Urban sprawl has been anathema to California housing planners for the last 10 years or so. As they passed law after law eliminating zoning for single-family residences and emphasizing high rise buildings and other infill housing near mass transit, the old California pattern of building outward became passe.

Maybe not anymore.

Two prospective massive new developments emerged from obscurity into the realm of distinct possibility over the last few months.

One would be in mostly rural portions of Solano County, an often-overlooked area covering much of the ground between Sacramento and the San Francisco Bay area and stretching south toward Stockton. The other would extend Fresno to the southeast.

Together, the two proposed developments (neither as yet has won even a single government agency’s approval) could account for as many as 85,000 new housing units, mostly single family. That would provide a sizable chunk of the 1.8 million new dwelling units in one estimate of current housing need from the state Department of Housing and Community Development.

But some words of caution are advised here: Tejon Ranch. Housing advocates rejoiced in 2021, when the big land company with huge amounts of vacant property atop the Grapevine area between Los Angeles and Bakersfield, got an OK from Kern County. But less than two years later, a Los Angeles County judge sent the project back to the drawing board, and its approval process may now drag on for many years.

Still, in this era when every new law seems to seek a knockdown for existing housing and commercial buildings in exchange for large new apartment buildings with stores, gyms and other commerce on the lowest floors, there may be broad appeal to brand new homes on what has been agricultural land.

In Solano County, a group of Silicon Valley billionaires including Lorraine Powell Jobs, the widow of Apple Corp. co-founder Steve Jobs, and other venture capitalists, quietly bought up more than 55,000 acres (78 square miles) of pastureland wind farms and other low-density development. They appear willing to pay whatever penalties are needed for taking the land out of agricultural use, where the state’s Williamson Act has long given much of it preferred tax status in exchange for remaining rural.

This projected new city, which would have more than 10,000 acres of parks, could eventually become the largest town in Solano County, where Fairfield is the county seat and other significant locales include Rio Vista, Vacaville, Dixon and Suisun City.

To change the use of so much land would require first a vote of the entire county and then a slew of other permits from state and regional agencies. So this is years away, but promises lots of affordable housing, plus European-style homes for wealthier buyers. And plenty of profit for the billionaire investors.

Then there’s the Southeast Development Area on the edge of Fresno, a mostly-rural area of about 9,000 acres whose prospective developers promise a series of “walkable” neighborhoods in what would be one of Fresno’s most sprawling suburbs. Plans tentatively call for each neighborhood to have its own elementary school, community garden, shops and parks. Plenty of public transit is also proposed.

This one also would need public votes and myriad government permits before going forward.

In both places, local opposition has already formed. Solano County Supervisor Monica Brown, a former schoolteacher, told one reporter that “We’re growing food and helping people (now). Why would you stop economic growth like that? Why would they spend $800 million and not be transparent about it?”

Brown referred to the five years of secrecy investors maintained while becoming Solano County’s largest landowners. Their spokesman responded that secrecy was needed to prevent speculative land price increases.

At the same time, school officials and others worry about “gaping holes” in infrastructure if the southeast area plan goes forward.

But prospective developers of both areas say they will take care of all those concerns.

So it will initially be up to local voters to decide: Do they want new, but traditionally California-style developments near them, or do they want to leave things alone and thus have the state continue stressing urban infill? Or could these possible new suburbs be harbingers of other new developments in California deserts and the Central Valley?

Email Thomas Elias at tdelias@aol.com.