The marshlands of Iraq, which were drained during the early 1990s, are returning to their original state.
The marshland area has many channels which serve as byways
Under Saddam Hussein, the area of marsh was reduced to a tenth of its former size, as the government punished people living there for acts of rebellion.
The latest United Nations data shows that nearly 40% of the area has been restored to its original condition.
Drinking water and sanitation projects are under way, but the UN says that a full recovery will take many years.
Way of life destroyed
The marsh area, near the confluence of the Tigris and Euphrates rivers, was first affected by drainage programmes in the 1950s.
But a more serious threat emerged in 1991, when Saddam Hussein's regime began building an extensive network of dykes and channels to take water away from the marsh area, which originally extended for almost 9,000 sq km.
Satellite images showed that by 2002, the area had shrunk to only 760 sq km; an estimated 70,000 people were forced into camps in Iran.
"The near-total destruction of the Iraqi marshlands under the regime of Saddam Hussein was a major ecological and human disaster, robbing the Marsh Arabs of a centuries-old culture and way of life as well as food in the form of fish and that most crucial of natural resources - drinking water," United Nations Environment Programme (Unep) executive director Klaus Toepfer said in a statement.
According to Chizuru Aoki, Iraq project co-ordinator for the Unep, the situation changed rapidly with the end of Saddam Hussein's government in April 2003.
"Immediately after the fall of the last regime, local people started to breach dykes which had taken water away from the marshes and bring water back into drained areas," she told the BBC News website.
"And 2003 was a good water year, with lots of snow in the uplands and lots of rain."
Now, images show that around 37% of the original area has returned to its original state.
Back to basics
But water itself is only part of the story; people who have moved back to the area also need a secure supply of clean water, sanitation, and a reliable food supply.
Using an $11m donation from Japan, Unep is working alongside agencies of the current Iraqi government to install these services.
"The greatest need is to supply environmentally sound technology for the provision of drinking water," said Chizuru Aoki.
"One example of that is simply using plants to purify water - planting reeds, for example, which will remove pollutants such as nitrogen and phosphorus compounds from the water as they grow, using them as nutrients."
That will not work for all pollutants, however. One key issue is that much of the soil is highly saline, and Unep is looking at installing a desalination plant to produce drinkable water.
A full assessment of the local need has yet to be completed; and the UN acknowledges that it will take many years before the area is fully restored to its original condition - if, indeed, that is possible, with dams in Turkey, Syria and Iran reducing the amount of water which flows down the Tigris and Euphrates.