Evaluation of Sand Waves in an Estuary

The Bella-Williamson rate of sediment turnover-organic content of sediment (RST-OCS) dissection plane method integrates relevant physical, chemical, and biological analyses in order to estimate the chronic impacts of dredging on estuarine ecosystems. A spectral analysis by a finite Fourier transform of estuarine sand waves is presented which only requires a spatial sand wave record that is relatively easy to measure in contrast to stochastic analyses which require both spatial and temporal observations of sand wave profiles. The total energy content (or, equivalently, the statistical variance of the spatial sand wave profile) and the equilibrium subrange of the wave number spectrum provide readily observable measures of the RST in an estuary; economic savings, promise to be significant. In addition, a uniform -3 power law for the wave number equilibrium subrange is presented which offers an opportunity to obtain a sand wave frequency spectrum without a temporal sand wave profile record through a dispersion transformation proportional to the bed shear velocity.