28 votes

Determining which US zipcodes map to more than one state or more than one city?

There are 13 multi-state US Census' ZIP Code Tabulation Areas (ZCTAs): 02861, 42223, 59221, 63673, 71749, 73949, 81137, 84536, 86044, 86515, 88063, 89439 & 97635. As others have mentioned, there ...
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25 votes

Which projection is best for mapping the contiguous United States?

The Albers equal area conic is the typical projection for historical USGS maps of the lower 48, it being a general-purpose low-distortion compromise for mid-latitude short and wide extents. As a ...
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  • 1,841
21 votes
Accepted

Are there duplicate Zip codes in the US?

There are no duplicate ZIP Codes. There are some ZIP Codes that are multi-part polygons, but those polygons are usually adjacent. Source: I manage/update ZIP Codes for the USPS
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  • 6,876
19 votes
Accepted

Does transforming to a new projection, then back, affect data accuracy?

I don't know which projection engine ArcGis uses, but a very interesting question also for proj.4. So I give it a try to test the proj.4 projection engine within the GNU-R environment. I use the NAD ...
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  • 3,463
17 votes
Accepted

What is the source of horizontal and vertical striping in USGS DEMs?

Attempt to answer my own question: The cause of striping in the examples I provided are entirely due to my workflow, not any legacy issue with how the data was originally assembled or mosaiced ...
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  • 2,010
16 votes

Choosing projected coordinate system for mapping all US states?

There are some free applications that let you try and play with projections. like: flexprojector They also indicate to what extend they preserve size, shape or direction. Depending on you ...
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  • 1,589
16 votes

Which projection is best for mapping the contiguous United States?

ESRI has defined three projections especially for the contiguos United states. These are included in QGIS as well: EPSG:102003 USA_Contiguous_Albers_Equal_Area_Conic +proj=aea +lat_1=29.5 +lat_2=45.5 ...
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  • 75.1k
15 votes
Accepted

Why is there no state with code "03" (among other missing numbers)?

These are Federal Information Processing Standard (FIPS) state codes, and the ones you mention are missing because, from the wiki: "certain numeric codes "are reserved for possible future use in ...
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  • 2,421
14 votes

Obtaining up-to-date list of US ZIP Codes with Latitude and Longitude Geocodes?

Try this: http://download.geonames.org/export/zip/ It is licensed under a Creative Commons Attribution 3.0 License. They even have zip codes of various other countries around the world.
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  • 141
12 votes
Accepted

Meaning of dash in house address number in USA?

In my experience, it usually means what you think it means: a range of address numbers. I've also seen it used as a way of writing an apartment or suite number, so 136-39 37 AVE would be 136 37th Ave, ...
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  • 12k
11 votes

Finding footprint data for US buildings?

Microsoft just open sourced 124,885,597 million computer generated building footprints in all 50 US states https://github.com/Microsoft/USBuildingFootprints
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10 votes

Seeking shapefile of city boundaries in US?

Getting the Data You can acquire US Census Place Data, which includes cities, here. For instance, Rhode Island's 2017 Place Data is available here. For ease of bulk downloading, the full list 2017 ...
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  • 1,761
10 votes
Accepted

What is Google source for United States topographic data?

There is more than one source depending on the area of interest around the globe. Google Maps is the terrain layer, which provides a shaded relief (aka hillshade) view of the topography derived ...
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  • 48.6k
9 votes
Accepted

What coordinate NOTATION would this be?

My guess is that 0558253.7 13083091W translates to 055.82537°N 130.83091°W which are decimal degrees lat and long, or 55° 49' 31.3" N and 130° 49' 51.3" W in deg-min-sec, located ...
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  • 8,604
8 votes

Getting a list of zip codes with its adjacent zip codes

Get a zip-code boundary layer and run Polygon Neighbors. Review How Polygon Neighbors Works and Up-To-Date Zip-Code Boundaries Picture below might be different than your ArcMap looks, but the buttons ...
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  • 3,043
8 votes
Accepted

Now that NationalAtlas.Gov is retired/removed, where is the largest source of public shapefiles for the USA?

I just checked my old National Atlas bookmark and was redirected not to the National Map Viewer, but to the National Map's Small Scale data page. There are 197 datasets available for download there, ...
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  • 12k
8 votes
Accepted

Displaying data from two UTM zones on one map?

I worked on updating some USGS quads, back in the 90s. It seemed like most of the style guidelines were published internally, long before the Internet, and never made it online. It's fairly common ...
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8 votes
Accepted

Identify this state outline file

It looks like it could be from the Project Linework website. Specifically, the "Angular" or "Twenty Seventy" datasets.
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  • 1,933
7 votes

Seeking sources for US Zip Code Boundaries

You can download shape files for 2019 Zip Code Tabulation Areas at no cost from https://www.census.gov/cgi-bin/geo/shapefiles/index.php?year=2019&layergroup=ZIP+Code+Tabulation+Areas However, ...
7 votes
Accepted

Does the NED use geocentric or geodetic latitude?

One could use either kind of latitude to locate points on the WGS 84 ellipsoid (used by the NED) or any other ellipsoid, but "everybody knows" that the values will always be given as ...
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  • 67.6k
7 votes

CRS for submission to Minnesota DOT

I bet it may be the slight discrepancy between Esri's WKT definition of 26915 and the OGC WKT version. I think the only real difference is in the name (NAD83 / UTM zone 15N vs NAD_1983_UTM_Zone_15N). ...
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7 votes

US / Mexican border data

You can obtain the line shapefile for the Mexican border from the U.S. Geological Survey website (or click here directly). Scroll down and from the list of Categories, select the Boundaries option. ...
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  • 72.4k
7 votes

Does transforming to a new projection, then back, affect data accuracy?

Esri has its own projection engine. Most projections and geographic/datum transformations methods are well-behaved when used in an appropriate area of interest. If you get too far outside of a UTM ...
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  • 18.2k
6 votes

Seeking 2010 Census Block data

They are available on the Census FTP site at http://www2.census.gov/geo/tiger/TIGER2010BLKPOPHU/
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  • 179
6 votes

Determining which US zipcodes map to more than one state or more than one city?

2016 TIGER Data with PostGIS As a special caveat, ZCTA data isn't USPS Zip Codes. It's an approximation of it. USPS Zip Codes are really horrible and not useful except to approximate. Everyone, ...
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  • 6,701
6 votes

Proj4 String for NAD83(2011) / Louisiana South (ftUS)

PROJ.4 strings always want the false easting (x_0) and false northing (y_0) in meters, no matter what the coordinate reference system units are. Change +x_0 to 1000000.0 and you should get the results ...
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  • 18.2k
6 votes
Accepted

Proj4 String for NAD83(2011) / Louisiana South (ftUS)

As as there is no support EPSG:6479 (NAD83(2011) / Louisiana South (ftUS)) in PROJ4 (look at the comment of mkennedy) I will illustrate the problem with EPSG:3452, NAD83 / Louisiana South (ftUS) ...
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  • 51.2k
6 votes
Accepted

What level of error expected when using NAD StatePlane CRS from adjacent state?

The northern two-thirds of Georgia should be pretty good, because the South Carolina coordinate reference system is Lambert conformal conic-based. Thus, the standard parallels extend through Georgia ...
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  • 18.2k
6 votes

Downloading US Census data?

American Fact Finder data (tabular) needs to be joined to TIGER data. The TIGER data delineates the boundaries you are working with, be it State, County, MCD, Census tracts, block groups, blocks, etc. ...
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  • 1,933
6 votes
Accepted

Converting coordinates in Florida, USA?

There are two UTM zones covering Florida : 16 and 17, but you are indeed not going anywhere with your coordinates. Northing with UTM starts at 0 at the equator, so you would be 1290 km North of the ...
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  • 48.6k

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