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The near-stream groundwater environment is a unique ecotone composed of the hyporheic zone and riparian/floodplain groundwater. Preferential flow paths through sediments are areas of substantially higher permeability than surrounding media. Macropores and soil pipes are a type of preferential flow path where conduit-like voids occur in soil as a result of biological and physical processes. Recent papers show that soil pipes exist in streambanks and have the potential to enhance the exchange of water and solutes between the channel and riparian groundwater. However, these prior streambank studies were confined to isolated locations, hence we do not know if streambank soil pipes are a limited or widespread phenomenon. Here we quantified the abundance, distribution, and geometry of naturally occurring streambank soil pipes >1.0 cm in diameter in 20 streams across 5 physiographic provinces in the eastern United States. We found 998 streambank soil pipes across all 20 streams, demonstrating their ubiquity in the region. Pipe openings were, on average, 4.0 cm wide, 3.4 cm high, spaced 2.2 m apart, and 26.0 cm above baseflow water surface elevation (WSEL) in the channel. Most pipes were above baseflow WSEL, with only 5.7% below. Pipes were more abundant in fine-grained soils, which generally have higher cohesivity and lower hydraulic conductivity. Soil pipes were more abundant in 3 of the 5 physiographic provinces, likely because of greater presence of fine-grained soils. At a smaller scale, streambanks with greater longitudinal heterogeneity of soil texture often had greater spatial heterogeneity of pipe density. However, given the effort required to characterize a relatively small number of streams, and because stream order and soil texture are related to physiographic province, it was not possible to statistically test the effect of these factors. This work represents the first attempt to characterize streambank soil pipe abundance and distribution across a range of stream orders and physiographic provinces. The ubiquity of soil pipes in the region implies their effect on bidirectional hyporheic exchange is likely equally widespread. These results may have water-quality implications, where streambank soil pipes could enhance hyporheic exchange but reduce the filtering capacity of riparian buffer zones. [ABSTRACT FROM AUTHOR]