Biotic communities in ephemeral streams are affected by flooding and drying disturbances. Organisms may be limited in their distribution along ephemeral stream networks based on their life history adaptations, with more mesic and flood-adapted species often excluded from headwater reaches where drying may be more severe and flooding less frequent or intense. Understanding the relative influence of drought and flooding on species persistence in ephemeral streams is crucial for conserving biodiversity, especially where land use development alters natural hydrologic patterns. In this study, we explored whether woody riparian vegetation communities along headwater ephemeral streams were influenced by flooding and drying across a gradient of watershed urbanization in San Antonio, Texas. We measured riparian vegetation communities along eight stream reaches and categorized species as to their drought tolerance, water use, and heat tolerance. We also categorized surface elevation profiles and measured flow patterns and upstream watershed land use at each reach. Flood frequency correlated positively with watershed impervious cover and species diversity correlated negatively with impervious cover, but species diversity did not correlate with flood frequency. Multivariate ordination indicated community composition differences between sites were structured by gradients of urban development, flood frequency, and abundance of drought and heat tolerant species. We also observed a positive correlation between watershed impervious cover and abundance of low water use species, despite higher flood frequency in more urban sites. Furthermore, elevation above the stream channel did not strongly influence community composition. Together, these results suggest woody riparian communities in these headwater ephemeral streams are responding to complex interactions between flooding and drying as influenced by urbanization. Although urban development increases flood frequency, events are of short duration within long periods of hot, dry conditions, which may increase with further urban development and climate change in the region.