By Len Ramirez

SAN JOSE (KPIX 5) — Business is booming in San Jose, waking up what some say was a sleepy downtown area.

“It used to be a commuter downtown they used to call it.  People would come downtown for work then they would leave it, making it a ghost town after dark.  It’s not like that anymore,” said Matt Day, CEO of Founders Floor, a high-tech incubator with offices in San Jose.

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There are more people on the sidewalks at lunchtime, more building activity and more company logos are popping up on downtown high rises.

“I think we’re seeing an unprecedented amount of grown in San Jose right now,” said Eddie Truong of the Silicon Valley Organization.

One sign of the upturn in business is in the low office vacancy rate, which fell below 10 percent for the first time in decades, according to Phil Mahoney of Newmark Knight Frank, a commercial real estate brokerage firm.

The second of two River Park Tower buildings opened as a spec building amid the big recession in 2008. Much of it sat vacant for years.

But the last of its 16 stories just got filled. It is now brimming with tenants, including several high-tech startups.

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“It puts an exclamation point on all the activity that’s been happening in downtown San Jose for the past two to four years,” Mahoney said.

Tenants moving in want to be a part of downtown’s emerging scene.

“The Google announcement kind of turbo charged things, but now there’s a lot of momentum for an urban environment that employees want to be at,” said Mahoney.

Matt Day says younger workers want to walk or ride to places for lunch or after work.

“We’re having a lot more selection of restaurants downtown. Not just fast food, but someplace where they can go, sit down and enjoy with the team,” Day said.

But Truong said two things still threaten the city’s long term economic growth: transportation and housing.

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“We can fall under the weight of our success, if we don’t build the necessary infrastructure,” Truong said.