SAN FRANCISCO — The United States must spend billions on its crumbling infrastructure to create jobs and lift itself out of recession, U.S. Sen. Barbara Boxer said Wednesday.

"There are more than 3,000 ready-to-go highway projects worth an estimated $18 billion that could be under contract within 90 days," Boxer, D- San Francisco, said at a news conference at Pier 1. "Those projects alone could support more than 600,000 jobs, and those are private-sector jobs."

The crisis is all too real, Boxer noted: Almost 190,000 Californians lost their homes to foreclosure in the first nine months of the year, atop of about 85,000 in 2007.

Assume a few residents per home, and "we're talking about probably the number of people who live in Delaware," she said. "We are talking about a massive displacement in our communities."

And she said the problem is will only get worse if California's unemployment rate, now at 7.7 percent, keeps rising.

"We are in a recession here; the question is how long and how deep a recession it will be," Boxer said. "If we can create 600,000 jobs and create them fast, we begin to reverse the trend. "... Everybody loves to get rebate checks, but we need jobs — that's the key, that's how we get out of a recession."

With Los Angeles topping the Texas Transportation Institute list of America's most traffic-congested areas, and with the Bay Area tied with Washington, D.C., for second place, California needs the new infrastructure anyway.

Water projects and making government buildings more energy efficient also would create jobs while fulfilling vital needs and protecting the environment. "Fighting global warming will create jobs and will save us money at the end of the day."

Boxer, who heads the Senate Committee on Environment and Public Works, said she's not sure whether a push for such investments will come during an upcoming lame-duck session of Congress or wait until after a new president takes office in January; that'll depend on how many seats Democrats take next week, and how Republicans react. Whatever stimulus bill lies ahead, she said, aid to states struggling with massive budget deficits — including California — "will definitely be on the table."

Inaction isn't an option, she insisted.

"The economy is on a downward spiral, obviously you want to act," she said. "We have to get back to a sound footing. The fundamentals of our economy are not strong. ... You've got to act on the emergency and then get back to fiscal stability."

Among those attending Boxer's news conference Wednesday were Contra Costa County Supervisor Federal Glover, East Palo Alto Mayor Patricia Foster and AC Transit Directors Chris Peeples and Joe Wallace. Boxer will speak on green job creation at an Oakland Chamber of Commerce luncheon today.

Reach Josh Richman at jrichman @bayareanewsgroup.com.