Application of the wave pump concept to simulate tidal anomalies in Lake Conjola, NSW, Australia

Abstract

The present paper applies the wave pump concept to a flooding event at Lake Conjola, Australia. We explain how the raised water level in the lake was caused by waves with large height and very long period pumping water into the lagoon across a berm separating the lagoon from the ocean with the nominal wave set up effects. Outflow through the entrance channel, modeled as critical flow over a weir, results in less agreement with measurements compared to that of approximating it as a channel with finite length. An inverse analysis indicates that the entrance scoured out to become more efficient during the wave event, returning to normal cross section after the event. This insight was utilized to adjust the entrance area in a forward model to get optimal fit with measured water levels. Finally, the wave pump concept was confirmed using a two node model that reflected the actual surface areas of two lakes in series.