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Tracer studies during catchment‐scale sprinkler experiments illuminate the pathways of subsurface flow in a small, steep catchment in the Oregon Coast Range. Bromide point injections into saturated materials showed rapid flow in bedrock to the catchment outlet. Bedrock flow returned to the colluvium, sustaining shallow subsurface flow there. The bromide peak velocity of ∼10⁻³ m s⁻¹ exceeded the saturated hydraulic conductivity of intact bedrock. This, and the peak shapes, verify that fractures provide important avenues for saturated flow in the catchment. Deuterium added to the sprinkler water moved through the vadose zone as plug flow controlled by rainfall rate and water content. Ninety‐two percent of the labeled water remained in the vadose zone after 3 days (∼140mm) of sprinkling. Preferential flow of new water was not observed during either low‐intensity irrigation or natural storms; however, labeled …