TAIPEI, Taiwan (TheStreet) -- The Beijing suburb of Daxing is known now for super-sized watermelons. But in four years it will open a new international airport, making China's capital the world's busiest civil aviation hub.

If Chinese airport history is an indicator, the project will bring opportunities for foreign investors: airlines, aircraft makers, airport construction contractors and high-end retailers with outlets next to captive crowds of people awaiting flights. So which companies stand to benefit most?

"China certainly needs more airports to meet rising demand and is undertaking the largest such program in the world," says Kerry Brown, director of the University of Sydney China Studies Centre. "In addition, pumping money into infrastructure projects for local government is always a good way to keep GDP going, and that also takes a part in these decisions."

The new airport south of downtown Beijing will be designed to handle 620,000 passenger flights and 2 million metric tons of cargo per year, state-run China Daily said Dec. 19, citing the central government's National Development and Reform Commission. 

The plan also calls for 14 maintenance areas and a terminal building with 700,000 square meters (7.535 million square feet) of floor space.

Once the $13.1 billion project opens, Beijing will be able to process 72 million passengers a year through three airports within the city limits. Beijing Capital International Airport, today's flagship, already ranked as the world's second-busiest airport last year with 83.7 million passengers, China Daily notes. Many were foreign business travelers who face time-hogging congestion today at existing airports.

But business travel is just the start of a long, lucrative trip for foreign investors. Although Chinese state-owned contractors will all but surely lead construction of the new airport, they normally pick foreign subcontractors such as Japanese elevator builder Hitachi (HTHIY) -- already ubiquitous in China -- for specialized technology. (Hitachi spokespeople did not answer a request for comment.)

The new airport's chief contractor may pick subcontractors used in the past for similar work in China, says Eric Lin, Asia transport analyst with UBS Investment Research in Hong Kong.

"If you're talking about suppliers and materials, there are a lot of foreign suppliers," Lin says. "State-owned enterprise contractors will look to them when they need technology."

Later, foreign airlines will want some of the new airport's spaces, expected to cover 150 parking aprons. As of November, Chinese citizens had taken 100 million outbound trips, the state newspaper says.

Whether non-Chinese airlines get spaces depends on negotiation skill and possibly membership in airline alliances that include major Chinese airlines, Lin says. One such alliance, Skyteam, includes foreign carriers Delta Air Lines (DAL) and Air France KLM (AFRAF) .

Airport expansion also dovetails with China's long-term quest to buy more aircraft, like Hong Kong-traded flagship carrier Air China's order with American supplier Boeing (BA) for 60 planes priced at a total $6 billion and to be delivered from 2016 to 2020. Boeing publicists were unavailable for comment.

A Chinese government-backed contractor will also manage retail at the new airport, Lin says. That company is likely to bring on foreign brands that already sell in airports under the same management, like Burberry (BBRYF) and Estee Lauder (EL) . They're positioned to capture gift buyers who are otherwise stuck waiting for takeoff.

"It is a bit surprising that Beijing's airport is at capacity, but I guess this shows just how quickly air travel is expanding in China," Brown says.

This article is commentary by an independent contributor. At the time of publication, the author held no position in the stocks mentioned.