By Kiet Do

FREMONT (KPIX 5) — Amazon and Facebook are increasing their footprints in the South and East Bay.

Amazon has secured a lease at a huge delivery hub located at 707, 807 and 907 N. McCarthy Blvd. in Milpitas. The three warehouses comprise 343,000 square feet of space that the company will use to process arriving shipments from tractor trailers and place them in delivery trucks.

Milpitas Mayor Rich Tran said commercial real estate on the Peninsula and in San Francisco has become more expensive compared to the east and southeastern parts of the Bay Area.

WATCH: CBSN Bay Area – 24/7 Digital News Channel from KPIX 5

“The cost per square foot doing business is prohibitive for a lot of companies and if you look at where the housing’s at, it only makes sense that companies are looking east,” said Tran.

The new Amazon hub will bring nearly 300 jobs to Milpitas. To balance the growth, Mayor Tran said the council has enacted wage theft protections and is pushing for more affordable housing.

“Anytime we can bring in jobs, that’s a good thing. We only have to look back 10 years to when there were no jobs. And I think we’ll take 2019, rather than 2009,” said Tran.

In Fremont, construction crews are busy at work renovating several parcels with a dozen buildings near Highway 84 and Thornton Avenue, soon to be a sprawling new campus for Facebook. Some employees are already working at the site.

Once complete, the portion of the Ardenwood Office Park, bounded by Dumbarton Circle and Kaiser and Campus Drives, will comprise roughly 1 million square feet of office space for the social media giant, which can accommodate several thousand employees.

Several buildings in the area are, or will soon be, available for lease, including the vacant Tesla Building on Dumbarton Circle. And if Facebook acquires those as well, its footprint could swell to 1.3 million square feet in the Bay Area’s fourth largest city.

The campus expansion was largely seen as a move to take advantage of the East Bay’s talent pool, possibly shorten commute distances and the slightly lower home prices along the I-880 corridor.

Olivia Taylor, who works near the new Facebook campus but commutes from Hayward, is worried about the onslaught of traffic once Facebook begins to ramp up operations there.

“I was talking to one of my colleagues and was telling her traffic was going to be twice, triple. Really bad,” said Taylor.

Mayor Lei released the following statement regarding the new Facebook Ardenwood campus:

“The City of Fremont has long been aware of the value that Ardenwood Technology Park offers tenants including the strong real estate market, 2.7 million square feet of R&D space, a strong talent pool, and ease of access to transportation. To anticipate community and future workers’ needs arising from Facebook’s current significant expansion in Ardenwood, we have been working with Facebook to strategically plan solutions rooted in both housing balance and increasing public transportation options in North Fremont such as the future Dumbarton Rail Corridor. We welcome the opportunity to work in lock step with all businesses looking to expand in our thriving city while acknowledging the need for careful planning to continue the quality of life Fremont residents have always enjoyed.”

Facebook didn’t respond to a request for comment.