KANDAHAR, Afghanistan - The crumbling remains of Tarnak Farms sit on the outskirts of the largest NATO airbase in southern Afghanistan, the sprawling monument of western military might visible in the background.

It has been many decades, though, since much farming has been done on this parched tract of Kandahar province.

An army barracks during the Soviet era, the farm became one of three al Qaeda training camps set up in Afghanistan under the guidance of Osama bin Laden. Lore has it that the 9-11 hijackers were trained at Tarnak Farms and in the days after the terrorist attacks, U.S. bombs rained down on the compound.

Tarnak Farms was also the scene of the April 2002 "friendly fire" deaths of four Canadian soldiers. They were the country's first casualties of the Afghan war, killed by two U.S. Air Force F-16 fighter jets by mistake during a night training exercise.

Now the government of Canada hopes to rehabilitate the notorious area, literally returning it to its roots as part of its aid spending in Afghanistan.

"Everything needs to be fixed," said Lisa Vandehei, manager of Canada's $50-million Dahla Dam signature project.

The massive dam north of Kandahar city was built by the U.S. in the 1950s and its spider web of canals helped turn Kandahar into the bread basket of Afghanistan.

But years of war, neglect and lack of funding have left the irrigation system in total disrepair. In a subcanal near the Tarnak Farms compound, south of the city, water stains on the concrete wall of a decaying culvert show the water level is down four to five feet from its heyday.

Approximately 70 per cent of the capacity of the dam is lost to broken infrastructure. The canals and subcanals that bisect the province are filling with silt and garbage.

The dam itself needs repairs but first the canal system will be cleared and repaired. That work began in January, after extensive testing and studies of the system, and will continue during the October-November and January-March "dry seasons" when farmers don't need water flowing.

More than 500,000 cubic metres of silt and debris must be removed from the canalways. Unexploded ordnance litters the landscape, and Canada has earmarked another $2 million in funding for removing USO from the Dahla canal system.

Near Tarnak, equipment is just arriving to begin irrigation training for local farmers on six seven-hectare plots. They will also receive training on making the best use of the water they have, growing better staple crops and reaping higher-value resources like saffron, mint and honey.

The contract has just been rewarded for a separate, $4.7-million project to build the Kandahar Regional Agriculture and Rural Development Institute at Tarnak Farms, part of a master plan to have various nations and aid organizations contribute to rehabilitating the region.

There have been unique challenges and setbacks -- including a private security dispute -- but work has continued and the project is still on track to be completed by the end of 2011 -- with a lot of hard work.

"This is a massive job," Vandehei said Friday. "It's on track in Afghanistan because we're putting everything we have into this. We're putting a lot into this, a lot of sweat equity."

Fear is a factor but Vandehei said only two communities have said no to the work, and the project has not been targeted by the Taliban.

"Not so far, no."