Water levels in the marshes fluctuate with the season but more than 60 percent of the area has been restored to levels from before they were drained. Nature Iraq estimates they could eventually bring back 75 percent of the marshes. The biggest threat is lack of water. Dams in Turkey have stopped the seasonal floods the marshes relied on and Iran has also limited the flow of water. Drought and inefficient farming practices have also taken a toll. Yasser Faisel/America Tonight

The south is one of the safest regions in Iraq and there have been no attacks in the marshes in recent years. Children here though suffer from extreme poverty, lack of access to schools, clean water, sanitation and health care. Plans for mobile clinics that would have provided health care have fallen through. Iraq has a severe shortage in rural areas of doctors and nurses. courtesy: Jane Arraf

White flamingos, pelicans and mallard ducks are among the birds that stop over in the marshes. Nature Iraq is trying to start an ecotourism industry that would bring bird watchers to the area during the migratory season. courtesy: Jane Arraf

Putting up the arch of the guesthouse. The same design is found on clay tablets 5,000 years old. Bending and tying the bundles of reeds provides a tension to the arch that keeps it strong. Unlike concrete, the reed houses are relatively cool in the heat of summer and can be easily warmed in the winter. courtesy: Jane Arraf

The frame of a reed guesthouse called a mutheef is under construction. The guesthouses can be built in a day and are normally communal and used for celebrations, visitors or meetings to solve disputes. This one is being built by a group of families who moved back to the marshes last year from the city. Yasser Faisel/America Tonight

Cooking bread over reeds is a technique that has remained unchanged for thousands of years. The plastic shelter is a fish camp, used by local fishermen to spend the night on one of the manmade islands. courtesy: Jane Arraf

A woman and her son sit in front of a reed fire. She's the older of two wives - married to a man with 11 children. Her husband buys and sells water buffalo. Many families who moved away when the marshes dried up keep a concrete house in the city but spend most of their time in reed houses on small islands, taking care of the water buffalo. Yasser Faisel/America Tonight

A traditional reed house on a man-made island. The islands are made by piling dirt on layers of reeds in the shallow water. Wealth in the marshes is measured by the number of water buffalo a family owns. Water buffalo milk, which is extremely rich in fat, is the main source of protein apart from fish. It's also used to make cheese and a very thick cream known as gamar. Yasser Faisel/America Tonight

For harvesting reeds, the boats are essentially the same design as in ancient Sumarian clay tablets but fitted with outboard motors. In very shallow water, the boatmen or women use poles to move forward. Clearings among the reeds serve as waterways, serving the same purpose as roads on land. Yasser Faisel/America Tonight

Girls cut reeds in the central marshes. The reeds are used as building materials for houses and mats, feed for the water buffalo and fuel for cooking fires. Cutting them also prevents the reeds from choking the marshes and increases the fish population. Although men do most of the fishing, women and girls do a lot of the other work in the marshes, including harvesting reeds, tending to the water buffalo and caring for the children. courtesy: Jane Arraf

Two men push a boat out into the shallow waters that have once again become a stopping ground on the migratory bird route from Africa. Drying the marshes removed the reeds and fish that the birds needed. Now that the water is coming back, birds are also returning. This area was near the biblical Garden of Eden, the confluence of the Euphrates and Tigris rivers, where fish, plants and birds provided everything needed for the world's first civilization to flourish. courtesy: Jane Arraf

A local girl living near Chubaish. In spite of the oil fields surrounding the marshes, the area is still one of the poorest in Iraq. Only a little more than a third of children stay in school past the fifth grade. Many of them work with their parents and don't go to school at all. Many of the people living here became refugees after Saddam drained the marshes to prevent infiltration from neighboring Iran and to punish the people in the south for a failed uprising against him. courtesy: Jane Arraf

A woman in the market in the main town of Chubaish sells fish caught in the marshes. Carp used to be a staple fish but because the water here has become more saline after the marshes were dried, new types of fish more resistant to saltier water are thriving. Local people catch the fish in nets thrown from long canoe-like boats although some use electricity to stun the fish. courtesy: Jane Arraf

Jassim al-Asadi, an Iraqi engineer from the marshes, stands on an embankment near the Euphrates River. When Saddam Hussein was toppled al-Asadi and Azzam Alwash brought in construction equipment to break some of the dirt embankments that had prevented water from flowing into the marshes from the Euphrates. A decade later more than half the marshes have been reflooded and fish, birds and people are coming back. Yasser Faisel/America Tonight

Azzam Alwash is an Iraqi-American engineer who returned to Iraq in 2003 after Saddam Hussein's ouster to help local people break the barriers built by Saddam and reflood the land. The group he founded, Nature Iraq, has successfully lobbied the country's government to declare part of the marshes a protected area: the Central Marshes National Park. Alwash is working on more than a dozen other national parks throughout the country. Yasser Faisel/America Tonight

Twenty years after Saddam Hussein drained the marshes of southern Iraq, the water and the people are coming back. The people who live there -- known as Marsh Arabs or Madan in Arabic -- have a unique culture - much of it unchanged for 5,000 years. Residents of the marshes make their living from reeds, fish and water buffalo. Yasser Faisel/America Tonight

Twenty years after Saddam Hussein drained the marshes of southern Iraq, the water and the people are coming back. Journalist Jane Arraf traveled to the historic area for America Tonight.

On just a few feet of water in southern Iraq, the world's first civilization was born.

Azzam Alwash, an Iraqi-American engineer, knew these wetlands and their importance as a boy and he's determined to see them restored.

"On the edge of these marshes is where civilization started,” Alwash said. “This is where writing was invented. This is where agriculture was first started. This is where the wheel was invented. This is where Abraham was born. So, in a sense, it doesn't belong to Iraq. It belongs to the rest of the world."

In the 1990s, Iraqi dictator Saddam Hussein changed the landscape by draining these marshes and driving out the inhabitants. In one of the biggest engineering projects of the past century, Hussein had dirt barriers constructed all along the Euphrates River to hold back the water. This was done to prevent infiltration from neighboring Iran and to punish people here for a failed uprising against him.

Huge dams in neighboring Turkey also stopped the seasonal floods that had created an ecosystem thousands of years old.

Azzam left Iraq in the late 1970s and built a career as a soil and environmental engineering consultant in California. But in 2003, he returned and started Nature Iraq. Azzam and his colleague Jassim al-Asadi used their engineering skills to help break embankments built by the Hussein regime along the Euphrates River and bring the water flooding back.

When Hussein fell in 2003, the locals and Nature Iraq cooperated to open a dike, al-Asadi said. But there are still environmental challenges.

The marshes are close to Iran, which controls some of the water flow. Even worse from an environmental point of view, there's oil under the marshes waiting to be tapped. But the main worry is getting enough water to keep the marshes alive.

"We have less water than we used to do – we have worse quality than we used to do and we have increasing demands – be it agriculture, be it industrial be it domestic and as it stands before the marshes were declared a national park it was basically if we have water that's extra we'll give it to the marshes,” Azzam said. “At this point in time with the Iraqi government declaring it a national park it has a legitimate demand to sit at the table and ask for a legitimate share of the water."

Along with the water, Azzam would like to see people flowing back here as well.

"Imagine you're a birder and you come here. We could build this into a nice bird-watching center,” he said. “You can see as far as the horizon. Look at this! It's gorgeous!"