The health of the Manning River estuary is in fairly good condition according to the State of the Manning Report Card.
The report card summarises the results of a water quality monitoring program undertaken in the Manning River estuary during 2013/14.
Receiving an overall grade of B has placed the Manning River in the top half of all estuaries in NSW in terms of ecological health.
During the preparation of Council’s Environmental Action Plan, the community identified the health of the river as one of the most important environmental issues in the Manning Valley. However, in order to effectively manage and protect the river, we need to first have an understanding of its health and condition. A greater understanding of the health of the estuary will assist us and other land managers to identify and target areas where further investigation and action is required.
The report card has revealed that while overall the estuary is relatively healthy, bouts of poor water quality were experienced in the mid to upper zones of the estuary, particularly following rainfall. Poor water quality can be characterised by high turbidity levels and excessive algae growth. Turbidity in the Manning occurs as a result of sediment laden runoff from areas where vegetation has been removed and the soil is exposed, and from gravel roads and eroding riverbanks; whereas high levels of algae are caused by stormwater runoff that contains nutrients from urban areas and farmland, and from cattle accessing the waterway.
We have recently undertaken a number of projects to address poor water quality in the Manning River including riverbank stabilisation works at Glenthorne and Wingham, where the banks have been revegetated with native plants and rock fillets have been constructed to protect the banks from erosion and to allow the re-establishment of mangroves.
The health of the Manning River is such a high priority for the local community, 50% of all funding raised through the environmental levy has been allocated to projects that achieve improvements in water quality and estuarine health. This funding will enable us to implement many of the actions contained within our Estuary Management Plan including the continuation of the water quality monitoring program for the Manning River. This is the first year of what is intended to be a long-term approach to tracking the health of the estuary and identifying any obvious trends.
The project was made possible with matching funding provided through the NSW Office of Environment and Heritage’s Estuary Management Program.