Abstract Graph models of fractured media commonly vary edge weights while retaining one directed topology. We tested this assumption in a measured three‐dimensional rough fracture using steady Navier‐Stokes flow, flux‐closure recirculation zones, directed voxel graphs, and conservative graph transport. As the Reynolds numbers increased from 5 to 400, 11.9% of common edges reversed direction, cyclic nodes expanded from 0.073% to 14.35%, and the number of significant recirculation zones increased from 0 to 65. Median and 90th‐percentile travel times changed little, but the 99th percentile increased by 16.8% as late paths increasingly accessed recirculation‐linked strongly connected components. At the high flow rate, a uniformly scaled low‐inertia graph underpredicted the 99th percentile by 16.1%; matching the global Peclet number also failed to collapse transport. The results show that edge directions vary with Reynolds number and carry information about late retention associated with inertial recirculation.

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