NEWARK, California (Reuters) - Vacant industrial land near salt marshes and a derelict rail bridge seem like an odd setting for the beginnings of a lifestyle revolution in scenic California, but planners in the San Francisco Bay suburb of Newark view it as just that.
With an eye on the state's new land-use laws to cut carbon output, Newark's city council just voted to convert 200 acres owned largely by chemical companies into a development that should set the trend for a state bent on decarbonising its economy, the world's ninth largest.
The marshes could be turned over to birds, satisfying environmentalists, or paved over with single family homes, like most of the Bay Area.
Newark planners envision something different, which might satisfy both - or neither: 2,500 new homes, mostly townhouses and apartments, built within walking distance of stores and schools and connected by a new train to jobs across the Bay.
That trip would put commuters right in the heart of Silicon Valley, where 1950s suburbs with two-car-garage homes grew out of orchards to create a California dream that has endured decades.
California's success in reshaping that dream, leaving behind big convertibles cruising past strip malls, will determine its future. The state population has doubled in four decades to nearly 38 million and may hit 50 million by 2050.
The state that invented the freeway often looks like a parking lot at rush hour, and not just in the biggest cities.
"The way we developed in the last few decades is definitely not sustainable," said Hasan Ikhrata, executive director of the Southern California Association of Governments, the largest metropolitan planning organization in the country.
"The future is going to be single-family homes in smaller lots, multi-family homes and a more urban style of living," he said. "We are going in a totally different direction now."
The state has become a global champion in the battle to stop climate change, adopting a raft of laws and regulations to reduce planet-warming greenhouse gas emissions to 1990 levels by 2020, then by an additional 80 percent by 2050.
That's an extremely tall, if not an impossible order.
A study by energy consultancy Enduring Energy calculates California must generate 90 percent of its electricity from carbon-free sources like wind and solar; retrofit existing power plants with as unproven carbon capture technology; and move virtually all its cars to electric power to hit its 2050 goal.
"It's a re-engineering of our society," said Bryan Hannegan, the vice president for environment and renewables at the Electric Power Research Institute.
How California lives and how it builds is a big part of the solution. While industry, from factories to refineries, get the most attention from climate change foes, cars and buildings are top polluters, California has found.
Transportation accounts for about 40 percent of the state's carbon output, while commercial and residential buildings account for a quarter - more if construction is included.
So developments like the one in Newark tackle carbon emissions by creating smaller, better built houses with conveniences so close no one will need to get in a car.
"We're trying to be a post-suburban community," said Terrence Grindall, Newark's community development director.
The cornerstone of California's pursuit of a low-carbon economy is a 2006 law, known as AB32, which set the 2020 target.
After years of cajoling local authorities to build more homes near public transit - including a lawsuit to enforce one city to do so - the state in 2008 passed SB375, which requires its 18 metropolitan planning organizations to show how they will meet greenhouse gas reduction targets through integrated land use, housing and transportation.
"Going forward, state and federal transportation dollars can only be dedicated to projects that are consistent with the sustainable communities plan," said California Senate President pro Tem Darrell Steinberg, author of SB375.
"I call it a hard carrot. It's a carrot, but if it hits you, it might sting," he said, adding that California is now the leader in sustainable development in the country.
The profile of the typical new home in California is being flipped on its head. Between 1985 and 2010, 61 percent of all houses built in the state were single-family homes and 39 percent were multi-family ones, such as condominiums and apartment buildings.
Between 2010 and 2035, Southern California planners project, 68 percent will be multi-family and 32 percent single family.
There is ample room for scepticism. California's exurbs mushroomed during the last economic boom, turning now-bankrupt Stockton into a Bay Area suburb with an hour and a half commute in each direction.
Building high-density communities will only alienate buyers, said Joel Kotkin, a professor of urban development at Chapman University in Orange, California. "You'll end up in a situation where we have housing that people don't want," he said.
Tea Party activists nationally have campaigned against sustainable development, seeing it as a threat to property rights.
And then there are the environmentalists and homeowners who do not want the last patches of undeveloped land clogged up with dense housing that's bad for wildlife and property values.
"I wouldn't want to live in something like this. People are going to be packed in like sardines," said Margaret Lewis, a member of the Citizens Committee to Complete the Refuge, a group dedicated to protecting the San Francisco Bay's remaining wetlands, which opposes the Newark project.
Having to battle environmentalists for more sustainable projects is not what developers had in mind.
"There's an identity crisis in the environmental movement," said Peter Calthorpe, an urban planner who designed models for the state's regional planners. Environmentalists in the 1970s were the vanguard opposing sprawl. And now, he says, they provide cover for anyone who opposes dense urban housing.
The early signs are that once such developments are built, they can be popular.
On a chilly evening in midtown Sacramento, developer John Hodgson points out two former auto showrooms and a vintage fire house that have been converted into mixed-use buildings, with restaurants at street level and apartments and offices above.
The top floor of one such building, steps from the Capitol, holds Governor Jerry Brown's weekday residence.
Hodgson said demand is being driven by the young "creative class," who eschew the car-centric, big-yard lifestyle of their parents. But the parents - "empty nesters" including Hodgson himself - also like living downtown.
When Byron Buck's kids left home, he and his wife left their five-bedroom suburban house for a downtown Sacramento loft.
"The big epiphany for me was I don't think about traffic anymore," Buck said. "That psychic energy of not having to think about that is huge."
Sacramento is now developing abandoned rail yards into what will be the country's largest mixed-use development.
If there is a place made for the car, it is Southern California, with its highways, driveways and drive-in everything. Half the state's population lives in six counties hugging the beaches and stretching into the Inland Empire full of affordable single-family homes. Cheap gasoline fueled growth.
"When people moved to the suburbs of Los Angeles in the past, energy costs were not a factor in the decision making of households because gas was $2 a gallon. That equation has changed now that prices average $4 to $4.50," said Southern California planner Ikhrata.
Between seniors, who will nearly double in number to 20 percent of the population by 2035, and young professionals, there is a sea change in demand.
"If you combine these two groups, more than half of the population will aspire to totally different lifestyles than what has been considered normal," Ikhrata said. "The single family home on a large lot is a thing of the past," he said. (Reporting by Braden Reddall and Rory Carroll in San Francisco; editing by Peter Henderson and Todd Eastham)