skip to content | skip to navigation

GIS.NY.GOV

NYS ITS GIS Program Office

Geographic Information Systems Clearinghouse

Department of Transportation
1:24,000 Scale Raster Quadrangles

Quadrangles produced by the NYSDOT Mapping and GIS Section are available as digital raster files. These files duplicate in digital form the map image that appears on the corresponding printed NYSDOT 1:24,000 scale quadrangle map. The files are raster images composed of pixels, and are not vectorized for use as intelligent GIS layers. However, they are well suited for use as a backdrop to other GIS layers to provide additional visual information or for on-screen, "heads-up" digitizing, as well as general display and plotting of the map image. The files may be used with a variety of UNIX and PC-based graphics, CAD, and GIS software packages.

Data Source

These files were created by scanning NYSDOT planimetric and topographic quadrangle maps.  The quadrangles were originally prepared by USGS but have been thoroughly updated (except for contours) by NYSDOT as part of an ongoing revision program. Quadrangles produced since 1990 have been revised using a full digital raster-based production process.

File Scan Types

The available files are the result of one of the following two production processes or scan types:

Coordinate System

All NYSDOT digital base map files use the Universal Transverse Mercator (UTM) Zone 18 projection/grid system based on the North American Datum of 1983 (NAD 83). UTM Zone 18 is used exclusively to georegister all files throughout New York State in a single zone with a single origin point.

Scale

These files were compiled at 1:24,000 scale and have positional accuracies of approximately 40 feet.

File Restrictions

These files are not copyright protected and have no use restrictions.

File Format

These files are offered in the industry-neutral TIFF (Tagged Image File Format) format compression type 4 (CCITT group 4). Each quadrangle raster file has a resolution of 508 DPI. Files include embedded GeoTIFF standard raster transformation parameters which position the raster file at correct scale and UTM Zone 18 coordinates. Additionally a MapInfo format table file (.tab), and an ESRI format world file (.tfw) are included.

File Size

File sizes average 2 MB (combining all layers). Individual file sizes may vary significantly from this average.

Software

These files have been tested to display properly in ESRI, Intergraph, and MapInfo products.

Map Symbols

An Acrobat format (PDF) brochure detailing Map Symbols used on Department of Transportation Quadrangles is available for download.