Tag Archives: seismic risk

Natures of San Francisco

A man in the city,” wrote American novelist William Gass, “has no natural thing by which to measure himself.” But self-measurement is increasingly difficult to gauge in an age of global warming, and increased catastrophic weather. We are with less of a rudder than in the past. When Gass wrote, two thirds of the way through the last century, he was describing cities on the east coast of the United States with the wry bitter logic of a longtime midwesterner. Most cities were clearly bounded, we had no sense of urban sprawl, even if the United States was still–as it is now–distinguished by the highest per capita urban areas of any industrialized nation in the world. If San Francisco was predominantly green, bounded by the Bay and Pacific Ocean, dotted with parks and green space, although its development has been confined by faultiness, as much as by environmental strictures on urban growth and neighborhood improvement associations.

If we imagine interconnections of the Bay Area by analogy to transportation infrastructure, we might approach a deeper understanding of the migration patterns and natural presence that continues amidst the growth of ground impermeability and urban footprints. There was a deep tie to nature present in San Francisco, after all, back when some fifty daily ferries that in the 1930s, a century ago, shuttled an annual fifty to sixty million passengers across the Bay waters, and a quarter left the water through the Ferry Building daily from the hundred and seventy ferries making daily landing. The bay offered a deep structures of Bay Area before the Bay Bridge and Golden Gate definitively reshaped the webs of transbay travel, that we might argue offer a means to reconnect to the land. It was not only for reasons of public transit that Lewis Mumford bemoaned the end of a relation to a rich ecosystem on the bay waters for which the Bay Area opted in budding a bridge linking Oakland and San Francisco, which quickly sent “a once unnecessary volume of private traffic between them, at a great expense in expressway building and at a great waste in time and tension, spent crawling through rush-hour congestion.” The volume precipitated a demise of past public transit webs, hardly resolved by the underwater tunneling of the Bay Area Rapid Transit at huge expense.

Cross-Bay Ferry Transit in San Francisco Bay and Ferry Building, Post Card sent 1930

The casualties and damages on the Bay Bridge since the bridge was built have sent many to hospitals and injured more, unlike the pleasures of open-air transit across bay waters gleaned in from tninted postcards. If the old hand-tinted photographs of an urban “sky line” suggests a closer and far more intimate relation to bay waters on ferry lines, it offers an important point of departure to take stock on the persistent presence of nature in the city by the bay. We often sense nature only through the calls of owls and morning doves, and increasing number of families of crows searching for food, is there not a therapeutic benefit of trying to map the relation to natural habitats across the ever-expanding ecological footprint of urban space, even as so many commuters daily drive to and around San Francisco in our cars, more than by foot? Even if the massive freeway once designed to run along the bay was cancelled, only by mapping the resilience of a relation to nature can we take stock of the rich biodiversity that exists in the city, in hopes to cultivate it both on the ground and in our minds.

The place of nature of San Francisco may have constricted, but cartographers have recently realized its importance to map. If measurement has been outsourced to numerous devices–from not only height and weight, but caloric intake, income, carbon footprint, and racial identity, the mapping of the proximity between nature and the city in the Bay Area is concentrated in San Francisco, bound by beaches, hills, and habitat. As a Midwesterner, Gass was aghast at the notion of nature in the city, and of the reduced relation to nature in urban life: “Nothing can live and remain free where he resides but the pigeon, starling, sparrow, spider, cockroach, mouse, moth, fly and weed, and he laments the existence of even these and makes his plans to poison them,” Gass writes with acid specificity, winding up to the final punch: “His parks are potted plants.” The reservoirs of green that interrupt the urban footprint of San Francisco are hardly afford a coherent ecosystem. But the relations of urban and rural that have animated many west coast cities has created a demand to reconsider and to remap relations of “urban” and “rural” that were once clear dichotomies, pushed by the increased absence of open spaces that once surrounded cities like Portland, Seattle, or San Francisco.

Indeed, if the Golden Gate Natural Recreational Area, a Marin-based park that hosts two thousand plant and animal species over nineteen distinct ecosystems shares the largest boundary with an urban environment of any national park, the focus on conservation that brought together what has been heralded as a “new urban park” was created by cobbling together public and private lands that redefined the value and relation of the constellation of interconnected parks to urban space that presents a compelling model for a new urban park” outside of the growing city, and a new relation of nature to the city than Gass experienced. Awareness of the biophilic needs of urban inhabitants for contact with urban greenspace, that has prompted active redesign urban environments in an overpaved world, responding to evidence greenspace reduce stress and mental illness, mapping the presence of nature in the city cannot be reduced to parks. As our contact with nature and the natural is endangered or at risk of deterioration, the perspectives that open space around San Francisco offer on the ravines of built space make the case for remapping urban space and open space a Nature in the City has worked to do, focussing not on human settlement of built space, but privileging the inversion of how habitats intermingle with the built environment of a city like San Francisco, shifting a tacit prioritization implicit in all maps. San Francisco is, of course, the beneficiary of the huge area of the nearby Delta, through which over 40% of run-off from the Sierras have long flown, bringing with them sediment from the mountains that flows to the sea, creating alluvial deposits that have made it a nexus for fifty mammal and fish species, from salmon to striped bass to sturgeon to steelhead trout and endangered smelt, and a stop on the Pacific flyaway from Canadian geese to sandhill cranes, and a habitat for over two hundred bird species, twenty reptiles and amphibians, attracted by sediment-rich marshes of the watershed’s historic wetlands and open lands. Can we map their presence in the city nearby? Or do we not have to do so better than in the past?

1. In ways that invite the recession of the “city”–just barely visible as a skyline a full three quarters across the view form Loma Alta Open space, in Marin–the Nature in the City map inverts the equation, by asking us to view the city in its relation to surrounding habitat that still presents a living ecosystem that enters the city’s paved streets.

San Rafael Bridge and San Francisco Skyline Seen from Loma Alta Open Space, Marin CA

Long before politicians railed against cities, asking where the heart of the nation’s heart lay, this icy put-down summoned the identity of the interior to dismiss the paltriness of urban parks as poor replacements for the nature world. But the if the built centers of San Francisco have grown in recent years–both in its downtown skyline and neighboring Oakland–as any departing airplane can see–the maps we make of our changing cities demand we attend to how they invite us to explore and navigate urban space in all its dimensions–including the role of the city as an ecosystem, as much as a built structure.

We bristle in San Francisco at the dismissal of our built environment, or verticality as a measure of cosmopolitan urbanism. From the seat of the departing plane, one might forget that the city not only borders significant greenspace across the Bay, but that San Francisco and the East Bay are living habitats–an area we who live there are more sensitive as a site of potential loss, whose greenspace demands preservation as an ecology that many city dwellers often fail to note. As more mindful outfits like the Nature Conservancy seek to preserve a public consciousness of the need to mitigate incursions of urban areas into the urban greenspace, we might ask not only how to convince public planners and developers to be more conscious of such incursions–and the serious problems that they create for fire, as well as compromising ecology and habitat. While the most rigorous conservation plan. based on the Bay Area “Greenprint”–a model soon to be expanded to all California–suggests the proximity of critiical ecosystems in need of protection in their “Mitigation Wizard” that takes a base map of sensitive species’ habitat–

–the intersection it creates between habitat and potential extra-urban growth is designed to better help us negotiate the futures that the Bay Area might meet. Tracking the density of species in critical ecosystems lying in proximity to the Bay Area’s urban agglomeration, different levels or criteria of conservation can be entered against current natural science observations of sensitive habitats of up to one hundred species around San Francisco’s wetlands, forests, and grasslands that can create a dialogue between areas ecological sensitivity in close proximity to urban growth. The hope is to offer a baseline for mitigating the effects of urban growth–and to elevate those concerns to a level comparable to the attention to property that is increasingly seen as vulnerable to sea-level rise, the aridity, fire risk or soil subsidence as consequences of warming and temperature rise, acknowledging local ecosystem integrity as consequences of anthropogenic change.

2. There is a need for pictorial maps to inspire us to orient ourselves to habitat in urban space. We who live in the city are more accustomed to see a unique sort of habitat, and a confluence of not exactly rural but open space and green corridors in an urban environment. Even as vertical crowding may eclipse its green, the urban ecosystems they nourish prevent the symptoms of urban dysphoria associated with built environments, and notwithstanding threats of seismic disturbance or sea-level rise. Novelist William Gass’s rather bone-chilling evocation of the coldness of rural isolation eclipses the real work of nurturing deep ties to a abundant ecosystems in San Francisco’s built space. And in an age when trees, and urban greenspace, face threats of car pollution, extreme weather, and the uprooting of trees to make way for construction sites or trim branches for urban safety or interference in above-ground power lines in many Bay Area cities, the value of absorbing CO2 and preventing floods by absorbing water have created a virtual boom of greening urban space.

Increasingly, we are attendant to the urban habitat they offer, beyond the cult of verticality as a metric of urbanity. Trees have been increasingly seen as presenting a basis for the future flourishing of cities and sustainability of urban space, with the growth of greening projects across the developed world: since 2007, an active New York City overseen by Bloomberg rooted over a million trees in urban space, and have taken root in London, where Mayor Sadiq Khan aims to make it the first “National Park City” while Paris is building four inner-city urban forests by 2020. While building heights provided a measure of a metropolis in the twentieth century, projects of urban greening have led to a search for more climate-tolerant trees–including “resilient” non-natives, like the three-toothed maple, even if urban planners are wary of invasive non-natives: Ireland’s commitment to plant 440 million trees by 2040, and hopes in Ethiopia to plant five billion seedlings in a year suggested a positive project of greening before the coronavirus pandemic, and an optimistic foot-forward re-engineering of the urban biome of unprecedented scale.

1. It was not always that way, and the spate of overbuilding in San Francisco has led it to aspire to a vertical landscape, as if out of envy of urban skylines of the east coast. If environmental dysphoria might be countered by planting of trees, San Francisco has gained a skyline of something like skyscrapers–as if in spite of its seismic risks–

–while the place of nature in the city in San Francisco, rather than on its outer bonds or beyond its walls, even before construction of a looming Salesforce Tower, we seek still to see as a site for outdoor recreation–

–if we may, as in a recent encomia to the city’s often beleaguered transit authority, bracket its impact as a building by reducing its size, and presence on our skyline, by continuing to render its towers as roughly equal to the TransAmerica Tower familiar as a point of reference that once dominated it in the past, as if its skyline remained roughly uniform.

The transformation of overpaving urban space has led to city maps that are more reliant on a strictly automobilistic perspective, as Google Maps and Bing are drawn from the perspectives of a space that is inhabited by cars, more tan the wildlife of the city: the perspective of the walker in the city is less easy to approach, in maps that are biased by their exclusion of open space that is so important to one’s mental health and sense of place: if the American West was once defined by its open spaces, “where the pavement ends,” the pavement that spreads out from cities to the burgeoning Bay Area makes it a sort of transportation hub, where cars move along its freeways and downtown, often clogging Market Street, increasing a market for new navigational tools of traffic flow, rather than the open spaces that drivers might even neglect if they did not also wander the neighborhoods off the beaten path: the decal of urban wildlife associated with the car’s perspective is, unsurprisingly, marked the pigeon as an urban inhabitant of peaking into this automobilistic world as if from an Archimedian point–

–whose cocked beaks and blank eyes emerge from the car door’s gleam to note the increased compromising of a biophilic relation to urban space.

And if we may still sense the city is present in nature, overlapping with bodies of water in ways one can still smell in its oxygenated ocean air, one want to map its relation to its environment, and find environments of living species that coexist in and with it, from raven nests or occasional hawks and odd coyote, or the pleasures of the butterfly, cormorant, and heron–that we too often fail to notice and to see, as if to cut off aspects of urban livability to create the environmental dysphoria we seek to avoid.

The sense of San Francisco as surrounded by the Pacific and freshwater basins, and a confluence of saltwater and freshwater, and a terrain whose sandiness and lack of bedrock has limited its urban growth. But the clear and unmistakable sense of being on the water, or lying close to it on three sides–defines a sense of what it is like to move in its micro-climates, and indeed the rewriting of its shores, while expanded by landfill, have resisted the possible dramatic change of an elevated freeway that bound its edges. If one can look back wistfully at the redefining of its relation to land and sea, there is a sense that even if some of the shorelines around the Embarcadero have clear breakfronts, and that undersea rivers, underground shipwrecks, and some bays are overpaved–

–that the older pre-1854 exists in the ocean air that enters its shores, if the coast is fixed. For if the low structures around the shoreline reflect in large part seismic risk, there is will to remain a model urban area, unique and exemplary even in an age of globalization and climate change, not entirely low-lying, but facing significant threats from sea-level rise. The overlapping of ocean and land environments are nicely captured in the species, from shorebirds to insects to thistle to prehistoric radiolarian, that populate the surface of San Francisco in the elegantly dynamic, if static, full-color map from Nature in the City, which presses web-sources and online data into a new illustrated paper form.

3. Fostering of a changed relation to urban habitat has left the Bay Area and city far less insularly defined in relation to nature than most other places in the United States: Rebecca Solnit rightly observed the old geographers were wrong only in one–if one significant–way in describing California as an island, which extends to San Francisco. In California, one finds, still, significant surviving greenspace, cultivable land, and open space, that while under threat, in proportion to much of the eastern seaboard extends to San Francisco and much of northern California, and significant parts of the southern coast. If the state is known for giant redwood forests and sequoia groves, strikingly significant habitats enter San Francisco’s own natural ecology in its urbanized space.

The recalibration of the place of nature to which San Francisco has been long open has long been measured as something that is threatened and endangered in its scarcity, as paving of asphalt and concrete have dramatically changed its landcover, toward a shift to appreciate and embrace its nature, and indeed embrace the benefits of cultivating not only plants, but rather ecophilia. The celebration of an urban environment far often reduced to being mapped for seismic peril and proximity to fault-lines offers a deep picture of the specific formation and sustainment of a rather unique coastal habitat, both based on accurate data and pushing the boundaries of data visualization to excavate a rich record of–and promote a wonderfully tactile relationship to–broad concerns of ecology and environmental history.

The engaging design of the 2018 map commissioned by Nature in the City begins from a datapoint of each and every tree and green space the city offers, but fosters a productive way of looking at the urban environment, different in that it focusses far less on the pests we often seek to eliminate from our homes with urban fastidiousness, than to appreciate the range of species beside which city dwellers live, despite their frequent focus on roads of paved concrete: in a map that embraces the city at the end of the peninsula from bay to sea, the living cornucopia of habitat that spans the urban environment offers a new way to understand this urban space.

Nature in the City/2018

Although ecosystems are the most living areas of cities, they remain hidden from view on city maps of the built landscape or paved roads that define the mobility of “urban” life.  

But we often fail to orient ourselves to the extent of urban environments in most maps–especially as we privilege the images of the city seen from the air, as if on landing and take-off, rather than on the ground. The changing vulnerability of cites to climate change and extreme weather has directed increased attention to the vulnerability and instability of urban space, in ways we are still taking stock through maps, the question of what maps best orient us to the future of the city have provoked increased attention from maps of sea-level change, to maps of vulnerability to earthquakes and seismic risks. No city has been more subject to such demands for recalibrating its lived space, perhaps, than San Francisco, the city that is most conspicuously built on several fault lines–so much that the expansive recent downtown rebuilding is cast as a “seismic trap” or a disasters waiting to happen–showing the spate of high-rise construction–

–against the backdrop of the widespread urban devastation of the 1906 earthquake on its hundred and twelfth anniversary, as if to suggest that the memory of that devastating event has receded into the past of public memory.

And if San Francisco was long haunted by the devastating downtown fire that spread through the city with the earthquake of 190 destroyed a good section of the inhabited city, as if it is burned into public memory. The recent shift in rebuilding of elevated buildings allowed to be constructed in the downtown region half almost reflexively prompted the worries or concern of a “seismic trap” in which recurrent seismic tremors threaten the city, and an incursion of nature of underground plate tectonics might even more consequentl disrupt the urban plant once again.

Are the danger of such seismic shocks a different image of the sudden entrance of nature into the city?

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Filed under data visualization, ecology, environmental geography, San Francisco, urban ecology

Mapping Fault-Lines in Earthquake Maps

Fracking–it is increasingly feared–invites irreparably contaminating our largest aquifers, and by extension drinking supplies–in Brooklyn, someone formed a group to protect the water of locally sourced beers–as well as devastate prairies and old agricultural lands, where land is cheap, by horizontal drilling.  Recent arguments compellingly link the drilling multiple “injection wells” of wastewater that seem to have activated previously non-active faults in regions that rarely experienced tremors in the past, and where the USGS did not find evidence of registered earthquakes.

As massive amounts of wastewater generated to access for natural gasses are forcefully re-injected into the earth, as if swept under a carpet, opening fissures in underlying beds of Shale or Sandstone.  Horizontal drilling operations have dated to 2008, mining areas by pumping vast amounts of sand into ancient shale formations in prairies and regions of declining agriculture to release methane and natural gasses.  Hydraulic fracking has used tons of water to force trapped gasses out of old rock formations.  Before 2009, in fact, earthquakes were rarely registered in the USGS surveys of lands where seismic activity has accompanied the injection of water into “injection wells”:  in these the shifting weight that the injected water that presses against rocks open old fissures, causing a buckling of underground rock formations, the fear is, as massive amounts of soupy, contaminated wastewater is injected back into the earth.  The “earthquake swarms” monitored nearby injection wells in Arkansas, Montana, Texas, Ohio or Oklahoma that barely registered seismic activity  from 1972 – 2008, has given new significance to–and created new fear around–a set of fault lines unknown to inhabitants, blamed as if active by an industry that rejects the accusations that they created sources for tremors inhabitants fear.   Indeed, the proliferation of earthquakes registered in the state of Oklahoma alone from 2001-15 reveals, according to the data from the Leonard Geophysical Observatory, a persistent increase in the tremor-like disturbances with the rise of underground wastewater dispersal, and a strikingly sharp increase in quakes of magnitude of three or higher in hears after 2010.

 

QUakes in OK, 2001-15.png

 

The increase seems closely tied to the absorption of wastewater back into rock layers whose weight is so altered by the injection of fluids, causing quakes that have rocked up to a fifth of the state, but have also increased land values for speculative fracking, in ways that may have concealed some interest in exploring the correlation–especially in a state where, due to geomorphological accident, water injected to reach deep-lying shale deposits send increasing amounts of wastewater underground, often to be absorbed by highly porous limestone that expands, but lies deep underground beside highly stressed layers of rock.  The result seems to create something like a combustive effect akin to the popping of kernels of corn, and has led many state officials to preemptively adopt prohibitions on local bans on regulating oil or gas wells in their jurisdictions, and insistence that the resurgence of quakes in fault zones is more able to be explained as an “act of nature that is nobody’s fault” not effected by human agency; the rejection of a relation to human activity comes from state legislatures fearful of the employment rises brought by gas and oil corporations from being scared away from the state.    But the geological record of apparently induced quakes in Oklahoma and their close proximity to existing injection wells.

 

ok.png

The fear of such tremors has a recent prehistory of three or so years.  An early tremor whose epicenter lay near Richmond, Virginia, of 5.8 magnitude, just below 6, but that sent shocks to North Carolina and Canada.  The event raised questions about the role of fracking in 2011 for Tim McDonnell and Aaron Ross, described in an earlier article in Mother Jones that directed attention to fracking’s consequences.  But the persuasive nature of recent USGS time-lapse maps of the same state–

The dangers of fracking echoes Jonathan Franzen’s early if compelling 1992 novel Strong Motion, in which mysteriously recurring earthquakes are pinpointed at the unlikely site of Boston, Massachusetts, a rare location of seismic activity.  But whereas Franzen’s protagonist, Renée Seitcheck, believed “that these earthquakes are the byproduct of industrial drilling” by a  petrochemical firm whose agents attempt to assassinate a beautiful rebel seismologist, for her mining of top-secret data from computers, the causes of the “swarms” seem to lie less in drilling than in injecting waste-water.  Was the novel remarkably prescient in unveiling a concealed impact of post-industrial geocaching?  It surely doesn’t seem so paranoid in its view of an industrial conspiracy to conceal geological findings, or to imagine the role of the rogue geographer in the seismically sensitive landscape that the search for underground sources of oil and gas can create.

But now it’s no longer isolated individuals who research the papers of top-secret labs.  There are upwards of 40,000 disposal wells actually active in the United States, some tunneling 13,000 feet under the earth, and “injection induced seismicity” is now a field, as the pressure exerted by the displacement of water able to move rock layers has provoked widespread academic interest and industrial concern:  “There are faults most everywhere,” noted Cliff Frohlich of the Institute for Geophysics at the University of Texas-Austin, suggesting how fracking can ‘reactivate’ fault lines which were never known; “Most of them are stuck, because rock on rock is pretty sticky.  But if you pump a fluid in there to reduce the friction, they can slip.”  “Water does not like to be squeezed,” Scott Ausbrooks of the Arkansas Geological Survey put it with some empathy.   And while Franzen’s character pored over reams of secret data to understand the relations of seismic activity to big oil’s search for underground pools of oil, such relations are now the focus of conferences and are amply documented in data maps.

The best known faults the USGS has mapped are well-known.  But, as Mark Zoback, a professor of geophysics at Stanford explained in a recent article by Michael Behar in Mother Jones, echoing Frohlich, “there are faults everywhere, and some are too small to be seen.”  Faults are widely known if often forgotten by those living in California, where fracking may begin, despite growing opposition.  Indeed the range of fault-lines throughout the California-Nevada region are so multiple that the possibility of hydraulic fracking in the region of southern California threatens to  imbalance a rather threatening constellation of seismic activity that already exists in much of the region, and is more widely mapped than the most familiar lines of the San Andreas, Calaveras, or Hayward faults.  The visibility of these fault-lines is available on an up-to-the-minute-map of regional seismic activity, part of a set of maps that record seismic activity by irregular bright red computer-generated lines, often proximate to cities:

California in USGS map of Faultlines

The nervously drawn red lines of seismic activity furrowing the green plains in these maps are ‘underground views’ mapping the range of pressure below the earth’s surface.  A more striking map of seismic activity of the past few weeks and days pieces together a narrative of fault-lines and tectonic plates that accentuate the daily deep divisions that course under the earth of our westernmost states:

California_Nevada-1

The stark legend suggests the huge growth in a magnitude the scale of “6.”  The prominent indexing of fault-lines in another USGS map of seismic activity, with less attention to topographic or climactic variation, shows the volatility of the region’s multiple faults in a similar if starker image of seismic frequency:

indexfault_map

 

More locally, and limited to faults active in the past week of a magnitude above 2.5,
California in USGS map of Faultlines

 

For more focus on recent seismic occurrence, link your browser to: http://earthquake.usgs.gov/earthquakes/map/

Despite the evidence of terrifyingly active fault lines, the active movement ‘Stop Fracking in California‘ has its back against the wall, even if they are growing in local Southern California chapters.

Yet the volatility of the region cannot be ignored–take this map of the Simi Valley and Los Angeles area, posted on Saturday, February 16, where fault-lines course unseen beneath the landscape, moving from inland to the coast at multiple points and through metropolitan Los Angeles:

Los Angeles earthquake faults

This interest to frack in California–an oddly post-modern verb–is scariest given maps approximating the future likelihood, as calculated by the USGS, that the regional fault-lines in the Bay Area will experience seismic activity at a magnitude greater than 6.7 before 2036.

2008probabilities-lrg

By how much would active injection wells multiply increase these already quite sizable odds?  Given the proximity of these lines to expanding urban areas, often growing between the Hayward and San Andreas fault, can fracking in California be a safe investment for the future?

This is not a map that is in the heads of most native Californians or residents.  The readability of these maps offers a base-line for future seismic activity, and grounds for concern about hydraulic fracking in seismically active regions.

It is good news that the USGS has expanded its clickable interactive image of global fault lines, in which the record of seismic activity is updated every minute, and on which viewers can scale in to investigate on their own:

USGS Global Earthquake Map

While the occurrence of faults and tremors will always shock, its legibility not only offers a lesson in continental drift.  Many of these jerky lines reminiscent of an etch-a-sketch lie underwater, but the points of greatest activity–in California, Indonesia, and Central America–cannot be ignored or lost sight of for underground engineers.

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Filed under data visualizations, Earthquake Probability, Earthquake swarms, earthquakes, Fracking