Observation of wave set-up height in a river mouth

Field observation data of water level at three river mouths are collected and analyzed in order to find quantitative relationship between wave set-up height at a river entrance and wave characteristics. At a relatively bigger river mouth which is protected by two jetties, wave set-up cannot be observed in the river entrance, whereas at smaller river mouths, distinct water level rise above tidal elevation can be observed during the period high waves. An empirical expression is obtained for the relationship between wave set-up height and deep water wave height, which shows slight difference from a previous expression for wave set-up at the shoreline on a sloping beach.