An analysis of drainage channel stability in urbanizing watersheds was completed in this study for areas in Pima County, Arizona. Existing channel geometry and longitudinal slope were compared to original design channel geometry and longitudinal slope. Original design channels existed in undeveloped watersheds. Information on current amounts and types of development were gathered for each channel location as well as current channel geometry and longitudinal slope. The analysis of these data showed a significant relationship between basin urbanization and reduced channel stability.