WUHAN, Sept. 1 (Xinhua) -- In the eyes of Hu Sheng, the men's beach volleyball test event for the upcoming 7th Military World Games here on Sunday has brought memories of both childhood joy as well as misery caused by pollution.

Hu, 72, has been living in Wuhan for over 60 years. Over the past decades, he has witnessed the rebirth of the Yangtze river beaches -- from natural waters into hills to tunnels made of industry ash, then back to nature again. Now, the beautiful beach is set to host volleyball matches of a world-level sports event.

At five, Hu moved to Wuhan's Qingshan District with his parents and tens of thousands of other migrant workers to build the Wuhan Iron and Steel Corporation, one of China's largest enterprises in the iron industry.

"Daijia Lake, by the beach of Yangtze river, was our paradise at the time, with lots of fish to catch and lotus roots to pick," Hu recalled.

Along with the growth of Wuhan Iron and Steel, small plants such as cement plants and power plants were built nearby the Daijia Lake.

Photos from the time show industrial waste water mixed with coal ash being discharged into the lakes around the Yangtze river, bringing Hu's natural paradise to an end.

Over the next 30 years, Daijia Lake disappeared. The piles of dumped ash continued to grow, into a place that locals referred as "Daijia Hill".

"Ash floated in the air. Some of my neighbors suffered respiratory problems. We had to keep our doors and windows closed in windy days," Hu said.

A few years later in the latter part of the 1990s, the city of Wuhan began to expand, and coal ash was in demand as material for buildings and construction.

"The waste ash hill became hot; trucks swarming here to carry it away to make bricks," Hu recalled. The Daijia hill was quickly dug in tunnels, which later filled with garbage and construction waste.

The rebirth of Daijia Lake started in 2013, when ecological development was listed as a major task in China's overall plan for ecological development.

The restored area exceeded 500,000 square meters. More than 30,000 trees were planted in the park. Problems like dust, barren soil, and water pollution were also solved.

"We are glad that the beach of Yangtze river we live nearby became green again. Now we can watch beach volleyball matches here," Hu said.