The Impact of Sediment-water Interactions on Water Quality in Wellstead Estuary, Gordon Inlet, and Beaufort Inlet, South-western Australia

In early autumn 2006 (14th March to 4th April), Geoscience Australia conducted a field survey to investigate the major processes controlling water quality in Wellstead Estuary, Gordon Inlet and Beaufort Inlet. This project aimed to address critical knowledge gaps in understanding the impact of sediment-water interactions on water quality in each estuary, in particular, to identify the major controls on nutrient abundance and availability.

The impacts of sediment-water interactions on overall water quality took into account:
1. shallowness of the estuaries and long water residence time;
2. productivity of microbenthic algae; and
3. the type of aquatic plant growth.

Recommendations for the future management of these estuaries included:
1. Reducing nitrogen loads from the catchments of Wellstead Estuary and Gordon Inlet, and reducing the phosphorus loads from the catchment of Beaufort inlet;
2. Monitoring the abundance of macroalgae in Wellstead Estuary, the abundance of macrophytes in Gordon Inlet and the water column Chl-a concentrations in Beaufort Inlet.