The geographic information system pilot project on Pool 13 of the Upper Mississippi River System was initiated to evaluate system-wide application of various methods of capturing, processing and converting resource data. Classification schemes were developed for two data themes: land cover/land use (vegetation) and aquatic areas. Evaluation of 1:15,000 scale aerial photography indicated that (1) color infrared transparencies were essential for accurately mapping major vegetation classes and vegetation units less than 1 acre; (2) color infrared prints were essential for field work (delineating work areas on the photos and identifying in the field; (3) true color (Ektachrome) transparencies and prints were not useful vegetation types in mapping the land cover/land use or aquatic areas themes; and (4) black and white infrared prints were useful for identifying water regimes in the land cover/land use theme but were not useful for identifying vegetation types or aquatic areas. The 1:15,000 scale photography provided the detail needed for site specific mapping and was useful for mapping general features. Automated procedures were developed to produce the aquatic areas coverage from the land cover/land use coverage created in the ARC/INFO geographic information system, which saved manual photo interpretation and drafting time. The conventional three step process of manual photo interpretation, drafting and digitizing provided more accurate mapping of complex data themes compared to digital image processing. Image processing technology requires further improvements before it is suitable for high resolution mapping over large areas. Manual digitizing was more accurate and economical than a scan digitizing process used to capture thematic data. However, evaluation of other scanning technologies is recommended for future Upper Mississippi River System mapping efforts because the technology continues to improve in quality and accuracy, while cost steadily decreases. Lookup tables and macros were developed for converting ARC/INFO data into two other geographic information system formats: EPPL-7 (PC based version of the Environmental Planning and Programming Language developed by the Minnesota State Planning Agency) and GRASS (Geographic Resources Analysis Support System developed by the U.S. Army Corps of Engineers Construction Engineering Research Laboratory).