OAKLAND (KPIX) – Kaiser unveiled the plans for its massive new national headquarters on Monday.

Dubbed the Thrive Center, it will span nearly 1.7 million square feet. That is more than the Salesforce Tower, but it will stand about half as tall. It is a huge building, and it is an even bigger deal for Oakland.

“The word of the day is big,” declared Mayor Libby Schaaf. The project is so big a lot of Oaklanders spent Monday just trying to imagine what’s about to land here between Broadway and Telegraph.

“This is amazing,” said Oakland resident Ben Lang, looking at the renderings. “I’ve lived in the city for 40 years and I’ve never seen anything like this.”

The big building is the result of a big decision from Kaiser.

“At the end of the day we can think of no better place to stay than Oakland California. So we’re here,” said Kaiser Permanente CEO Bernard Tyson.

The health giant, Oakland’s largest employer, will not only stay in Oakland, it will consolidate staff now spread across seven downtown office buildings, in one brand new national and regional headquarters.

“We, in fact, have projected that we will save, annually, about $60 million,” Tyson explained.

It also means Oakland will have 1.6 million square feet of office space available when Kaiser moves across town, and Mayor Schaaf was already inviting businesses to stake their claim on that space Monday, doing some bragging about Oakland’s current desirability.

“We all remember several years ago when Kaiser was even thinking about relocating its hospital outside of Oakland,” Schaaf said. “So today is such a great day.”

So it’s not just the biggest building in town, but a something of an exclamation point in a downtown where big things seem to be happening all over the place.

“Cranes everywhere, new buildings, new housing, new structures everywhere,” says Oakland resident Leshia Gwen. “I notice even the old structures are getting face lifts. Oakland is thriving.”

Kaiser expects to break ground on the Thrive Center next year, with completion expected in 2023.