The final piece of the Hong Kong-Zhuhai-Macao Bridge was put in place in September, starting a new phase in the gigantic project.

An expansion joint weighing 35 metric tons was fitted on Sept 27 to complete work on a 22.9-kilometer section of the bridge.

Chen Guanghan, vice-dean of the Research Institute of the Development of Guangdong, Hong Kong and Macao, says the bridge will help Hong Kong to further expand its development space as it advances cooperation with the Pearl River Delta in Guangdong.

"The western part of the delta, which includes the prosperous cities of Zhuhai, Zhongshan, Jiangmen, Yangjiang and Taishan, still has huge room for expansion and cooperation with Hong Kong," Chen says. "Zhongshan, Sun Yat-sen's hometown, and Jiangmen and Taishan, the hometowns of many Chinese living around the world, also have rich tourism resources for further development."

He says the bridge will accelerate the development of Hong Kong's international airport and ports as well as its Lantou Island area.

Chen says Hong Kong should build more major shopping centers and malls on Lantou Island to meet the demand from the large number of mainland residents who are expected to visit after the bridge opens.

Song Haiyan, associate dean of Hong Kong Polytechnic University, predicts the bridge will positively affect the economies of all three cities.

Although he doesn't believe the bridge will bring a surge in tourist traffic, it will have a positive effect overall, presenting yet another option for travel between Hong Kong and the mainland.

Hong Kong lawmaker Lo Wai-kwok says the bridge will fortify the airport's role in the region, connecting the western Pearl River Delta and shortening the journey from Zhuhai to Hong Kong.

He is confident the bridge will be finished on time, as the most difficult part is now complete.

The project includes a 6.7-km underwater tunnel and a 22.9-km overwater bridge, the longest sea crossing in the world.

Construction of the Y-shaped bridge started in 2009 and will cost more than 10 billion yuan ($1.5 billion; 1.34 billion euros). It is part of the planned national highway network, linking the western and eastern banks of the Pearl River.

Once in operation, the bridge will cut the drive from Hong Kong to Zhuhai from four hours to 30 minutes.

The service life of the bridge is expected to be more than 120 years.

Contact the writers at zhengcaixiong@chinadaily.com.cn