The effect of recreational landuse on streams has received little investigation, though these activities have the potential to degrade many aspects of stream ecosystems. We conducted a study to assess effects of recreational landuse on the structure and function of a pair of small urban fringe watersheds in southeastern Idaho. The Gibson Jack (GJ) watershed is predominantly managed for non-motorized use with hiking trails located away from stream banks, whereas the City Creek (CC) watershed, which receives much use from motorized vehicles, has extensive trails and unofficial roads that cross the stream in many places. Over 10 months CC had 97% more mean total suspended solids than GJ, and had 61% of its substrate embedded greater than 50%, while only 28% of substrate at GJ was embedded greater than 50%. City Creek also had slower leaf litter decay rates (0.03k/day) and higher Escherichia coli concentrations compared to Gibson Jack (0.05k/day). Structural differences in macroinvertebrate assemblages were also apparent between the two streams. Our results indicate how recreation, frequently considered a low impact landuse, can have an alarmingly strong affect on structural and functional processes, and emphasizes the need to reconsider management techniques in this region.