November 2017

Everything In A City Is Manmade – Even The Water

by Don Friedman on November 30, 2017


Continuing with yesterday’s theme…

New York is located on two medium-sized islands (Manhattan and Staten Island), a portion of a large island (Brooklyn and Queens are the west end of Long Island), a piece of mainland (the Bronx) and a whole bunch of small islands in the surrounding waterways. Those waterways include small streams (e.g., the Bronx River) but also the East River (a tidal strait connecting the harbor and the Long Island Sound) and the Hudson River estuary. The East River is rather violent as rivers in the middle of cities go: because it’s actually not a river, its direction changes with each ┬áthe turn of the tide and the current speed regularly exceeds five miles per hour. The right-angle bend in the River near 125th Street in Manhattan, which is also the location of Ward’s Island, Randall’s Island, and the connection to the Harlem River (another tidal strait) is particularly dangerous and earned the name Hell Gate through numerous shipwrecks.

This has all been changed in different ways. The banks of the rivers have been straightened and moved with landfill, as well as being converted from sloping banks to hard bulkhead walls. Portions of the rivers have been considerably narrowed, which of course changes their flow. Piers create stagnant pockets along their edges. The dumping of raw sewage and other garbage changed their ecosystems; cleaning up the sewage has changed it again. The salt marsh south of Flushing Bay was changed to a garbage dump and then Flushing Meadows Park. Landfill turned a sand bar in the East River into Orchard Beach. Landfill turned Coney Island and Barren Island into peninsulas.

The pictures above (click to expand) show one of the more spectacular moments in this process. Flood Rock was one of the small semi-submerged islands and reefs that made Hell Gate so difficult for sailing shops to navigate. On October 10, 1885, it was dynamited to clear that portion of the channel. Each individual change to the East River was relatively small, but the overall effect has left in a state as artificial as Prospect Park: the water flowing through is from the Atlantic Ocean and the currents flow with the tides, but the channel containing the water has been modified by people for some 400 years.

Everything In A City Is Manmade

November 29, 2017

Another great article from Karrie Jacobs, this one on Prospect Park: here. I’m not even going to attempt to summarize it. You should read it because it’s a fascinating look at how parks in New York have developed over the last 150 years. Jacobs’s painstaking descriptions of the work that went into the creation of […]

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Just Like Us

November 28, 2017

A theme I tend to return to again and again is that people in the past acted the same way we do. They used the tools they had, worried about cost, sometimes had great ideas, sometime made dumb mistakes. They looked for ways to do things cheaper and easier, like we do, and that sometimes […]

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The Meaning of Failure

November 27, 2017

Trigger warning: The blog post below includes discussion of death in building failures. Definitions of structural engineering tend to be positive, as they should be. Safely and economically designing structures…that sort of thing. Engineers are, amazingly enough, human and prefer to think about success rather than failures. I’ve been working on a paper for the […]

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Schematic Design

November 26, 2017

More mining of the NYPL’s digital archive…this one is from an article in Progressive Architecture on the Chrysler Building, showing the evolution of the spire/dome in early design. There are changes up and down the building, but the most dramatic ones are at the top. Had the first design on the far left been built, […]

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An Early Stage

November 25, 2017

I hadn’t seen this picture before. That’s the Woolworth Building under construction, looking northwest from the east side of Broadway, near Ann Street. The ornate building on the right is the old General Post Office. The low buildings on the left were part of the Astor Hotel and were replaced in the 1920s by the […]

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Another Old Joke

November 24, 2017

Level, flush, or plumb: pick one. In this case the designer and the bench operator disagreed as to which was important.

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Happy Thanksgiving

November 23, 2017
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Relating Damage To Structural Type

November 22, 2017

Some stereoscopic views of Chicago after the 1871 fire: That’s the kind of devastation that a firestorm can cause. But it’s worth noting that different types of building fail differently. Nearly every building in Chicago before the fire was either of wood-stud construction (private houses and small commercial buildings) or of masonry walls with wood […]

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Temporary Until It’s Not

November 21, 2017

That’s the underside of a highway overpass. It’s old enough that the built-up plate girders that are the main structural elements are riveted together rather than being bolted or welded. The concrete deck looks very new and is a replacement. Since water and (in the past) road salt attack this structure from the driving surface […]

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