Overview

Digital Elevation Models (DEM) are interpolated from raw USGS data. Map features larger than 90 meters will generally be represented. The contour lines are created from points arranged in columns aligned with the UTM grid. The distance between adjacent points is 30 meters. A contour interval is specified when the map is ordered. The recommended interval for 1:24,000 scale data should be 40 feet for best accuracy and not less than 20 feet. Adjacent 7.5 minute quadrangles will not share common boundary elevation points even though the maps may line up with each other. ADCi will edge-match the contours across quadrangle boundaries. Upon special request we can provide index contours and contour labels. Please click on the information link below for free downloadable samples.

Specifications

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