Plunge pool height of fall, the volume of water, the resistance of the rock below the pool and other factors. The impacting and swirling water, sometimes carrying rocks within it, abrades the riverbed into a basin, which often features rough and irregular sides. Plunge pools can remain long after the waterfall has ceased flow or the stream has been diverted. Several examples of former plunge pools exist at Dry Falls in the Channeled Scablands of eastern Washington. Plunge pools are fluvial features of erosion which occur in the youthful stage of river development, characterized by steeper gradients and faster water flows. Where
Coastline Plunge that takes them through a short enclosed tunnel. Once the tube exits the tunnel, it is taken up the side of the funnel part, going back and forth along the sides until it comes out the end through a water curtain into a splash pool, which it shares with Surge. Riders of this slide are also required to be no shorter than 48 inches. This is the only slide in the complex that is denoted as an "Aggressive Thrill Ride". Hyrdo is one of two slides added to Coastline Plunge in 2013. It is an orange slide in which riders