Bermagui River

Physical characteristics

Latitude (ºS)-36.42
Longitude (ºE)150.07
Catchment area (km2)183.5
Estuary area (km2)1,22.2
Estuary volume (ML)32160.2
Average depth (m)41.1
Roy et al. (2001) classification5III/5/C
Entrance condition6O/T
  1. Derived from DECCW (2010) NSW estuaries and coastal catchments spatial database.
  2. Includes area mapped as open water (see note 1), mangrove and saltmarsh areas (Creese R. G., Glasby T. M., West G. and Gallen C. (2009) Mapping the habitats of NSW estuaries. Industry & Investment NSW Fisheries Final Report Series 113. Port Stephens, NSW, Australia.
  3. Based on areas at 0.6 m AHD (Roper T., Creese B., Scanes P., Stephens K., Williams R., Dela-Cruz J., Coade G. and Coates B. (2011) Assessing the condition of estuaries and coastal lake ecosystems in NSW. Office of Environment and Heritage, Sydney).
  4. Estimated by dividing the total volume at 0.6 m AHD by the total surface area of the estuary including mangrove areas but excluding saltmarsh (Roper et al., 2011)
  5. Estuary group: I = oceanic embayment, II = tide dominated estuary, III = wave dominated estuary, IV = intermittently closed estuary V = freshwater bodies
    Estuary type: 1 = ocean embayments, 3 = drowned valley estuary, 5 = barrier estuary, 6 = barrier lagoon, 7 = interbarrier estuary, 8 = saline coastal lagoon, 9 = small coastal creeks, 11 = brackish barrier lake. Evolution stage: A=youthful, B=intermediate, C=semi-mature, D=mature.
    (P. S. Roy, R. J. Williams, A. R. Jones, I. Yassini, P. J. Gibbs, B. Coates, R. J. West, P. R. Scanes, J. P. Hudson and S. Nichol (2001) Structure and Function of South-east Australian Estuaries. Estuarine, Coastal and Shelf Science 53, 351-384)
  6. Entrance conditions: O = open, T = trained, I = intermittent.

Tidal prism

The volume of water moving past a fixed cross section during each flood tide or ebb tide (i.e. slack water to slack water), is referred to as the tidal prism of an estuary.

The following table shows the measured tidal prism at the location specified, along with the tidal range for near the measurement site and at Sydney Harbour.

Location:     150m from the ocean on 7/11/90

Tide stateFlow
(106 m3
tidal range (m)
Sydney Harbour
tidal range (m)
Ebb flow2.51.551.56
Flood flow

Tidal survey

Tidal surveys measure the hydrodynamic behaviour of an estuary during a full tidal cycle. The parameters measured include velocity, water levels, salinity, temperature and pH.

The following tidal surveys have been undertaken on this estuary. A map shows the location and plots of the flows and water levels for the most comprehensive survey.

Copies of tidal survey reports are available from the Estuary Management Program

DateData collectedFigureReport
Jun 1978Current metering at three lines, two tideboards - velocity, discharge, cross sections, temp/salinity and suspended samples.-MHL276
Nov 1990Current metering at four lines, five tideboards, velocity, discharge, cross sections, temp/salinity, dissolved oxygen and drogue tracking.1988-55.pdfMHL590
Mar to Jun 1991Four floatwell recorders installed for four months for a tidal plane analysis.-MHL597

Hydrographic survey

The hydrographic survey provides the depth and physical characteristics of the estuary.

The metadata associated with the survey can be found on the map sheets provided.

Map sheet number DescriptionScale    Size
9091sh1.pdfIndex plan1:2000406.8kb
9091sh2.pdfBermagui River (north western shore)1:500272.2kb
9091sh3.pdfBermagui River (River Street)1:500282.2kb
9091sh4.pdfBermagui River1:500259.2kb
9091sh5.pdfBermagui River (Mill Street)1:500258.9kb
9091sh6.pdfBermagui River (Wapengo Street)1:500183.3kb
9091sh7.pdfBermagui River entrance1:500218.1kb
9091sh8.pdfBermagui River (south western shoreline)1:50089.7kb
9091sh9.pdfBermagui River (southern shoreline)1:500214.6kb
9091sh10.pdfBermagui River (southern shoreline)1:500237.0kb
9091sh11.pdfBermagui River entrance channel1:500165.8kb
9147sh1.pdfIndex plan & cross sections - Bermagui River (Jaggers Bay)1:1000 H 1:200 V475.7kb
9147sh2.pdfCross sections - Bermagui River (Rose Bay)1:1000 H 1:200 V447.3kb
9147sh3.pdfCross sections - upper Bermagui River1:1000 H 1:200 V536.7kb
9091.txtBermagui River xyz dataN/A126.4kb
54569s01.pdfIndex plan1:1250342.1kb
54569s02.pdfBermagui River entrance & offshore1:500253.4kb
54569s03.pdfBermagui River (downstream Bridge Road)1:500273.0kb
54569s04.pdfBermagui River entrance & Harbour1:500337.9kb
54569s05.pdfBermagui Harbour1:500335.6kb
54569.txtBermagui Harbour xyz dataN/A123.9kb
Page last updated: 26 April 2012