Flushing study assessment of a tidally active coastal embayment

In this paper four existing techniques for performing flushing studies of coastal embayments are applied to a small embayment and intercomparisons between the results carried out. Two of the methodologies employ detailed computer modelling whereas the other two rely on relatively simple flushing formulae. The underlying principles behind the techniques are briefly presented and their applicability to a particular coastal embayment is discussed. Flushing characteristics of an embayment on the West Coast of Ireland, Casheen Bay, were determined using each of the four techniques. Because the spatial extent of an embayment obviously directly affects the flushing characteristics, the embayment was subdivided into four segments and each method was applied to all four segments. The results of each analysis for each segment is presented and compared with the other similar analyses. A discussion of the results is presented, in which the suitability of the various methods is considered and the effects of subdividing the embayment into segments are highlighted. A summary of the work carried out and conclusions drawn is then presented and recommendations for future work in this field are made.