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USGS 7.5 Minute Topographic Maps (2003)
Theme7.5 Minute Topographic Maps (2000)

Index of quad names established by the USGS and the NY Department of Transportation.

High-quality PDFs of all current and historical topographic maps for each quad are freely available from the USGS Store (follow the 'Map Locator & Downloader' link on that page).

If you prefer, select quad sheets by map rather than by name.
MapsheetBrandreth Lake 7.5-minute Quad
ProviderNYS Department of Environmental Conservation
For additional datasets available from NYSDEC, see the list of DEC datasets at the NYSGIS Clearinghouse.
FormatGeoTIFF image .tif
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Coordinate System Universal Transverse Mercator | Meters | Zone 18
DatumNorth American Datum of 1983
Publication date January 29, 2003
Date added or updated November 30, 2000
This data set consists of images derived from scans of U.S.G.S. 7.5 minute quadrangle maps (Digital Raster Graphics). The images form a set of seamless tiles, 5,000 m on a side, from which the map collar information was removed. Images are GeoTIFF files in NAD83, UTM zone 18.
A DRG is useful as a source or background layer in a GIS, as a means to perform quality assurance on other digital products, and as a source for the collection and revision of DLG data.
Supplemental Information
1) Checking a sample of the DRGs produced by the U.S.G.S. indicated that the images were mis-registered by as much as 5 pixels (about 12 meters). Although the images were re-registered in an effort to reduce this error, perfect registration was not always possible. We found that some of the original images were scanned with distortion that could not be removed in the re-registration process. Thus, an unknown proportion of the images have errors which, when combined with any errors in the original maps, may exceed the limits of the National Map Accuracy Standards adhered to by the original maps. If a scanned image is to be used where accuracy at the 1:24,000 scale is needed, its registration accuracy should be verified. 2) The maps upon which the images are based used either metric contours in meters or English contours in feet. The data for contour unit, primary contour interval, and map publication date of the DRGs were put into the attribute table of a quadrangle boundary coverage. The information was obtained from an ASCII file emailed by the USGS. However, the USGS also attached a note in their email message about some problems when using information they provided "the relationship between a DRG and map publication date is not stored explicitly in USGS databases...but only inferred from dates and currency information. There are cases where the current DRG is not of the current map. For such cases, the map information in this list will be incorrect, and the contour information might be incorrect. There are other reasons why the date might not match the imprint dates on the paper map by +/- year. The only way to confirm the contour and date information is by visual inspection of the map collar, which is the definitive source of metadata". After checking map collar information on the available DRGs, the contour unit, contour interval, and map publication date are consistent with their values on the DRGs. The map date would be the photo revised or inspected date if a map has been modified based on the aerial photos taken after the map was first printed. 3) For more background on Digital Raster Graphics, refer to the USGS. To identify codes used in the data go to <>, the Index of New York State Digital Raster Graph (DRG) Quad Names established by the USGS and NY Department of Transportation (DOT).
Topicsimagery & base maps
File size3684 kilobytes
Use constraintsAcknowledgement of the USGS would be appreciated in products derived from these data.
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