Pittwater is situated in the Sydney Metropolitan district of New South Wales. Pittwater is a tide-dominated drowned valley estuary with an open entrance situated in the Sydney Metropolitan Region of New South Wales. It is one of the bodies of water that separate the Greater Sydney Metropolitan Region from the Central Coast.
Pittwater is a large embayment connected to the Hawkesbury River estuary where the river enters the sea. Pittwater is popular for boating, fishing, sailing and swimming.
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 have supported Northern Beaches Council develop and carry out a monitoring program to assess the water quality of estuaries in their local government area. Sampling is carried out fortnightly between October and April each year. Five sites are sampled in Pittwater.
The monitoring program has been ongoing since 2017. The most recent sampling was completed over the 2021–22 summer.
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.
Algae
Water clarity
Overall grade
The report card shows the condition of the estuary was excellent with:
- algae abundance graded good (B)
- 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 Pittwater since 2017. This table shows the water quality grades for this estuary over that time.
| Year | Algae | Water clarity | Overall grade |
|---|---|---|---|
| 2017–18 | A | A | A |
| 2018–19 | A | A | A |
| 2019–20 | A | A | A |
| 2020–21 | B | A | A |
As part of our Beachwatch program we assess swimming suitability at 10 swimming sites in Pittwater using microbial indicators. We collect samples at each site weekly between October and April, and monthly from May to September, to calculate the suitability grade. Sampling is ongoing. Each grade reflects the most recent 100 water quality results to April 2022. Find out more about how we monitor beach water quality.
Local government area: Northern Beaches
| Swim site name | Grade |
|---|---|
| Barrenjoey Beach | Good |
| Great Mackerel Beach | Very good |
| The Basin | Very good |
| Paradise Beach Baths | Good |
| Clareville Beach | Good |
| Taylors Point Baths | Good |
| North Scotland Island | Good |
| Elvina Bay | Very good |
| South Scotland Island | Good |
| Bayview Baths | Poor |
Estuarine, lake and lagoon water can sometimes be unsuitable for swimming, especially after rainfall when stormwater and wastewater can overflow into swimming areas. Learn more about what the grades mean and how we grade swimming sites on the Beachwatch How we report webpage.
Physical characteristics
| Estuary type | Drowned valley |
| Latitude (ºS) | –33.58 |
| Longitude (ºE) | 151.32 |
| Catchment area (km2) | 50.8 |
| Estuary area (km2) | 18.4 |
| Estuary volume (ML) | 181,836.2 |
| Average depth (m) | 9.9 |
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 Pittwater catchment is moderately disturbed with urban areas to the south east and the conservation area of Ku-ring-gai Chase National Park to the north west. Pittwater is a popular site for water recreation, such as sailing and fishing.
National and marine parks
- Ku-ring-gai Chase National Park is the largest conservation area in this catchment.
- This estuary does not flow into a marine park, but it is adjacent to the Barrenjoey Head Aquatic Reserve.
Community involvement
- The Northern Beaches Coastal Environment Centre is a community-based learning centre that focuses on raising awareness about the local coastal environment and how to care for it.
Aerial view of Pittwater estuary.
Local government management
Local councils manage estuaries within their area unless the estuary is attached to a marine park. Northern Beaches Council manages this estuary.
Threatened species
This estuary supports the endangered ecological community, coastal saltmarsh, which provides habitat for many species, including the endangered bush stone-curlew.
Read more about the biodiversity in our estuaries.