Five years since winning its bid for the 2022 Winter Olympics, Beijing has stepped up its efforts to host a green Games with sustainability at the core of preparations.

With China resuming normalcy in all walks of life after the peak of the COVID-19 outbreak, Beijing has picked up its preparation for the 2022 Olympics with construction and renovation of facilities, with planning for Games-time management and designs for post-event operation well on track, according to organizers and construction regulators.

"We've resumed all preparatory work and are on schedule. We are confident that all competition venues needed for the Games will be done within this year," Ding Jianming, deputy director of the Beijing Major Projects Construction Headquarters Office, said on July 31.

Selected on July 31, 2015 as the world's only city to host the Winter Olympics after having staged the Summer Games, the Chinese capital is sparing no efforts to deliver on its promise to host sustainable Games with lasting legacies in all three zones－the city's downtown area, its northwest Yanqing district and co-host Zhangjiakou, Hebei province.

As a highlight of the sustainable approach, Beijing has taken advantage of the 2008 Games' legacy to re-purpose five venues used for the Summer Olympics downtown, such as the iconic National Aquatics Center, to host competitions and ceremonies in 2022.

The aquatics center, built for swimming in 2008 and known as the "Water Cube", has been transformed into an "Ice Cube" for curling after a yearlong renovation project, which involves filling the main pool with removable steel structures and making ice sheets above.

After staging a national junior curling tournament last December as a test, the venue now boasts convertibility to switch between summer and winter events, diversifying its business operation significantly, according to general manager Yang Qiyong.

"Thanks to the opportunity to serve the Winter Games, the project has benefited our business with a new sport and a wider range of attractions added to our portfolio," Yang said during a media tour at the center on July 28. 

Featuring new technologies and deliberate post-Games plans, some newly built Beijing 2022 venues, such as the National Speed Skating Oval, are casting new light on the sustainable future of permanent Olympic projects.

The oval is the world's first of its scale to use carbon dioxide as refrigerant to make and maintain a 12,000-square-meter ice surface for speed skating, replacing the use of the environmentally harmful substance Freon.

Plans are in place to turn the sleek venue into a sports and entertainment center for the public beyond 2022 by separating the giant ice surface into multiple rinks for figure skating, short-track speedskating and ice hockey sessions, according to venue operators.

"The design has made the venue pretty flexible to cater to different needs of different groups of ice sports fans. It will be an affordable choice for local residents to enjoy entertainment on ice after 2022," said Song Jiafeng, deputy general manager of the venue.

Linked by a new high-speed railway to Beijing downtown and Zhangjiakou, the suburban Yanqing district is also bustling with construction on Xiaohaituo Mountain, where the new National Alpine Skiing Center and National Sliding Center are being built.

Despite massive earthwork and engineering, the projects for the skiing center and the sliding track－a facility for bobsled, luge and skeleton－have taken vegetation protection into account.

Based on an evaluation conducted before construction, over 20,000 trees have been transplanted to a new 53-hectare forest park from the mountain ridges where ski slopes and sledding tracks are being built, according to property owner Beijing Enterprises Group.

"To protect the fragile ecological environment and ensure a minimal impact on forest and wildlife is the top priority of our construction work," said Liang Dedong, an executive of the group overseeing environmental protection and sustainable development.

"We are proud to see that over 90 percent of the transplanted trees have survived and flourished in their new home at the park."