Live-bed scale models of estuaries have long been impossible due to unwanted scale effects. Especially generating tidal flows and sufficient sediment mobility as in estuaries proved challenging, in contrast with meandering and braided river scale experiments where gradient could be increased to obtain sufficient mobility. Here we present 1:2000 scale experiments of estuaries with self-formed, dynamic channel-bar patterns in sand. Tidal currents were obtained by periodic tilting. In contrast with predictions from classic Froude and live bed procedures for scale models, the experiments produce bar morphologies closely resembling natural systems such as the Western Scheldt. Various scale effects were avoided by using poorly sorted coarse sand. With the advantage of experimental control, effects of fairway dredging and dumping could be tested and were shown to have large effects on intertidal habitat. The novel experimental setup, called Metronome, now allows a large variety of tidal system scale models.
