Our water quality monitoring program has shown Back Lagoon to have excellent water quality. Find out more about the estuary and its unique features.
Back Lagoon is located on the south coast of New South Wales on the outskirts of Merimbula. It is classed as a lagoon with an intermittently closed entrance. The entrance is managed by Bega Valley Shire Council to reduce impacts of foreshore inundation.
This estuary is particularly dynamic due to the relatively large size of the catchment compared to the lake. The estuary supports extensive seagrass beds.
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 Back Lagoon was completed over the 2017–18 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 report card shows the condition of the estuary was excellent with:
Find out more about our estuary report cards and what each grade means. Read our sampling, data analysis and reporting protocols and find out how we calculate these grades.
Estuary type: Lagoon
| Entrance location |
Latitude (ºS) | –36.88 |
|---|---|---|
| Longitude (ºE) | 149.93 | |
| Catchment area (km2) | 31.4 | |
| Estuary area (km2) | 0.4 | |
| Estuary volume (ML) | 215.9 | |
| Average depth (m) | 0.6 | |
Bathymetric and coastal topography data for this estuary are available in our data portal.
The catchment of Back Lagoon has low disturbance with over 80% remaining forested. Urban and grazing areas each occupy about 5% of the catchment.
Local councils manage estuaries within their area unless the estuary is attached to a marine park. Bega Valley Shire Council manage this estuary.
Back Lagoon estuary supports extensive seagrass meadows and is home to a number of other estuarine species.
Find out more about the biodiversity in our estuaries.