Manning River

We collaborate with local government to monitor the condition of Manning River. Find out more about the Manning River estuary and its unique features.

The Manning River estuary is situated on the mid-north coast of New South Wales. It is a large 250-kilometre-long barrier river with a permanently open trained entrance at Harrington (pictured), and a second predominantly closed entrance where the south arm reaches the sea near Old Bar.

The Manning River drains the fifth biggest catchment on the New South Wales coast. It is one of Australia’s few large river systems that has not been dammed for water supply purposes. It dominates the Manning Valley, supporting commercial industry and providing enormous recreational and ecological value.

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 9 sites on a monthly basis over summer in the Manning River estuary as part of a collaborative program with MidCoast Council. The most recent sampling was completed over the 2021–22 summer. The results of the monitoring program, including a detailed water quality report card for the Manning River, are available on the MidCoast Council website.

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.

Physical characteristics

Estuary type: Barrier river

Entrance
location 		Latitude (ºS) –31.88
Longitude (ºE) 152.7
Catchment area (km2) 8124.5
Estuary area (km2) 34.7
Estuary volume (ML) 96,258.5
Average depth (m) 3

Tidal exchange volume

Tidal exchange volume or prism data is available for this estuary. This tidal prism was measured in 1998. 

Tide state Flow
(106 m3)		 Local tidal
range (m)		 Sydney Harbour
tidal range (m)
Ebb flow 14.83
 1.31 1.57
Flood flow 10.08
 1.05
 1.45
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 catchment of the Manning River has seen significant land-use changes. Most of the mid and lower catchment have been cleared for beef and dairy production, and this accounts for around 40% of total land use.

Forest covers over half of the catchment, particularly in steeper areas of the upper catchment, but also interspersed with pastoral and rural-residential land in the lower catchment. The major towns in the Manning catchment are Taree and Wingham.

Water use

Find out about water use in the Manning River, including information about major water users, real-time flow data, and environmental and water sharing plans.

National and marine parks

Community involvement

  • Taree Landcare provides volunteers the opportunity to get involved in bush regeneration in the Taree area.
  • Manning Landcare is an umbrella landcare organisation that supports Landcare and environmental groups in the local area.