The endless city on the Pearl River Delta
The Pearl River Delta in southeast China is becoming the largest metropolitan area in the world. Infrastructure planned with a view to the future and built to the highest quality standards makes the rapid growth of the Pearl River Delta possible. Along the estuary of the Pearl River to the South China Sea, Guangzhou, Shenzhen, Hong Kong and other megacities in Guangdong Province merge into a megaregion.
Typical rush hour in the city center of the 12-million-strong metropolis Guangzhou. The traffic is at a standstill on the six-lane Huangpu Avenue before it goes underground beneath Tianhe East Road which is also jammed. The sidewalks are crowded with pedestrians and bicycles have difficulty moving forward on their paths; honking horns and clouds of exhaust fumes are a strain to the commuters’ ears and drive their patience to the limits. An express bus leaves Tiyu Zhongxin bus stop (Tianhe sports center) – the world’s longest bus stop at 250 meters – every 10 seconds taking commuters from the city center to the suburbs, passing by a skyline of construction cranes and an endless stream of new buildings. On a normal day, these BRT (Bus Rapid Transit) lines transport around 800,000 passengers. The metro station in Tiyu Xilu also has clusters of people thronging in front of the entrances in order to get to Lines 1 and 3. Metro staff channel the masses of people using announcements and movable barriers. Day after day, the eight metro lines beneath Guangzhou transport around 4.5 million people – almost 8 million during peak hours – from the city center to one of the three long-distance railway stations or to Baiyun international airport, which is now China’s second-largest air hub.
Welcome to the Pearl River Delta, a rapidly growing conurbation that folds itself around the mouth of the river of the same name in the southeast of the People’s Republic. In addition to the historic hub Guangzhou – the former city of Canton – a further eight megacities, among them Hong Kong and Macau, as well as a number of smaller cities are located in this area with a surface covering 41,500 square kilometers. The UNO estimates in its report “State of the World’s Cities 2010/11” that 120 million people live and work in this megaregion. Factories, warehouses and banks in the Delta have supplied the rest of Asia and the world with goods and services such as popular electronic devices like iPhones and iPads. The constant increasing flows of commuters and goods are amalgamating the cities of Guangdong province into a boundless megacity in which residential and business sites merge with one another. Guangzhou grew at an average rate of 7.7 percent per annum between 1990 and 2006 and the neighboring cities Dongguan and Shenzhen at 13.1 and 20.8 percent respectively.
Model projects for megaregions
The lure of large cities in other wealthy developed countries is comparably modest. According to UNO estimates, the worldwide urban population will only increase by 1.5 percent annually by 2030. In North America, 80 percent of the population already lived in cities in 2010. In Western Europe this figure amounted to 77 percent. Both continents experienced their urbanization boom long ago. The historically grown metropolis Paris, for instance, accommodates approximately one quarter of France’s population and generates a quarter of the country’s gross national product. The financial hub New York is home to one in 12 US citizens and generates one in 12 dollars of the nation’s economy.
Such rapid growth is only possible if cutting-edge infrastructure is planned with foresight and promptly implemented. The corresponding plan formulated by the Chinese government is an ambitious one. By 2020, the entire delta is to transform into a uniform economic and residential area in which the different cities are not further than one hour of travel time away from one another. Traffic will be moved increasingly to the railway service, and power and communication networks as well as water supply and sewage disposal systems are to be upgraded to the state of the art.
Tunnel boring machines (TBMs) made by Herrenknecht will play an important role in realizing this vision – deploying its TBMs both in Hong Kong’s granite rock and in the sedimentary soils of the Pearl River. These construction projects, with an investment volume worth more than 215 billion euros, also serve as an example for megaregions beyond China’s borders, showing how the infrastructural development of a megacity may be planned and implemented in the 21st century.
Linking the around 150 infrastructural projects to connect the Pearl River Delta is phenomenal. The plan is to build around 2,800 railway kilometers for highspeed trains, 2,200 railway kilometers for intercity connections and 1,000 kilometers of metro routes by the year 2020. Professor Zheng Tianxiang taught at Sun Yat-Sen University inGuangzhou. As a scientist at the Center for Studies of Hong Kong, Macao and the Pearl River Delta, he has been concerned about the region’s infrastructure and transport for more than a decade. He thinks that integrating current networks is the first necessary step to adapt the infrastructure for people and goods to the region’s impressive dynamism: “Building three networks in one – that means the seamless connection of high-speed railways, intercity connections and metro networks – will change people’s lives fundamentally. Railway transport should be both the backbone of and the link to air traffic, truck and water transport. It is a good plan, even if some details are still missing. However, I think that the planned extension will only meet the needs of the current number of people, while the region will continue to grow.”
He continues “The government’s development plan is a good point of departure to keep pace with the estimated growth. As soon as the large, integrated network is finished, people will no longer be restricted to living and working in the same city. This mobility for people and goods is mainly provided by one thing: rail.” According to Zheng, investing in this innovative infrastructure means preparing for several large trends: on the one hand, the transition from mere export production to the manufacturing of higher quality products such as cars, airplanes, and electronics, and on the other hand, an improvement of the quality of life in a modern conurbation. Several projects being realized with Herrenknecht tunnel boring machines are a good example of the rapidly developing integration of a booming agglomeration.
Construction work in a sensitive environment
In the 4-million-strong city Huizhou, situated at the heart of the Guangdong province, two tunnels are being excavated for the Guangdong Intercity Railway. After its completion in 2014, the almost 100-kilometerlong route will connect the two cities Dongguan and Huizhou. “The task of the S-570/S-571 machines is to excavate a 2.9-kilometer-long tunnel,” explains Wang Zhao, Vice General Manager of China Tunnel Construction Company, standing in front of the launch shaft located in the city center between office towers and a public sports park.
The Earth Pressure Balance Shield has a diameter of 8.8 meters. The machine’s cutting tools loosen the soil, which is then mixed in the excavation chamber with the already existing plastic soil. Further removal of the soil is precisely controlled. This generates a support pressure to balance the groundwater and earth pressure on the cutting wheel and to prevent the collapse of the tunnel face. This is important as many buildings in Huizhou are more than 100 years old and they would be seriously damaged in the event of any ground disturbances of more than a few millimeters during tunnelling. In Huizhou, the TBM will initially advance half a kilometer beneath the Dongjiang River, a tributary of the Pearl River, and then cross Huizhou’s old city over a length of one kilometer, before ending at one of the 17 city train stations at the West Lake.
“The geological conditions are not too complicated, but when crossing beneath the river and in the old town, we have to keep to a tight limit concerning soil subsidence. Herrenknecht offered us exactly the technical support we needed to use the right TBM for the project.” says WangG Zhao, Vice General Manager, China Tunnel Construction Company (CTC). As soon as the intercity train is running at 160 to 200 kilometers per hour here, new opportunities will open up for people. “Huizhou is calmer and greener than other cities in the delta. The more reasonable costs of living make the city attractive for inhabitants of Shenzen and Guangzhou to move here,” says the CTC manager. “This will boost Hiuzhou’s economic development.”
Numerous tunnel boring machines are being used simultaneously
In Guangzhou, the effects of a better infrastructure network have already become visible. Since 1997, the city has opened eight metro lines with 144 stops and a length of 236 kilometers. “In a city with so much traffic and so many traffic jams, there is no alternative solution to a rapid and efficient metro network,” says Zhu Weibin, Vice General Manager of Guangzhou Metro Corporation. “The advantages are obvious: environmentally- friendly operation, speed, comfort and a high volume of passengers. The construction was a wise decision which saves time for everyone in Guangzhou every day.”
“The Metro system has become the city’s main mode of transport. The Metro network will extend to a total of 800 km by 2020, with over 200 km planned in the next 5 years.”
Zhu Weibin, Vice General Manager Guangzhou Metro Corporation
The municipality is already working on the massive extension of more than 200 kilometers of additional route over the next 5 years. In a third phase, Guangzhou’s metro network is to grow to 800 kilometers in length. The aim is to seamlessly interlink suburbs, satellite towns and all important transport hubs. The authorities want to minimize any disturbances to inhabitants and businesses during the construction phase; this is why Herrenknecht TBMs are the best solution, according to Zhu. He adds, “An old Chinese proverb says that before a good harvest, one has to be equipped with the best tools. That’s why we use cutting-edge technologies for metro construction.”
To reach Herrenknecht in the Pearl River Delta is easy because the company has two plants in Guangzhou: Herrenknecht (Guangzhou) Tunnelling Equipment Co., Ltd. (HTE), located in the Free Trade Zone, and Guangzhou Herrenknecht Tunnelling Machinery Co., Ltd. (HTM), in the city district of Nansha. In addition, there is an office in Hong Kong, Herrenknecht Tunnelling Equipment Limited. Since 2005, the two plants have delivered more than 120 TBMs, of which 28 have gone to Guangzhou and a further 25 to Shenzen, a planned city with 9 million inhabitants located directly at the border to Hong Kong. Both sites not only manufacture new cutterheads and disc cutters, but also, TBMs with diameters of up to 15 meters have been assembled there. “We have established the standard for excellent TBM quality in China,” says HTM Managing Director Rainer Hirsch. “If there are challenging construction projects or difficult ground conditions, customers will ask for our machines.” For that reason, a third manufacturing hall was opened in Nansha recently, and the area can accommodate one more hall. The workforce for the manufacturing of cutterheads, assembly and field services in Nansha has grown from 45 to more than 400 members over the past 5 years. In view of the transportation projects planned till 2020 and beyond, Hirsch sees a continually strong demand for Herrenknecht TBM technology.
Demanding tunnel construction
If engineers in the Pearl River Delta talk about demanding tunnel construction, they are mostly referring to the 7-million-strong city of Hong Kong. The finance and business center at the mouth of the South China Sea is one of the most densely populated cities in the world. Under its rows of office towers and apartment blocks, there is a closely meshed network of metro lines and numerous supply channels. A further milestone is to be completed in 4 years: the Express Rail Link (XRL) which connects Hong Kong with Shenzhen, Guangzhou and other major mainland cities. Also thanks to the work of a total of six Herrenknecht TBMs, the XRL trains are to run every 3 minutes during rush hours, which means that the travel time into the delta’s heart will be reduced to 48 minutes from currently 3 to 4 hours by bus or almost 2 hours using the KTT railway.
“What are your personal highlights from the XRL project?” “The climax of my career will be the inauguration of the XRL to Shenzhen and Guangzhou. West Kowloon station will become one of the biggest underground stations in the world.”
David Sorton, General Manager, XRL-Tunnel, MTR Corporation in Hongkong
The construction pit for the West Kowloon terminal station clearly shows that the express link closes an important infrastructure gap. The XRL station is not only situated in a booming residential and business quarter with views of the city’s landmarks. Thanks to the connection to the express train, Hong Kong’s airport with its more than 50 million flight passengers a year will be connected by rail to the neighboring cities in the delta and via the Chinese highspeed railway network to Shanghai and Beijing. The new station, which is completely underground, offers space for 15 platforms on four levels and expects around 100,000 passengers daily, starting on the very first day. “West Kowloon will become one of the biggest underground stations in the world. The routing poses some challenges for us,” reports David Sorton, general manager of XRL Tunnel, MTR Corporation. The two Herrenknecht TBMs excavating to the West Kowloon terminus, part of the Kowloon development area where the tallest hotel is located, will have to cope with different ground conditions including granite. The XRL terminus interchanges with a section of the West Rail Line which was opened in 2009. Part of the line, the Kowloon Southern Link beneath the city district of Tsim Sha Tsui, was also excavated with a Herrenknecht machine.
At Hong Kong’s northern border with Shenzhen, four Mixshields will connect the two large cities by building tunnels that also cross the Mai Po wetland biotope. The XRL final station in Guangzhou is South Station inaugurated in 2010 which is reminiscent of an airport with its 28 platforms and a freely suspended hall construction. From here, travelers may change directly to the metro or to one of the rapid trains going to all other destinations in the country. The region’s inhabitants are looking forward to the new railway link with great expectations. “My life will be more convenient, no doubt,” says Cai Yujian who works for the Cosco shipping line. “If the price is reasonable, this is hard to beat.” Miles Gu, who lives in Guangzhou but works for the Asia Regional Office of Generali Insurance in Hong Kong during the week, sees this just as positively. His journey home will be reduced to less than one hour. He is considering moving away from Guangzhou and buying a house right by the new Express Station to reduce his travel time to Hong Kong to only 15 minutes. “Then I can conveniently commute to Hong Kong and back home every evening, instead of seeing my family only at weekends,” says Gu.
Better quality of life combined with economic growth
A better quality of life as well as smooth trade and flexibility in the entire Pearl River Delta megaregion is also the aim of further megaprojects in Hong Kong which the special administrative region under Chinese sovereignty will support with investments of at least 15 billion US dollars in the coming 10 years. The city is further extending its existing dense network of transport and supply arteries to channel the growing flow of people and goods as smartly as possible. According to surveys made by the Guangdong Urban and Rural Planning and Design Institute, 1.4 million people cross the border between Hong Kong and Shenzhen every day.
Peter Weiley from the Australian construction company Leighton, who completed the Kowloon Southern Link of the West Rail Line on schedule with the help of a Herrenknecht TBM, is well acquainted with the growing mobility requirements for people and goods in Hong Kong: “Locals have been making jokes for 30 years saying that Hong Kong will be a wonderful city once finished. Now the goal of removing the bottlenecks to allow uninterrupted and rapid transport ways in and around Hong Kong is within our grasp.”
Other cities in the Pearl River Delta may learn from Hong Kong’s experience in infrastructure developments where tunnels are being excavated just a few meters beneath a constantly busy metropolis without disturbing residents or businesses. Experts forecast that China’s infrastructure is facing a material growth spurt in order to provide for the country’s rapidly progressing urbanization. According to estimates made by the McKinsey Global Institute, a total of one billion Chinese people will live in cities by 2030, which corresponds to a demographic increase of 350 million people in the coming 14 years. To cope with this boom, the country needs, among other things, more than 170 new public transport systems. Currently, the state development commission (National Development and Reform Commission, NDRC) has approved metro projects in around 30 cities – a great opportunity for companies that have experience in demanding tunnel construction. “Now is the prime time for metro construction in China and it will probably last until 2030 at least,” says Zhu Weibin of Guangzhou Metro Corporation. “Our cities are growing rapidly and the transport situation is becoming worse and worse. In order to solve this problem, many new lines must be built.”
Early planning which considers good interlinking with other means of transport and, above all, future growth, as well as professional implementation together with experienced partners are the key to success. “We have built 145 kilometers of tunnel in Guangzhou using Herrenknecht expertise. Herrenknecht has rendered the most important contribution to metro construction in our city and in the whole of China,” praises Zhu. “The company is the trustful partner we can rely on in all construction projects. If problems occur, they stand in at the right time and solve them, working side by side with us.”
We are ready!