Nullica River is located on the south coast of New South Wales. It is classed as a lagoon with an entrance that is intermittently open and closed to the ocean.
This estuary flows into Nullica Bay, which forms part of Twofold Bay south of Eden. Most of the catchment is forestry land.
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 Nullica 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 good with:
- algae abundance graded excellent (A)
- water clarity graded fair (C)
- overall estuary health graded good (B).
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 Nullica River since 2011. This table shows the water quality grades for this estuary over that time.
| Year | Algae | Water clarity | Overall grade |
|---|---|---|---|
| 2023–24 | A | C | B |
| 2011–12 | B | B | B |
Physical characteristics
| Estuary type | Lagoon |
|---|---|
| Latitude (ºS) | –37.09 |
| Longitude (ºE) | 149.87 |
| Catchment area (km2) | 54.8 |
| Estuary area (km2) | 0.3 |
| Estuary volume (ML) | 176.1 |
| Average depth (m) | 0.6 |
Notes: km2 = square kilometres; m = 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 catchment of Nullica River is relatively undisturbed, with 95% currently forested, most of which is managed by Forestry Corporation. A small amount of the lower catchment around Nullica and Boydtown is cleared for grazing and rural residential properties.
National and marine parks
- South East Forests National Park is the largest conservation area in this catchment.
- This estuary does not flow into a marine park.
Community involvement
- 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 Nullica 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 manages this estuary.
Threatened species
The forests around Nullica River estuary provide a stronghold for the critically endangered smoky mouse.
Find out more about the biodiversity in our estuaries.