Bathymetric mapping in the coastal shallow water zone is a challenging and costly process using traditional survey methods. Because of this, much of this region worldwide remains uncharted and, therefore, is poorly understood. Multispectral satellite imagery has proven to be a practical alternative tool in predicting water depth in coastal zones, though influences on its performance and accuracy are not fully understood and vary according to local environmental conditions. This study explored the suitability of a satellite derived bathymetry (SDB) methodology in Irish Atlantic coastal waters. Using imagery captured at a range of spatial, spectral and temporal resolutions by the RapidEye and Landsat 8 satellites, we explored the correlation between performance, accuracy and image resolution, demonstrating that sensor wavelength is the key limiting factor in optical penetration of water and also accurate delineation of the gradient on the seafloor. We further applied this data in a study of submarine geomorphology in an INFOMAR priority bay. Although the SDB accuracy is insufficient for high accuracy bathymetry products, nevertheless, they are considered beneficial in a variety of other applications in sensitive disciplines such as environmental monitoring, seabed mapping, or coastal zone management.