The new 55-km Hong Kong-Zhuhai-Macao Bridge (HKZM) – the world’s longest sea-bridge, links three main cities in the greater bay Area of China (formerly called the Pearl River Delta). The Bay Area is China’s economic powerhouse, accounting for 14% of China’s GDP in 2017, but only 5% of its population. China’s economy has been slowing down, and there are problems related to inequalities in wealth, an ageing workforce and increasing pollution of air and water. It is hoped that the bridge will help the Greater Bay Area to further develop. The Chinese government’s ‘Made in China 2025’ plan aims to up-grade its high technology industries and reduce its imports. It also hopes to make the Bay Area in to a large-scale version of USA’s high-tech Silicon Valley.
Construction of the bridge was started in 2009 and cost around $17 billion (120 billion yuan). Some 50,000 workers and engineers were involved in the project. The bridge is designed to last for 120 years. The bridge is high enough to allow ships to pass underneath.
The bridge also contains a 6.7 km submarine tunnel – the longest in the world for vehicle traffic. The seabed of the Pearl Delta is formed of 50 m deep unstable sediments. These sediments are easily affected by waves and tidal movements. The tunnel section of the bridge includes rock and gravels bases that have kept subsidence of the whole structure to less than 10 cm. Construction was hampered by many events, including Typhoon Hato (August 2017) and Typhoon Mangkhut (September 2018).
The bridge will improve accessibility in the Bay Area. For example, the drive time from Zhuhai to Hong Kong will be reduced from four hours to 45 minutes! It is estimated that by 2030 around 30,000 vehicles will use the bridge daily. Although there are a number of ferry services in the bay Area they are relatively slow and offer a limited night-time service. The bridge will make Macao and Zhuhai much more accessible than previously. It is believed that this will help with their economic development – most investors to the region want to be within three hours drive time of Hong Kong, and the bridge now provides that.
Some environmentalists have criticised the scheme as it has led to a decline in the white dolphin population near to the bridge.
Time will tell how the bridge manages to change the fortunes of China’s most economically developed region. It is a major engineering success.