This Chinese mega-city has more people than Canada or Australia

China’s Pearl River Delta is swallowing up nearby cities.

As the largest urban area in the world, the region features a population of roughly 42 million housed inside a 2,700-square mile perimeter.

The Pearl River Delta is made up of nine cities each boasting populations above one million. And China is combining them all into one giant mega-city.

China skylineBobby Yip/ReutersA man walks during low tide at Lau Fau Shan, famous for its oyster culture, in Hong Kong’s rural New Territories July 3, 2015. The fast developing city of Shenzhen on mainland China is seen in the background.

The PRD began as a rural region with an agriculture-based economy. Urbanisation didn’t take off until the early 1990s, when factories and big business flocked to the region and brought with them millions of new residents.

In 2008, the Chinese government revealed its plan to combine the nine major cities in the PRD — Shenzhen, Dongguan, Huizhou, Zhuhai, Zhongshan, Jiangmen, Guangzhou, Foshan, and Zhaoqing.

By 2030, China plans to spend RMB 2 trillion ($US322 billion) in the hopes of drawing more people from the outskirts of the megalopolis to inside its border. The population is expected to rise to 80 million with a total GDP of $US2 trillion. (The entire US GDP is just shy of $US17 trillion.)

The key question is whether China can make the mega-city merger sustainable. The country has started construction on bridges and railways to connect the cities, both with each other and the neighbouring metropolises.

Hong kong bridgeBobby Yip/ReutersThe Hong Kong-Zhuhai-Macao Bridge (HZMB), which will link the three cities in the Pearl River Delta, is seen under construction off Hong Kong’s Lantau Island, China, June 12, 2015.

In a sense, the region has a lot of room for growth.

Roughly 64% of people in the PRD still live in non-urban areas, according to data from a recent World Bank report.

But the consequences of urbanisation — lagging public transportation infrastructure and a scarcity of affordable public housing — will no doubt leave others stranded on the fringes. And there are also those who will be displaced by rapid construction.

This woman, for example, was swept up in the consequences of large-scale urbanisation when workers accidentally knocked her house down during demolition.

RTR2ZP6GStringer China/ReutersHuang Sufang reacts as she sees a part of her house being taken down by demolition workers at Yangji village in central Guangzhou city, Guangdong province.

In other parts of the PRD, urbanisation proceeds at unequal rates, leading to odd juxtapositions in housing complexes, like this small structure surrounded by high-rises.

China houseJoe Tan/ReutersMigrant workers chat at their temporary house near a construction site in Guangzhou, Guangdong province.

It will be a challenge in the remaining 15 years of China’s expansion plan to resolve pockets of inequality. East Asia already has eight mega cities and 123 cities of between one and 10 million people.

If trends hold, those numbers will only continue to rise.

“While this transformation is going on, there is still an opportunity to set the course of urbanisation on a more sustainable and equitable path,” the World Bank report states. “Within a few decades, this window of opportunity will close, and future generations will be left to deal with the consequences of how we urbanise today.”

NOW WATCH: 11 facts that show how different China is from the rest of the world

NOW WATCH: Briefing videos

Business Insider Emails & Alerts

Site highlights each day to your inbox.

Follow Business Insider Australia on Facebook, Twitter, LinkedIn, and Instagram.