The sediment budget as a management tool: the Shoalhaven Coastal Compartment, southeastern NSW, Australia

Sediment budgets are fundamental approaches in coastal studies for allowing estimates

of volumes of sediments entering and exiting a selected area of the coast, resulting in

net erosion or accretion of that compartment under consideration. This assessment is

crucial for understanding current processes and predicting future effects of sedimentimpact

activities, promoting the sustainability of coastal environments over the next

centuries. In this paper we present a series of preliminary spatial, sedimentological and

geophysical analyses undertaken in order to understand the sources, sinks, transport

and pathways for the sediment budget of the Shoalhaven coast, a compartment whose

sediment provision is supplied primarily by the Shoalhaven River (draining a catchment

of 7,151 km2) and that stretches ~32 km from the rocky headland of Black Head at

Gerroa (north) to the Beecroft Peninsula near Currarong (south). Analysis included the

use of sub-bottom profiler, ground penetrating radar, RTK-GPS, aerial photographs,

satellite images, LiDAR, echosounding, computer modelling, as well as grain size

parameters from ~200 sediment (and mineralogy for selected) samples from the estuary,

beach and shoreface.