Slope and aspect classifications of Lake Tahoe Basin, California and Nevada

A geographic information system was used to develop maps of slope and aspect data for the Lake Tahoe basin of California and Nevada. The maps were pro- duced at 1:100,000 scale by using digital-elevation data derived from 1:24,000-scale maps. The maps show slope (steepness) and aspect (compass-direction) data for the basin. Classes for slope data were set as follows: 0 percent, >0 to 2 percent, >2 to 5 percent, >5 to 10 percent, >10 to 15 percent, >15 to 20 percent, >20 to 30 percent, >30 to 50 percent, and >50 to 100 percent. Classes for aspect data were limited to the eight points of the compass (north, northeast, east, southeast, south, southwest, west, and northwest) and level land.