• This website includes dozens of videos, hundreds of essays, and thousands of drawings created over the past twenty years. Search to learn more about the history of buildings, places, prisons, Newark, New York City, and my PhD research on spatial inequality.

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Here Grows New York City

Music: “The Language of Cities” by Maserati

1. The Animation

Here Grows New York visually animates the development of this city’s street grid and environment from 1609 to the present day, using geo-referenced road network data, historic maps, and geological surveys. The resulting short film presents a series of “cartographic snapshots” of the built-up environment at intervals of every 20 to 30 years in history. This process highlights the organic spurts of growth and movement that typify New York’s and most cities’ development through time. The result is an abstract representation of urbanism.
Featured in:
– Laughing Squid   March 12, 2019
Viewing NYC   March 14
– silive.com   March 14
Open Culture   April 17
– Columbia Data Science Institute   May 1
– Library of Congress Blog   May 2
– Kottke.org   May 6
NYNJ.com   May 13
– 6sqft   May 13
– UK Daily Mail   August 28
– LangweileDich.net   June 11, 2020
– Wikipedia
New Amsterdam History Center   December 1, 2020
Bunk History   July 2021
– Camden Town, 2023 textbook by Westermann Group
– Inspired by Cambridge University’s London Evolution Animation and this map of Barcelona

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2. The Interactive Map

The results of this animation are transformed into this fully interactive map

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3. Research Method

Several hundred maps in the digital archives of the New York Public Library and Library of Congress were analyzed to assemble this film. About 25 of these maps were then selected, downloaded, merged, stretched, and warped in a single document to align with each other. This provided a consistent scale and allowed easier comparison of differences between maps of different date. As the source files were all in different colors, scales, and designs, we created a single base map with unified graphics. The redrawing not only permits correcting errors in less accurate old maps but also provides a graphic representation that is consistent over time. This coherence allows the rate and trends in urban growth to be read more easily and compared between eras.
Click here to read the research methodology and list of maps consulted.
Or watch the video tutorial below of the workflow and software behind the animation

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4. Conclusions and Analysis

This data visualization informs our analysis of the history of the New York City grid. This analysis reflects on the question: What can the built environment of Manhattan’s streets reflect about the evolving social and economic priorities of city planners and leaders? The long phases of urban growth and shifting transportation modes created distinctive road networks in Manhattan. The predominance of different forms of transport during each era also prompted changes to the location and dimensions of streets in response. Manhattan illustrates the evolution of these road networks over four centuries of near continuous growth. A plot can describe a street grid, as well as its builders’ story. This paper aims to tell this second plot, a story of urbanism.
Click here to read the conclusions as part of a working paper
written with Professor Kenneth T. Jackson.

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5. Credits and Appendix

This project would not have been possible without the support, mentorship, and patience of my parents, Anne Mabry and Zemin Zemin Zhang. Nor would this project have been possible without the historical expertise of Columbia University professors Kenneth T. Jackson (History Department) and Gergely Baics (Urban Studies). Thanks is also extended to those who reviewed and critiqued this project in its early stages, including Chris Kok, Wright Kennedy, Dan Miller, and the Center for Spatial Research at Columbia’s Department of History. Most importantly, I thank my dog ChoiChoi.

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Anyone may reuse or republish this content, so long as credit is provided with the link back to this page. If you email [email protected], I will gladly send along the graphics, maps, and source files associated.

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Architecture of Exclusion in Manhattan Chinatown

Originally published in the 2018-19 edition of the Asia Pacific Affairs Council journal with help from Seeun Yim at Columbia University’s Weatherhead East Asian Institute, pages 18-20

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Canal and Mott Street

In 1882, the Chinese Exclusion Act restricted Chinese immigration to the US, prohibited Chinese females from immigrating on grounds of “prostitution,” and revoked the citizenship of any US citizen who married a Chinese male. The consequences of this xenophobic legislation motivated Chinese immigrants to flee racial violence in the American West and to settle in Manhattan’s Chinatown. With a population now of around fifty thousand (2010 census), this remains the largest ethnically Chinese enclave in the Western Hemisphere.

Barbershop Row on Doyers Street

Thanks to New York’s geographic location as a port city with high industrial employment and easy connections to the American interior, this city became the primary point of entry for waves of immigrant groups in the nineteenth century: Irish, Germans, Italians, and Eastern Europeans. What makes the Chinese different, though, is the survival and resilience of the immigrant community they created. Other immigrant groups – namely the Germans and Irish – converged around large neighborhoods and surrounded themselves with familiar languages and businesses. Of these enclaves, all have since disappeared. The children of these first-generation immigrants successfully assimilated into American society, earned higher incomes than their parents, and therefore chose to disperse to non-immigrant neighborhoods with better housing stock and schools. Yet, the Chinese remained.
The resilience of this community results from a confluence of factors: cultural, geographic, and political. Of innumerable immigrant groups to the US, the Chinese were among the only to have the most restrictive laws placed on their immigration. This stigma drove them toward three types of low-paid labor – with which white Americans still deeply associate with the Chinese – laundries, restaurants, and garment manufacturing. Like the Chinese, other groups – particularly Irish-immigrant females – began working in these professions, but they soon climbed the social ladder.

Mosco Street and Mulberry Bend

As an architectural historian, I see that the political and racial agenda of exclusion is imprinted in the built environment of Chinatown. To present this neighborhood’s geography: For most of its history, Chinatown was bordered to the north by Canal Street, to the east by Bowery, and to the South and West by the city’s federal courthouse and jail. The center of this community lies on the low wetland above a filled-in and polluted lake called the Collect Pond. Historically, this area contained the city’s worst housing stock, was home to the city’s first tenement building (65 Mott Street), and was the epicenter for waterborne cholera during the epidemics of 1832 (~3,000 deaths) and again in 1866 (1,137 deaths). The city’s first slum clearance project was also in Chinatown to create what is now present-day Columbus Park.
Race-based policies of exclusion can take different forms in the built-environment. The quality of street cleaning and the frequency of street closures are a place to start. Some of the city’s dirtiest sidewalks and streets are consistently located within Chinatown – as well as some of the most crowded with street vendors, particularly Mulberry and Mott Street). Yet, as these streets continue northward above Canal Street, their character changes. The street sections immediately north in the enclave of Little Italy are frequently cleaned and closed for traffic most of the year to create a car-free pedestrian mall bordered by upscale Italian restaurants for tourists. The sections of Mulberry Street in Chinatown are always open to traffic and truck deliveries.

Grocery Store at Bayard and Mulberry Streets

Unequal treatment continues when examining the proximity of Chinatown to centers of political power and criminal justice. Since 1838, the city’s central prison (named the Tombs because of its foreboding appearance and damp interior) was located just adjacent to Chinatown. The Fifth Police Precinct is also located at the center of this community at 19 Elizabeth Street. Although Chinatown was ranked 58th safest out of the city’s 69 patrol areas and has a crime rate well below the city average, the incarceration rate of 449 inmates per 100,000 people is slightly higher than the city average of 443 per 100,000. This incarceration rate is also significantly higher than adjacent neighborhoods like SoHo that have a rate well below 100 per 100,000. NYC Open Data reveals this neighborhood to be targeted for certain – perhaps race-specific and generally non-violent crimes – like gambling and forgery. Over half of all NYPD arrests related to gambling are in Manhattan Chinatown. Similarly, the only financial institution to face criminal charges after the 2008 financial crisis was Chinatown’s family-owned Abacus Federal Savings Bank – on allegations of mortgage fraud later found false in court by a 12-0 jury decision in favor of Abacus. Abacus provided mortgages and unconventional financial services to the kinds of immigrants traditionally locked out of the banking system, and therefore denied the means to climb the social ladder. The mistreatment of the Chinese in America both past and present is part of a larger anti-China agenda.
When it comes to tourism, Americans seem to have a paradoxical relationship with Chinatown’s “oriental” culture and cuisine. On the one hand, there is a proclaimed love of East Asian cuisine and art, as evidenced by the profusion of Asian-themed restaurants for tourists, or as evidenced by the phenomenon in art history for western artists (and particularly French Impressionists) to incorporate decorative motifs from East Asian woodcuts and ceramics into their work. On the other hand, there is simultaneously exclusion of the people who created this Chinese food and art from political power and social mobility. Still today, Americans seem to want competitively priced Chinese products without suffering the presence of the foreigners who produced these products.

Forsyth and Delancey Street

Let us clarify one thing: The division in Chinatown is not “apartheid” in the strict sense. It is perhaps a division more subtle and difficult to notice. It expresses the kind of unequal treatment – antiquated housing, crowded conditions, and municipal apathy – that face many immigrant groups in America. The built environment of Chinatown is something altogether more complicated and layered with other ethnic groups, too. For instance, the Church of the Transfiguration in the center of Chinatown now has a majority Asian congregation, even though it was founded in 1815 as a German and Lutheran church. Similarly, some of the funeral parlors on Mulberry Bend have Italian origins and old Italian men in the funeral bands.  This neighborhood is also in the active process of gentrification with rising rents pushing out older Asian businesses.
If and when the Chinese become fully integrated into American society, how should the architectural fabric of this immigrant enclave be preserved, considering that its very existence is a marker of race-based exclusion and the century-long challenge of the Chinese in America?

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This time-lapse of Manhattan Chinatown took sixty hours to complete and measures 26 by 40 inches. Chinatown’s tenements are in the foreground, while the skyscraper canyons of Lower Manhattan rise on top. This shows the area of Chinatown bordered by Bowery, Canal Street, and Columbus Park.

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Chinese music: Feng Yang (The Flower Drum)

Geography of Marijuana Arrests

Update March 2021: Marijuana is now legal in NY state.

 

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The New York Police Department (NYPD) made 102,992 arrests in 2017 for the possession, sale, and/or use of marijuana. 1 While only 25.5% of New Yorkers are Black, 67.5% of marijuana arrests are of Blacks. Similarly, 90% marijuana arrests are male, even though only 65% marijuana users are male. 2 Males more than females and Blacks more than others are arrested for marijuana in disproportionate numbers.

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Race
Percentage of New Yorkers who identify as this race 3
Percentage of marijuana arrests of individuals belonging to this race
White
44.0%
11.2%
Black
25.5%
67.5%
Asian/Pacific Islander
12.8%
4.2%
Other
17.7%
17.1%

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2017 data

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Click table to view in detail

NYPD marijuana arrests are disproportionately of Black males between the ages of 18 and 44 from low-income communities, even though this demographic represents less than 10% of the city’s population. Why should this matter? Arresting individuals for using a relatively harmless and non-addictive drug is expensive for taxpayers. According to the Drug Policy Alliance, the city spends $75 million on marijuana arrests and prosecution per year. 4 This is money that could have gone to education, parks, and community programs. Marijuana policy targets our country’s poorest people of color.
The common argument, and the grounds on which marijuana was initially made illegal, is that marijuana is a “gateway drug.” Marijuana supposedly introduces and later encourages individuals to experiment with more dangerous and addictive substances. Whether or not this is true, the arrest and punishment of individuals for marijuana may incur the equal risk of becoming a “gateway crime” to the legal system. With a prison record from a marijuana arrest, a person of color may have more difficulty finding employment and re-entering society – ironically pushing them to desperation and possibly new and greater crimes than their initial arrest.

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View this pie chart in more detail.

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Below are three maps of neighborhood “hotspots” for marijuana arrests. The income of every block is indicated on a red to green color scale from low to high income. The population of Latinos and Blacks per square mile is also indicated; unsurprisingly, these groups cluster in low-income neighborhoods. On this base map is the geo-referenced address of every arrest for marijuana possession or sale from 2013 to 2017.
Marijuana arrests tend to happen in low-income neighborhoods. For instance, Manhattan’s 96th Street represents an income divide between the wealthy Upper East Side and the comparatively poorer Harlem. Drawing a “thin blue line” down 96th Street, we also identify an unspoken policing boundary. Marijuana arrests are significantly less likely to happen in the majority-White neighborhood south of 96th than in the majority-Black neighborhood north, even though both neighborhoods are of comparable population density and likely comparable rates of marijuana use. According to the UCLA: “Despite roughly equal usage rates, Blacks are 3.73 times more likely than Whites to be arrested for marijuana.” 5 Similarly, the wealthy and majority-White neighborhood of Riverdale in the Bronx has few arrests in comparison to the poorer and majority-Black West Bronx, even though these two neighborhoods are less than mile apart.

 

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Research Method

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Note that on the above map, there are numerous low-income neighborhoods without any drug arrests. This is largely because these areas have little to no population, such as Central Park or LaGuardia Airport. Controlling for population density, marijuana arrests still target communities of color.
This project was assembled from public data. I downloaded anonymized microdata on the race, crime, gender, and approximate age of every individual arrested by NYPD, as well as the address where this individual was arrested. Of the approximately 1.7 million arrests in this data set, I filtered out the marijuana crimes. The colored basemap indicating per capita income and race by city block is extracted from Tableau Public, the mapping software I use. The infographics presented above can be explored or downloaded here. Arrest data is from NYC Open Data here.

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Endnotes

  1. Marijuana arrests represent 5.98% of all NYPD arrests in 2017.
  2. From “Statista,” accessed 15 January 2019, link.
  3. From the United States Census Bureau, 2010 statistics on NYC demographics, link to report, link to database.
  4. From the Drug Policy Alliance, accessed 15 January 2019, link to press release, link to report.
  5. From the American Civil Liberties Union, accessed 18 January 2019, link to article.

A History of Historic Preservation in New York City

Data analysis of NYC landmarks since 1965 reveals trends and biases in the landmarks preservation movement.

Developed with urban historian Kenneth Jackson at Columbia University’s Department of History

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A visual history of landmarks preservation in NYC. Data from NYC Open Data. Music from Freesound.

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Introduction

There is ongoing debate between in NYC between developers seeking to rebuild the city in the image of global capitalism and preservationists seeking to slow the rate of change and protect the appearance of the city’s many and distinct neighborhoods. Several factors drive historic preservation: fear of losing heritage; fear of change; historians, public servants, and well-intentioned activists in the spirit of Jane Jacobs. This debate has played out every year since 1965 through the hundreds of structures that are added to (or rejected from) the Landmarks Preservation Commission’s running list of landmarks (LPC). Once added, landmarked buildings cannot be modified without first seeking approval from the city. Landmarks preservation is contentious for developers because the protections of preservation law are permanent and affect all current and future owners. Preservation law further restricts significant rebuilding, even if demolition and rebuilding are lucrative for the property owner.
Historians decide the future of the city’s built environment. The sites they preserve will become the architectural lens through which future generations will appreciate the past. The sites they approve for demolition will be lost to history. Preservation is a response to larger historical questions: Which aspects of the past are worth preserving? How should the city balance the economic need for development with the cultural need for history?
This paper will assess the landscape of historic preservation through analysis of publicly-available landmark records from NYC Open Data. We identified two datasets, both containing ~130,000 spreadsheet entries for every single LPC listing from 1965 to 2019. The first dataset is titled “Individual Landmarks” 1 and includes the structure’s address, lot-size, and date landmarked. The second dataset is titled “LPC Individual Landmark and Historic District Building Database” 2  and includes the construction date, original use, style, and address of all structures. We downloaded both datasets as .csv files, imported them into a visualization software called Tableau, merged them into a single map, and then analyzed the data. The results of inform the conclusions presented here. This analysis is broken into four case studies:
  1. Distribution of Landmarks over the Five Boroughs
    Assesses where landmarks preservation is densest or least dense by neighborhood.
  2. Contextual Preservation?
    Analyzes how protecting a landmark limits redevelopment of neighboring properties of less aesthetic value
  3. How does the preservation movement reflect economic patterns?
    – Factor affecting the preservation of city-owned structures
    – Factors affecting the preservation of residential structures
    – Relationship between preservation and gentrification?
  4. Keeping up to pace?
    Questions the degree to which landmarks preservation succeeds in protecting recently-built landmarks
From this data, hidden trends and biases in historic preservation become visible. Firstly, we identify a higher-density of landmarks in certain (and usually higher income) neighborhoods. Secondly, we identify a marked preference among historians for protecting structures pre-1945. (Is there so little in the city’s recent architectural history that is worth preserving?) And thirdly, our analysis hints at the strength of market forces and developers in shaping the scope and definition of preservation.

Read More

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  1. “Individual Landmarks,” NYC Open Data, https://data.cityofnewyork.us/Housing-Development/Individual-Landmarks/ch5p-r223 (retrieved 5 November 2018).
  2. “LPC Individual Landmark and Historic District Building Database” NYC Open Data, https://data.cityofnewyork.us/Housing-Development/LPC-Individual-Landmark-and-Historic-District-Buil/7mgd-s57w (retrieved 5 November 2018).

A Brief History of Mulberry Bend

At the intersection of history and the immigrant experience

Written for Kenneth Jackson’s Columbia University undergraduate course “History of the City of New York”

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Mulberry Bend c.1896. Buildings on left side of street are now demolished.[1]

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Mulberry Bend, nestled between the New York County Criminal Court and the tenements of Chinatown, is at the geographic crossroads of New York City history. At 500 feet long and 50 feet wide, Mulberry Bend is between Bayard Street to the north and Worth Street to the south. Named after the slight turn the street makes midblock, the Bend has a rich, over 350 year history: marsh, city slum, site of urban renewal, and now heart of the Western Hemisphere’s largest Chinese enclave.[2] Through its rich history, the Bend’s brick and wood-frame tenements hosted waves of immigrant groups: Irish, Italians, freed blacks, and now the Chinese, one of New York’s most resilient immigrant groups whose presence in Chinatown reaches as far back as the 1830s. Consistent to these immigrant groups is their struggle to survive and prosper in America. Many of these immigrants, such as the Irish and Italians, have long left the Five Points neighborhood where the Bend is located, leaving few traces of their presence. But the neighborhood was vital as their first point of contact in the New World, a way station between their country of origin and future prosperity in the Promised Land. As such, the Bend exemplifies some of the trademarks of the immigrant experience: a working-class community populated by an immigrant diaspora that emulates the language and tradition of their country of birth. Though their homeland may be distant, in Italy, Spain, Germany, Ireland, or China, they recreated a familiar world beneath the skyscrapers of Lower Manhattan. Neither fully American nor fully foreign, neither a quiet residential street nor busy commercial thoroughfare, the Bend existed and exists as a community of transient identity.
When the Dutch first settled New York, the area of Mulberry Bend and Chinatown was wooded and marshy land. The Bowery, one block east of what would become Mulberry Bend, was a Lenape Indian trail traveling from the tip of Manhattan to the heights of Harlem, about ten miles distant. The New York County Criminal Courts, one block west of the Bend, was the site of colonial New York’s main source of drinking water, the Collect Pond.[3] Change came when the city’s tanning industry developed at the adjoining Collect Pond because it could carry away their industrial waste. The Ratzer Map of Manhattan, dated 1776, even plots the Bend, which bends to avoid the marshy topography of the Collect Pond. Despite this moderate industrial development and gradual filling in of the pond with soil, the area remained marshy and unfit for living.[4]

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Excerpt from the 1776 Ratzer Map of Lower Manhattan. The area labeled as “Common” is now City Hall Park, the “Fresh Water” body was known as Collect Pond, and the “Tanners Yards” was the center of the future Five Points Slum. Mulberry Bend is the line in bright red. The dotted land pattern indicated low-lying marshes and woods that have yet to be developed. The grid of streets had been laid out, but had yet to be populated with tenements and businesses.[5]

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Love and Longing in New York

Selected from undergraduate college application essay to Columbia University. Read more.

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Walking is my form of enlightenment.
I live in Newark.  My city is generally ten degrees hotter than its neighboring environment.  The airport.  The port.  The downtown.  All are blanketed in asphalt that turns my city into a hot desert.
Tens of thousands of cars, and one of the largest garbage incinerators in the country, spew their fumes into my city.  Returning home, the smell of burning garbage often greets me.  As a child, I had asthma.
At night, I am alone.  Nobody my age lives in my neighborhood. From my front window, I see a parking lot for corporate commuters. From my back window, I see a vast parking lot for university students.  Both are desolate after dusk. As an infant, my first words were “demolition” and “truck.”  As a child, I never had play dates; my suburban “friends” feared my city.  As an adult, I hope to see my city’s vacant lots developed.  I keep on dreaming.
The streets of my city are not made for walking.  They are made for driving.  I walk.  I stop.  I wait.  Speeding traffic and interminable stoplights hinder my progress.
But I love walking in New York City.
When I walk, I am free to choose.  Each street guides me forward.  Each intersection is a choice.  Each destination is irrelevant.  When I walk, I sometimes choose a random order of directions, left, right, left, right, right, left, left, straight.  I see where they lead me.  I know not where.
When I walk, I am free to move.  I love walking on the High Line.  I float above the cars that prevent the city from realizing itself as a community.  I see the crowded streets twenty feet below.  I see the gardens on either side of me.  I let the verdantly landscaped path channel me forward.
When I walk, I am no longer alone.  I walk in the footsteps of the millions who passed before me.  I am one among millions, all of us on our separate voyages.  Lawyers.  Butchers.  Tourists.  Homeless.  We all walk alone.  Yet, we are together in walking alone.
When I walk, I see the world.  In Spanish Harlem, street fairs sell traditional Mexican foods.  In college town Columbia, well-dressed university students amble on their way to class.  In the Upper West Side, the shabby chic push their grocery prams.  In Times Square, tourists lug their large shopping bags from theater to theater, store to store.  Finally, after many neighborhoods, I reach the ceaseless bustle of Wall Street.  Tired after many miles of walking, I descend the subway steps.
When I walk, I achieve tranquility. I am happy.
One of my recent projects is painting New York City, neighborhood by neighborhood.  Each day, I choose a new district to stroll through.  Then, equipped with my miniature watercolor palette and notepad, I walk and paint.  I discover the city block by block.  I aim to capture a fragment of what I see through painting.
Like a pianist who memorizes music by heart, the flâneur (or urban pedestrian) embraces the street symphony with his soul and feet.  People’s voices and buildings serve different, but equally important, clefs in the symphony.  As le Corbusier wrote, “… first to look, and then to observe, and finally to discover.”  My countless urban walks enhance my passion for cities, their architecture, their history, and their planning.
Living in Newark inspires me to dream.  Walking in New York City enlightens me to walk.  I am ready to walk my next journey.

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