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Head induced by bedforms at the sediment-water interface (SWI) is typically represented in one of two ways: either by solving the RANS equations for the water column, or by a sinusoidal boundary condition defined by Elliott and Brooks (1997). Both of these methods have been used to model bedform-induced hyporheic exchange flux (HEF) on domains of constant shape. Under sufficiently fast flow conditions, however, bedform shape is irregular and evolves over time. For these conditions, neither method is fully appropriate: RANS is too computationally intensive, while the Elliott and Brooks boundary condition is based on measurements taken using rigid bedforms of an idealized triangular shape (Fehlman, 1985). We present a procedure for estimating head induced by arbitrarily-shaped bedforms using timelapse photos of dye tracer tests. At a given time t, an initial guess of head along the SWI is generated. The …