Sediment Monitoring

Hornsby Shire Council has been monitoring the quality of the sediment along the Lower Hawkesbury since the late 1990's. Explore the latest data (2013) by selecting a parameter from the list below.

Ammonia  |  Copper  |  Lead  |  Mercury  |  PAH  |  TKN  |  TOC  |  TPH


Concentration (mg/kg)
< 20 20 to 30 30 to 40 40 to 60 > 60
The Interim Sediment Quality Guideline for this parameter is 50 mg/kg (ANZECC/ARMCANZ, 2000)

The latest results (2013) are shown in the map at 52 locations. A wide range of chemical sediment analyses were undertaken including trace metals and elements (Ag, Al, As, Ba, Be, Bo, Ca, Cd, Co, Cr, Cu, Fe, Hg, Mg, Mn, Ni, P, Pb, Sr, V and Zn); PAHs, TPHs, PCBs, OCs, OPs, nutrients (TKN, TOC, NOX, reactive inorganic phosphorus); Ammonia and TOC; antifouling biocides (Diruon, chlorothalonil, Irgarol 1051 and Diclorofluanid); and concentrations of synthetic pyrethroids and 200 individual organic contaminants (including carbamates, triazines/triazoles, phenoxy acid herbicides, urea herbicides, fungicides and insecticides).

Overall contaminant concentrations in the Lower Hawkesbury Estuary were generally low in comparison to urbanised and industrialised areas in other parts of Australia. Concentrations through time have remained stable or decreased slightly in some areas. Further information on the spatial distribution and temporal changes in sediment quality from the Lower Hawkesbury can be found here.

This project has been partly funded through the NSW Office of Environment and Heritage Estuary Grants.