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I am trying to line up a US Census Block shapefile with another shapefile that has lat/long points (i created it from a csv), but the points are not lining up with the Census shapefile.

Here is some info that i can offer: The census file is in WGS 1984 Web Mercator Auxiliary Sphere The points shapefile is in an unprojected lat/long

I have projected the Points shapefile to GCS_WGS_1984 I have projected the Census shapefile to WGS 1984, WGS Web Mercator, NAD 1983, NAD 1983 Albers.

In most scenarios, the points shapefile is either really really small in the center of the map, or off to the side and kind of tilted.

Census blocks:

Census Blocks

Data Type: Shapefile Feature Class

Shapefile: C:\Users\US_blck_grp_2010.shp

Geometry Type: Polygon

Coordinates have Z values: No

Coordinates have measures: No

Projected Coordinate System: WGS_1984_Web_Mercator_Auxiliary_Sphere Projection: Mercator_Auxiliary_Sphere

False_Easting: 0.00000000

False_Northing: 0.00000000

Central_Meridian: 0.00000000

Standard_Parallel_1: 0.00000000

Auxiliary_Sphere_Type: 0.00000000 Linear Unit: Meter

Geographic Coordinate System: GCS_WGS_1984

Datum: D_WGS_1984

Prime Meridian: Greenwich

Angular Unit: Degree

Points Shapefile:

enter image description here

Data Type: Shapefile Feature Class

Shapefile: C:\Users\XYrawCA_GISselection.shp

Geometry Type: Point

Coordinates have Z values: No

Coordinates have measures: No

Geographic Coordinate System: GCS_WGS_1984

Datum: D_WGS_1984

Prime Meridian: Greenwich

Angular Unit: Degree

Update

This is the image i see when I Reproject the points shapefile to WGS 1984. Technically, its unchanged from when I intitaly load the file. enter image description here

  • Did you download the file directly from the Census bureau, or another source? It starts as NAD83 before reprojecting if from Census bureau. Please also confirm that you reprojected (rather than assign/define the projection). – smiller Apr 25 '18 at 14:10
  • You're currently in a projected coordinate system with the Census Bureau file (Web Mercator?) and in a geographic coordinate system with the points file (WGS84). – smiller Apr 25 '18 at 14:15
  • Hi, yes I downloaded the Census Block Group shapefile from the Census Bureau. And yes, for the Block Group shapefile, i have "reprojected'. For the points shapefile i typically "define projection". And yes, I do understand that I am running both a PCS and GCS, but im not sure what to do to reconcile the issue. Any reprojection I do seems not to work. Ive also tried "recalculating" the feature extent in ArcCatalog, but it doesnt seem to do anything. – Fred Mortensen Apr 25 '18 at 14:25
  • and for what it is worth, i downloaded the blockgroup file from here: census.gov/geo/maps-data/data/tiger-data.html – Fred Mortensen Apr 25 '18 at 14:28
  • I assume they were merged since I don't recall seeing a full US block group file. My feature extent is different for the block groups, but I think that's because I'm working with CONUS. Let's focus on the XY data. Try reloading it and specifying (during the Display XY Data) what it was collected in (typically WGS84). Then reproject it to match your Census layer. – smiller Apr 25 '18 at 14:32

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