Deep Creek

Our water quality monitoring program has shown Deep Creek to have good water quality. Find out more about the estuary and its unique features.

Deep Creek estuary is a medium-sized lagoon with an intermittently closed entrance. Located north of Nambucca Heads on the north coast of New South Wales, the estuary is typically open to the sea via a shallow constricted entrance.

Historically, artificial entrance opening has occurred at Deep Creek estuary when the lagoon has closed. The lower estuary supports a large area of tidal flats, mangroves and saltmarsh, and is a popular fishing and swimming spot.

Estuary health and features

Water quality

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 located between the Queensland border and Taree every 3 years. The most recent sampling in Deep Creek was completed over the 2018–19 summer when 2 sites were sampled on a monthly basis.

Deep Creek water quality report card for algae and water clarity showing colour-coded ratings (red, orange, yellow, light green and dark green, which represent very poor, poor, fair, good and excellent, respectively). Algae is rated 'good' and water clarity is rated 'good' giving an overall rating of 'good' or 'B'.

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 good with:

  • algae abundance graded good (B)
  • water clarity graded fair (C)
  • overall estuary health graded good (B).

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.

We have monitored water quality in the Deep Creek since 2012. This table shows the water quality grades for this estuary over that time.

Deep Creek historic water quality grades from 2012-13 for algae and water clarity. Colour-coded ratings (red, orange, yellow, light green and dark green represent very poor (E), poor (D), fair (C), good (B) and excellent (A), respectively).

Grades for algae, water clarity and overall are represented as:

  • A – excellent
  • B – good
  • C – fair
  • D – poor
  • E – very poor.

Physical characteristics

Estuary type: Lagoon

Entrance
location 		Latitude (ºS) –30.6
Longitude (ºE) 153.01
Catchment area (km2) 89.8
Estuary area (km2) 1.7
Estuary volume (ML) 1387
Average depth (m) 1.3

Tidal exchange volume

Tidal exchange volume or tidal prism data is available for this estuary. This tidal prism was measured in 2002.

Tide state Flow
(106 m3)		 Local tidal
range (m)		 Sydney Harbour
tidal range (m)
Ebb flow 0.22 0.25 1.67
Flood flow 0.28 0.28 1.72
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 Deep Creek catchment is highly disturbed. Most land-use change has been driven by grazing and horticulture throughout the valley. A lot of the low-lying area adjacent to the estuary and the steep upper reaches of the catchment remain as forest, making up most of the total catchment area.

National and marine parks

  • Bollanolla Nature Reserve is the largest conservation area within the Deep Creek catchment.
  • This estuary does not flow into a marine park.

Community involvement

  • Nambucca Valley Landcare provides workshops and volunteer work opportunities around the Nambucca Valley region, including Deep Creek.
Deep Creek

Local government management

Local councils manage estuaries within their area unless the estuary is attached to a marine park.

Deep Creek estuary is managed by Nambucca Shire Council. More information about estuary management is available on the council’s Coast and estuary management webpage.