(a) Photograph and schematic of the liquid dam: a jammed front acts as a moving barrier while a thin overflow layer sustains propagation. This simple physical picture predicts a front speed scaling as V ~ τ_c(ϕ)²/ρgη₀(ϕ) and is validated across different shear-thickening suspensions. (b) Stairwaves: a train of liquid dams spontaneously forms when an initially horizontal layer is tilted, illustrating the robustness of the mechanism beyond dam-break flows (adapted from [4]).