June 16, 2025

Georeferencing Historical Maps for Geospatial Analysis

Our project to create a dataset of historical water bodies in New Jersey began by finding maps of historical water bodies. Two atlases were used to locate historical water bodies in New Jersey. The first was Atlas of the Metropolitan District and adjacent country comprising the counties of New York, Kings, Richmond, Westchester and part of Queens in the state of New York, the County of Hudson and parts of the counties of Bergen, Passaic, Essex and Union in the state of New Jersey, published by Julius Bien & Co. in 1891. The scale of the atlas is 1:31,680 or 1 mile to 2 inches. Because the focus of this atlas is the New York City metropolitan area, the maps in this atlas only cover parts of Bergen, Passaic, Essex, and Union counties in New Jersey. The second atlas used was Atlas of New Jersey, published by Julius Bien & Co. in 1888. The scale of this atlas is 1:63,360 or 1 mile to 1 inch, so the detail is not as fine as the first atlas, but it covers the entire state of New Jersey. Both atlases were downloaded from the David Rumsey Map Collection.

The maps in these atlases were then georeferenced using Esri’s ArcGIS Pro Geographic Information System (GIS) software. Digitized historical maps generally do not have spatial reference information, so they cannot be used for geospatial analysis in GIS software. Georeferencing is the process of determining the precise location of these maps on the Earth’s surface (Esri, 2025).

The first step in georeferencing a digitized historical map is to define its coordinate system, which is the framework used to locate features on the Earth’s surface. The coordinate system used for this project is “NAD 1983 (2011) StatePlane New Jersey FIPS 2900 (US Feet).” This means it uses the 2011 update to the North American Datum 1983 horizontal geodetic datum for latitude and longitude, the North American Vertical Datum of 1988 for elevation, and that it is specific to New Jersey (NJDEP, 2021). The second step is to adjust the size and position of the map, so it is roughly in the correct position on the Earth’s surface. The third step is to add control points to fix the map’s precise location. Each control point is first placed in a specific location on the map being georeferenced, then placed in the same location on a reference map that has already been georeferenced.  Finally, an algorithm is applied to transform the map, so its control points align with the reference map (Esri, 2025). Once the maps in both atlases have been georeferenced, the tracing of water bodies can begin.

 

References:

Bien, J. R., Vermeule, C. C., US Coast and Geodetic Survey, Geological Survey of (1891). Atlas of the Metropolitan District and adjacent country comprising the counties of New York, Kings, Richmond, Westchester and part of Queens in the state of New York, the County of Hudson and parts of the counties of Bergen, Passaic, Essex and Union in the state of New Jersey. Retrieved from the David Rumsey Map Collection https://www.davidrumsey.com/luna/servlet/detail/RUMSEY~8~1~25291~930073:Title-Page–Atlas-Metropolitan-Dist?qvq=q:pub_list_no%3D%222730.000%22;lc:RUMSEY~8~1&mi=1&trs=16#.

Cook, G. H., Geological Survey of New Jersey, Vermeule, C. C. (1888). Atlas of New Jersey. Retrieved from the David Rumsey Map Collection  https://www.davidrumsey.com/luna/servlet/detail/RUMSEY~8~1~26216~1100491:N-J–state-map-?sort=pub_list_no_initialsort%2Cpub_date%2Cpub_list_no%2Cseries_no&qvq=w4s:/what%2FAtlas%2BMap%2Fwhere%2FNew%2BJersey%2Fwhen%2F1888;sort:pub_list_no_initialsort%2Cpub_date%2Cpub_list_no%2Cseries_no;lc:RUMSEY~8~1&mi=0&trs=20 .

Esri. (2025). Overview of georeferncinghttps://pro.arcgis.com/en/pro-app/latest/help/data/imagery/overview-of-georeferencing.htm.

New Jersey Department of Environmental Protection (2021). NJDEP MAPPING AND DIGITAL DATA STANDARDS (February 7, 2021). https://dep.nj.gov/wp-content/uploads/gis/njdep_gis_spatial_data_standards_edition_2_7_2021-1.pdf.