Towamba River is located on the far south coast of New South Wales. It is classed as a barrier river estuary and enters Twofold Bay via a permanently open entrance.
The Towamba River is the largest coastal river in the region and flows for 86 kilometres from the Great Dividing Range to the sea.
Water quality report card
As part of our water quality monitoring program we assess the water quality and ecosystem health of an estuary using a range of relevant indicators. We sample a subset of the estuaries between Wollongong and the Victorian border every 3 years. The most recent sampling in the Towamba River was completed over the 2023–24 summer, when 2 sites were sampled on a monthly basis.
This report card represents 2 water quality indicators that we routinely measure: the amount of algae present and water clarity. Low levels of these 2 indicators equate with good water quality. The numerical scores for these 2 indicators are averaged to give the overall grade.
Algae
Water clarity
Overall grade
The report card shows the condition of the estuary was excellent with:
- algae abundance graded excellent (A)
- water clarity graded excellent (A)
- overall estuary health graded excellent (A).
Grades for algae, water clarity and overall are represented as:
- A – excellent
- B – good
- C – fair
- D – poor
- E – very poor.
Go to estuary report cards to find out what each grade means, read our sampling, data analysis and reporting protocols, and find out how we calculate these grades.
We have monitored water quality in Towamba River since 2008. This table shows the water quality grades for this estuary over that time.
| Year | Algae | Water clarity | Overall grade |
|---|---|---|---|
| 2023–24 | A | A | A |
| 2008–09 | B | A | A |
Physical characteristics
| Estuary type | Barrier river |
|---|---|
| Latitude (ºS) | –35.84 |
| Longitude (ºE) | 150.19 |
| Catchment area (km2) | 91.9 |
| Estuary area (km2) | 1.8 |
| Estuary volume (ML) | 1410.9 |
| Average depth (m) | 1 |
Tidal exchange volume
Tidal exchange volume or tidal prism data is available for this estuary.
| Tide state | Flow (106 m3) | Local tidal range (m) | Sydney Harbour tidal range (m) |
|---|---|---|---|
| Ebb flow | 0.96 | 0.86 | 1.09 |
| Flood flow | 0.96 | 0.9 | 1.15 |
Notes: km2 = square kilometres; m = metres; m3 = cubic metres; ML = megalitres.
Water depth and survey data
Bathymetric and coastal topography data for this estuary are available in our data portal.
Land use
The Tomago River catchment is moderately disturbed, with almost 20% cleared for urban and rural residential areas and grazing at Tomakin, Mogo and Woodlands. About 80% of the catchment is forested.
National and marine parks
- The largest conservation area in the Towamba River catchment is the South East Forests National Park.
- This estuary does not flow into a marine park.
Citizen science projects
- The Far South Coast Conservation Management Network supports the local community to better manage native biodiversity. The network organises citizen science projects, provides information for private landowners, manages a local plant database, and coordinates events.
Community involvement
- The Bega River and Wetlands Landcare Group is a volunteer group dedicated to improving the health of the Bega River, wetlands and floodplains.
- The Far South Coast Landcare Association is a volunteer environmental and conservation organisation that works to improve management of local land and water.
Aerial view of Towamba River estuary.
Local government management
Local councils manage estuaries within their area. Where an estuary is attached to a marine park, marine park management teams are responsible for ensuring compliance with marine park zoning.
Bega Valley Shire Council manage this estuary.
Threatened species
This catchment contains lowland grassy woodland, an endangered ecological community, and the threatened Bega wattle.
Find out more about the biodiversity in our estuaries.