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Can San Francisco add 150,000 more people?

SF Public Press
 — Jun 19 2012 - 11:55am
Land’s carrying capacity under stress as Bay Area expected to add 2 million

In 1968, biologist Paul Ehrlich wrote the best-seller “The Population Bomb,” warning of mass starvation in the face of uncontrolled human population growth. Taken as alarmist at the time, the book nevertheless started a debate about the world’s limited natural resources and the human race’s voracious appetite.

Of course, we didn’t all starve, thanks in part to advancements in agriculture. But more than 40 years later, with the doubling of the world’s population, we’re faced with a different doom-and-gloom scenario: climate change. Ehrlich, now a population studies expert at Stanford University, hasn’t backed down. He says the government should actively discourage childbearing. “If you’re a patriotic American, you stop at two, and if you’re super-patriotic you stop at one,” he said.

That’s certainly not how most city planners, let alone Americans, are thinking. In places like San Francisco City Hall, officials enthusiastically embrace a pro-growth strategy to expand the city’s tax base, and create vibrant communities in blighted or underdeveloped areas. Most of that growth will come from new people moving into the city, since San Francisco has the smallest percentage of children of any major metropolitan center in the country — 13 percent.

But a larger population stretches resources, even in a dense, efficient metropolis. People create waste, and consume water, food and energy. They pollute the air with cars. And they encroach on the last vestiges of natural habitat.

Environmental resources begin to deteriorate when San Francisco’s natural ecosystems — and those of the larger Bay Area — reach their limit, or “carrying capacity.” The accepted regional projections over the next 25 years show the region increasing air pollution, exceeding water supplies, battling sea-level rise, and consuming more power — all due, in large part, to population increase.

“There’s not only a carrying capacity in terms of water and space,” said Tina Swanson of the Natural Resources Defense Council and former executive director of the Bay Institute, an environmental group focused on protecting the bay. “There’s also a quality-of-life carrying capacity. We don’t want to grow to a point where it isn’t a beautiful area, because then people won’t want to live here.”

Net growth in the city continues to rise, despite the shrinking average family size and the ups and downs of the economy.

The Association of Bay Area Governments predicts San Francisco will reach 969,000 people by 2035 — a nearly 20 percent jump above today’s 815,400.

The Bay Area, now nearly 7.2 million, would reach 9.3 million people by 2040 under that growth scenario. That amounts to 2.1 million more people at a growth rate of nearly 30 percent.

A California Department of Finance report in early May found that the Bay Area is the state’s fastest-growing region, thanks to the booming tech economy in Silicon Valley.

As the Bay Area struggles to meet sustainability goals, double-digit population growth presents a clear challenge to reducing the region’s ecological footprint. Residents must use resources more efficiently to counteract the addition of more than a million new residents. In many ways, it mirrors a challenge the planet is facing. Can population growth in San Francisco and the Bay Area be sustainable?

Planners argue that sustainable growth can be achieved if new development is funneled to the right places. Indeed, they say that the urban core — notably San Francisco, Oakland, San Jose and any other cities along BART or other rapid-transit lines — are the ideal places to put new people. They need fewer cars and the basic infrastructure is already in place.

Plan Bay Area, the growth blueprint approved in May by regional agencies, calls for San Francisco to create 92,410 new housing units by 2040 — 14 percent of all the new housing in the region. That’s a 29 percent increase over the city’s current housing numbers. If they are coming, the hope is, they might as well be coming to San Francisco.

But some environmentalists say population growth will inevitably deepen the effect on a local ecosystem. The region’s vulnerability to earthquakes and sea-level rise only heighten the economic and safety risk to those living along the coastlines and seismically weak ground.

“We may not want to face up to this, but the truth is we’re going to grow, because the human population is growing and the economy is growing,” said Richard Walker, a geographer at the University of California, Berkeley. “Then there’s the much larger question of why do we have to grow so much? The system we live in demands endless growth, and in that sense we’re trapped.”


San Francisco has dealt with a sudden population explosion before. In 1848, the Gold Rush turned a small Pacific outpost with fewer than 1,000 residents into a boomtown of 40,000 in just over a year, putting San Francisco on the map as a major commercial hub.

After World War II, returning servicemen in search of shipyard jobs brought their families to the city, leading to a housing boom that developed the sand dunes west of Twin Peaks. During the 1940s, the city grew more than 20 percent.

The new people and their industry left a deep footprint on the San Francisco Bay: Imported sand and moored ships created new land and a waterfront on top of mudflats. Sediment from gold mining destroyed wetlands, while toxic contaminants from mining and other industries polluted the waters. Invasive species were unleashed and changed the bay ecosystem.

These days San Francisco’s population growth is attributed to some of the same underlying causes. People migrate here internationally and from other parts of the country in search of jobs because the Bay Area is a desirable place to live. The city isn’t just passively letting them come — it has adopted a pro-growth strategy to strengthen its economic competitiveness with other cities. That strategy includes accommodating more people by increasing housing. That said, San Francisco has precious little open land, so new development opportunities are limited.

Ted Egan, San Francisco’s chief economist, said adding housing, particularly affordable housing, is wrapped up in the city’s strategy and its attempt to stabilize an unstable tax base. A tight housing market drives up wage inflation, he explained, without putting the cash in the pockets of the workers who are paying high rents.

“The money goes to those who they bought the house from, or to landlords,” he said. “To the extent that the city expands the housing supply, it will reduce housing prices in San Francisco. That’s the goal of the strategy.”


Guided by the city’s encouragement and direction, massive new housing redevelopment projects will be popping up on Treasure Island, Hunters Point Shipyard and Parkmerced over the next decade. Nearly 750 other projects, mostly residential or with a residential component, are in the planning and construction phases. They are expected to add almost 43,000 new housing units, according to the city’s 2012 Pipeline Report.

At the same time, San Francisco is trying to realize another goal: to become the “greenest city in America.” To that end, it adopted a “zero waste” policy to send virtually nothing to the landfill. Its climate action plan would reduce the city’s greenhouse gas emissions to 20 percent below 1990 levels by 2020. City agencies are increasing water and energy efficiency and are encouraging bicycling and walking.

To city officials, high growth and sustainability are not mutually exclusive. In a 2010 interview, Jack Sylvan, then director of the Treasure Island redevelopment project under Mayor Gavin Newsom, reacted strongly to questions about the sustainability of adding more than 7,000 people to the man-made Treasure Island, constructed on bay shallows landfill. The Treasure Island plans call for remaking the former military base into a high-density “eco-city” with high-rises clustered near a high-speed ferry terminal.

“The notion that this is going to happen somewhere else that’s better, I think, is fundamentally flawed,” Sylvan said. “You’re talking about fringe people who think that a back-to-the-land movement is our solution to an environmentally sustainable built environment.”


Yet some environmentalists see the city’s pro-growth agenda as anything but sustainable. The debate centers on “smart growth,” an urban planning concept that advocates building high-density neighborhoods, preferably in the urban core, and getting people out of cars to use public transit and start walking and bicycling.

Smart growth is seldom challenged, especially in the Bay Area, since it represents a progressive change in planning from the massive suburban sprawl of previous decades. But in certain environmental circles, smart growth is quietly criticized for ignoring population growth’s destructive effect on nature. Critics say smart growth will reduce the damage, but cannot erase it entirely.

“The notion of smart growth is an oxymoron,” said Dick Schneider, an activist in the San Francisco chapter of the Sierra Club since the 1970s. “San Francisco is already unsustainable, so further growth is only going to imbalance the situation even further.”

A 2005 white paper, “Unsustainable City,” produced by local planning and design firm MKThink, reasoned that San Francisco had an ecological footprint of 18 acres per person. That means 18 acres of land are needed to sustain the basic consumptive needs of an average city resident. Compared with the Bay Area’s 20.9 acres and the U.S. average of 23.6 acres, San Francisco doesn’t look so bad. The footprint analysis was based on a 2004 study by the Oakland-based think tank Redefining Progress.

MKThink takes San Francisco to task for not being “smart growth” enough in its housing density and independence from cars.

Schneider has a different reaction. Multiply 18 acres by the city’s population and that’s far greater than the size of San Francisco.

“That’s over 15 million acres of land and water to support the current population of San Francisco,” he said. “San Francisco’s acreage is about 150,000. So clearly, the San Francisco population is living beyond its means and is therefore unsustainable by any reasonable interpretation of the word.” 


Smart-growth advocates counter that halting population expansion isn’t a path to sustainability.

“If you look at Northern California, and if we care about issues like climate change and the environment, in fact, the best place to live is the San Francisco Bay Area,” said Egon Terplan, the regional planning director for the San Francisco Planning and Urban Research Association.

Terplan said San Francisco’s temperate climate requires less power for air conditioning and heating, while the city’s residents have a smaller environmental effect than those in outlying areas.

“What’s your feeling about the environmental impact that’s going to happen in the Central Valley and in Northern Sonoma County?” Terplan asked. “If the growth doesn’t come here, it’s going to be happening in other places. You can’t look at it in isolation.”

But is it San Francisco’s responsibility to solve the Bay Area’s sustainability problems? When considering sustainability, should improving local conditions take precedence?

“Every time I hear it’s going to grow this much, I want to challenge the premise,” said  Swanson of the Bay Institute. “The idea that we have to grow, when in fact natural resources may be limited and we have additional impacts … I think should be reevaluated.”

Regional smart-growth planning does sometimes work, said Sam Adams, the mayor of Portland, Ore., one of the best-planned cities in the country.

“Portland’s last city plan, developed over 30 years ago, focused on limiting sprawl, urban renewal, light rail (instead of highways), and helping to inspire new business sectors, including cleantech,” he wrote in an essay on, an environmental news website. “As a result, we have lowered total carbon emissions 6 percent while the rest of the U.S. has increased by more than 10 percent. And we’ve done it while growing our population and jobs.”


In the face of constant environmental pressures in the Bay Area, the smart-growth movement is sounding optimistic, the criticism about its blind spots notwithstanding. A shrinking region is a worse outcome, said Jeremy Madsen, executive director of the Greenbelt Alliance, a San Francisco-based anti-sprawl advocacy group.

“If you look at the alternatives, we could end up like Cleveland or Detroit,” Madsen said. “We’d rather be what we are.” 

Madsen said growth can spur innovative planning and infrastructure investment. That is happening in Oakland and San Jose, where strip malls and auto body shops — not high on any sustainability index — are being torn down and replaced with high-density housing and businesses.

“If it’s done right, you use development as a tool to develop,” Madsen said.

Greenbelt Alliance mapped out the underdeveloped land within the Bay Area’s urban footprint and found that as many as 800,000 new homes, virtually all the new growth in the next 25 years, could be accommodated without treading onto open space.

Perhaps the most hopeful note for environmentalists is the Bay Area’s historical success in digging out of environmental crisis while growing: the campaign to save San Francisco Bay. 

“The bay was a cesspool when I was a kid,” said Walker, the Berkeley geography professor. “There was no fishing to speak of in the bay, so some things are better. The sea otters and seals have made a comeback after being nearly extinct. There’s so much parkland that wasn’t there.”

Walker said “utopian goals” are sometimes achievable, with diligence, as the population booms: “You wouldn’t believe the changes that have been made even in my lifetime. The bay is so much more livable in so many ways, despite tripling in size.”

Read full coverage of Bay Area smart growth in the San Francisco Public Press Summer 2012 print edition, on sale at retail outlets around San Francisco and online.


Nice article, though the I find the basic premise a bit limited. Of course San Francisco can, and will, accommodate 150,000 more residents. The residential units in construction and design right now will accommodate almost 100,000 folks. More interesting is to ask "Can San Francisco add 1,500,000 more residents" which would give us a density in People per Square Mile of Paris. As a "thought experiment" something worth examining.

Funny, you drive an hour or so away from San Francisco and the whole world looks refreshing and natural. Densely packed cities aren't good for people's mental health. I think SF is a fine example of that fact.

Alison appears to be imitating the 'war correspondent look' in her photo. I don't believe that SF could handle another 150,000 people without some of them tumbling into the Bay.

I will be dead.


I would not want to exist in the coming too-crowded world.

Enjoy the next severe drought that will surely envelope your planned-for world.

Remember, kids, it is not the strong that will survive... the sneakiest do.

This article conveys the standard mindset on accommodating population growth via increased density - more planning restrictions, higher development fees, subsidies for certain types of development, and the necessary bureaucracy to support it all. Smart? Not very.

If the highest level of concern is waste, as it should be, the least wasteful way to achieve high density development is to implement a large increase in the excise tax on gasoline. Index the tax to inflation while we're at it. This encourages density from the bottom up, rather than top down, with a tax that comes with a very small economic loss (in public finance economic terms). The revenue from the tax can be used towards the necessary infrastructure improvements, and is spread across a wide base, rather than falling upon those who are new arrivals. I'd call that smart growth.

This was a very interesting think piece, Alison.

I think what you and your interlocutors fail to emphasize enough is that high density cities are far more efficient than sprawled out cities and suburbs from an environmental standpoint. In other words if we accept that the overall US population is going to keep increasing for a while yet, it's much better that people move to San Francisco than to new developments in Contra Costa.

I have to agree with Octavius that Dick Schneider ends up sounding like kind of an ass. The Sierra Club have turned into a crowd of Malthusian immigrant bashers for some time now, so it's hardly surprising though.

Yes, each SF resident may 'use' 18 acres of land, but a good deal of that is in the form of things like, I don't know, my parents cattle ranch and organic farm in Humboldt, which supplies food to probably several hundred San Franciscans while remaining rural and mostly wild.

The Parkmerced development "touts" sustainable infill, yet it ignores sustainable preservation based infill alternatives, and direct linkage to regional transit, instead delaying for 20 years for "tier-5" federal transit funds, and ignores how new lines of transit and cummalative growth proposals joining SFSU-CSU's masterplan and Stonestown's future growth and longer lineal development along Sunset Blvd., 19th Ave, and Junippero Serra Blvd. could allow density and development profit goals while creating new open-space, transit systems, and housing affordable to existing community members. The designs submitted lack real preservation based controls to include restoration of the garden units in Parkmerced which is a real energy consumptive design based on demolition of ALL the gardern units and ignoring the 11 towers which are seismically not retrofitted.

It is more ecologically sound to have people live in dense cities than spread out in vast suburban and rural areas where large amounts of infrastructure (roads, electric lines, gas lines, street lighting, public schools, and other public works projects must be built.

However, developing Treasure Island is not an answer. For Lennar to make money on the development, there must be 29,000 people living on TI. This will create a need for an additional lane on the Bay Bridge to handle the traffic. Ferry boats? Sure, a large 200-passenger ferryboat would need to make 300 trips a day to accommodate all those passengers.

Treasure Island simply is not practical to develop. The city should continue to lease out buildings and properties to entrepreneurs as they have been doing. It makes badly needed money for the city and the current system is sustainable. Redevelopment of Treasure Island is not sustainable.

Most Americans think that politically we're divided between Left and Right.

Well, not where it comes to population growth issues. There, Right and Left are united in their indifference to what most people think...and want. And their indifference to reality to boot.

Because when you have a shining vision, it can crowd out reality, which is ambiguous and messy. Shining visions are so much neater.

And here both Left and Right unite in denying that there's any such thing as overpopulation. So what if the world's human population is expanding at the rate of over 140 extra people per minute? So what if the Bay Area has doubled its population since the 1960's, turning all our freeways into parking lots when most people are going to/from work? So what if it would take 1.4 Earths to sustain Earth's current population with the current quality of life.

We're cantilevered over the abyss, with the porous aquifers of the world rapidly being exhausted--and when they are, they don't come back. Ever.

Yet denial reigns. The Left won't face overpopulation because someone said saying so is racist, and they'd rather let the world self-destruct than be accused of racism. The Right won't face overpopulation because they're like five year old boys who hate being told what they can't do. And the rest don't want to hear about it because it's, like, a total buzzkill, man.

So growth is good? Not one "growth" proponent quoted in this article will admit to there being any limit whatsoever, beyond which we'd have to say "whoa--that's it." If cancer could talk, it would talk like this. Think about it.

What about when the Bay Area is solid high rises stuffed with people, like Tokyo? Would that be cool with everyone? Just exactly who that lives here would benefit from such a scenario, apart from developers, realtors, and building trades unions? Everyone else would feel like they'd gotten the shaft--and they'd be right.

If inifinite growth isn't cool with you, then where should we set the upper limit? How about the current level, and tell all the regional planner busybodies to go help Stockton learn how to attract jobs for its residents rather than having them commute here?

Lastly, a shrinking population was presented as an unthinkable tragedy, invoking dystopian visions of depopulated Rust Belt towns. This is ridiculous. As the article indicated, the Bay Area boasts one of the finest climates on Earth, and a beautiful physical setting. It's not remotely comparable to Detroit.

When I moved here in 1966, with half the current population living here, not one resident said "Wow, this is tragic! Only three million people here! Life is almost unbearable with so few people, with the freeways actually usable, with elbow room between communities. Let's get three million more people to move here!"

I challenge anyone who was here then to say they said any of the above.

Leftists are eager to sacrifice our quality of life for the sake of the poor--at least if they're another race. Rightist are eager to sacrifice our quality of life for the sake of the rich, since there's no virtue in anything but profit, apparently.

If you aren't one of those, I suggest you start challenging the assumptions that are so obvious here: that growth is both inevitable and good; that we must sacrifice ourselves for someone else's ideal--that isn't even a valid ideal; that there's no such thing as overpopulation, climate change, ecocide, or all those other things nobody wants to think about.

Don't let the developers and the building trades unions push you around.

Schneider's argument is nonsensical. San Francisco doesn't need to internalize its whole carrying capacity within its limits. The city's boundaries are arbitrary. By his reasoning, if San Francisco annexed Napa the city would suddenly become sustainable.

Environmental impacts don't stop at city borders, and neither do the knock-on effects of city policies. If the whole country lived like SF, we'd reduce our needed "acreage" (itself an odd measure) by 24%. Adding more people to SF while making that city even more sustainable is a win for the environment; I don't understand how Schneider could perceive it as a loss.