[Talk-us] [Talk-us-newyork] LAST CALL: Looking to start on reconciling New York City admin boundaries

[Kevin Kenny]

On Tue, May 31, 2022 at 10:10 PM <isstatenisland at tutanota.com> wrote:

> I agree, coastlines should not be merged with political boundaries. In
> this case the political boundaries are based on the coastline in
> nineteen-hundred whatever, pre-GPS. Coastline in OSM should refer to where
> the coast actually is and political boundaries should not move.
>
> Also, I see the Marble Hill boundary is wrong. The Manhattan-Bronx
> boundary should run in the bottom of the hill (former path of the river)
> and through several buildings.
>
> Maybe the tax map data is of some help?
>
> https://data.cityofnewyork.us/Housing-Development/Department-of-Finance-Digital-Tax-Map/smk3-tmxj
>
> Taking a second look... the data there also has problems. Some water areas
> belong to two lots in two different boroughs.
>
> I'm not convinced New York City even knows its exact borough boundaries.
> (Just look at Ellis Island: New York City's tax lot extends over portions
> of New Jersey's part of the island and waters. Other Hudson River lots also
> spill into the NJ side of the river)
>

The current political boundaries for New York City, excepting the midriver
boundary dispute with NJ, were fixed in 1898 with the Great Consolidation.
(I know some of that history because the community I grew up in petitioned,
successfully, to move from Town of Jamaica to Town of Hempstead so as to be
excluded from New York City, giving the newly-formed Nassau County a short
stretch of the shoreline of Jamaica Bay. With that partition was born one
of the most spectacular eras of machine politics that the US has seen:
http://societyessays.blogspot.com/2007/10/blog-post.html.)

Even pre-GPS, the coast survey was damned accurate! First-order control
points were expected to agree with the network with a standard deviation of
less than 10**-5 of the separation of the points.  (Controls 10 km apart
would have their distance measured to a tolerance of 10 cm.) I have no
trouble with scaling old topos - the error introduced by the paper swelling
and shrinking from variations in temperature and humidity is normally
greater than the survey error.

You're right that NYC never updated the tax maps for the settlement of the
boundary that partitioned Ellis Island and slightly shifted the nominal
NY-NJ boundary midriver. The change is pretty irrelevant to the taxing
authorities, because Uncle Sam is the landowner of all the affected land
area, and there's an interstate compact (the one that created the Port
Authority) that governs the river.

The lines between the boroughs are wrong in OSM because I haven't repaired
them yet!

The proposed line through Marble Hill is the heavy line on the map at
https://kbk.is-a-geek.net/attachments/20220601/marblehill.png.
OSM's current line for the county, as you can see, follows Johnson Avenue,
Irwin Avenue, West 230 Street and Exterior Street.  The current OSM line
for the borough is a few metres offshore from the present northern tip of
Manhattan Island in the relocated Spuyten Duyvil.  Both are wrong. The plan
is to conform both the borough line and the county line to the heavy line
on the map.  I'm not going to touch the community board boundaries.  I know
that Marble Hill, despite being in New York County, is Bronx Community
Board 8.

New York State and New York City both agree on the line around Marble Hill
accurately enough for 1:25000 scale rendering. I'm not going to fuss over
finer differences than that.


-- 
73 de ke9tv/2, Kevin
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/talk-us/attachments/20220601/3d4771d7/attachment.htm>