Turkey's Ulubey Canyon is known to be the second longest in the world, after the Grand Canyon.

It is considered a national treasure and a popular tourist destination.

However, in recent year, the stunning rock formations and their surroundings have been tainted by toxic wastes from nearby industrial areas.

Yusuf Erdogan was born in Ulubey where his family has lived for three generations.

He said 30 years ago, the stream near his home used to be crystal clear.

He told Assignment Asia: "We have laboratory results showing heavy metals in the water. The color, smell and appearance suggest that the water is unsuitable. They cannot be used for agriculture or as drinking water."

After losing their source of income from agriculture, many Ulubey farmers had to learn new skills and search for employment.

In the meantime, officials tried to reduce and prevent pollution in the area.

However, undoing the damage that's already been done will certainly be an ongoing challenge.

Assignment Asia is CGTN’s award-winning current affairs program featuring long-form stories and documentaries on some of the most pressing issues in the region. The show airs Saturdays at 1330 and 2130 GMT, with replays every Sunday at 0630, Monday at 0130, and Tuesday at 0530.