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The general consensus that urbanization results in dramatic changes in stream hydrology, such as higher peak flows and greater flashiness, has not been definitively tested for aridlands, which are themselves characterized by these very same hydrograph properties. This study analyzed streamflow records from 33 watersheds of central and southern Arizona, USA to determine how hydrograph characteristics varied across a range of development. Relationships of hydrologic parameters to urbanization were not evident when all catchments were considered. However, when only catchments small enough (<100 km2; n=16) to escape damming or diversion were considered, flashiness index and coefficient of variation of daily flow both decreased with increased extent of development. Examining flow data at sub-daily temporal resolution indicated that the magnitude of hydrograph rise and fall rates decreased with development. This relationship is opposite that found for many streams in more humid regions. Evidence suggests that engineered retention basins are one driver behind this observation. As in humid systems, there were more high-flow events in the urban desert streams compared to non-urban streams. However, this was linked to the high quantity of zero-flow days in desert systems where urban streams had more days with measurable flow. This may be due to novel urban sources of baseflow, such as irrigation overflow. Results of the study suggest that the urban stream syndrome manifests differently in aridland systems where urbanization appears to increase water retention and lead to less variable flows in stream ecosystems. The data presented here include characteristics of the study catchments, and metrics of flashiness derived from hydrographs of these systems during the study period (2003-2016).