Road-crossings at streams in Alberta's boreal mixedwood forest may act as human analogues of beaver dams by blocking flow, raising water tables upstream and lowering water tables downstream. I compared riparian vegetation on low-order streams with paired road crossings and beaver dams, to explore the idea that roads form a permanent, human-created beaver dam. My results indicate that water levels are raised upstream of road crossings but extensive interaction between road crossings and beavers confounded my analyses. Detailed field surveys of the beaver dams provided valuable data on beaver habitat use in boreal mixedwood forests. A 50-year chronosequence of air photos suggests that beavers may be the primary disturbance agent structuring riparian zones on low-order streams in the study area. Current forestry operating ground rules in Alberta require 30-60 m unharvested buffer strips on permanent streams but this study showed that beavers could be removing forest cover from entire buffer strips.