ecosystem of the marshes will no longer be able to regenerate, however much water is poured in.

At their fullest extent, the freshwater lakes, reed beds and endless waterways of the Mesopotamian marshes once covered an area almost the size of Wales, stretching north and west from Basra towards Baghdad. Half a million people relied on it to grow rice, catch fish, hunt otter and birds, gather reeds and graze water buffalo.

They included the Madan, who were made famous in Wilfred Thesiger's 1964 travel bookThe Marsh Arabs, and many more people, such as Alwash and his father, who lived round the fringes of the marshes.

President Saddam changed all that in 1993 and 1994 when he built a series of giant canals that diverted the rivers away from the marshes, and installed drains to empty the rest.

He was partly following British colonial plans to "reclaim" the marshes for agriculture, drawn up in 1951. But President Saddam never grew a thing in his drained marshes. He emptied it of people as well as water – a job completed by torching villages and pouring poisons into the marshes.

Turkish dams aided him. According to one analysis, they have cut flows of water into Iraq by some 20 per cent, and could eventually take 50 per cent.

The big questions now are: How much of the ancient marshes can be recreated? And if it can be done, would the Madan want to go back? Is this, in other words, all a romantic dream for a lost world, buoyed up by the enthusiasms of wetland scientists and politicians anxious for a visible "peace dividend"?

Tom Crisman, director of the University of Florida's Centre for Wetlands, says: "It's probably the most ambitious wetland rehabilitation ever attempted. And we will be trying to put back a culture as well as an ecosystem. I don't know of a precedent for that. But it can be done, I am sure."

Scientists at UNEP believe that a successful rehabilitation will require both a new treaty to share the waters of the rivers and a new Iraqi government willing to allocate some of its share for the marshes.

Politics, as much as hydrology, may ultimately decide the fate of the marshes. But while that plays out, Alwash has a dream. "My wife and I go kayaking on the weekends here in the US," he says. "I keep telling her: one day you'll see what a real wetland is. My dream is to go kayaking on the Iraqi marshes with her and my kids. Just as I went with my father."