work in the Barnard River catchment
Since 2011 when the catchment of the Barnard River was identified as a significant source of sediment and nutrient pollution in the Manning River, MidCoast Water has undertaken a variety of works to improve the situation. The largest projects are at Glen Almond, near Nundle; and on unsealed public roads within the flood zone of the upper Barnard River and its tributaries.
In July 2011, MidCoast Water purchased a property in the headwaters of the Manning Catchment. It is located on the upper Barnard River at Barry, 80 km north west of Gloucester. The 1011 hectares are in steep, rugged terrain with highly erodible soils. At the time of aquisition there were a number of problems which were contributing to the high suspended sediment load in the Barnard River, so to poor water quality downstream in the Manning. These included unvegetated, eroding river banks with unrestricted cattle access; a large amount of gully erosion; pastures with poor ground cover; failing dams; and eroding dirt roads and tracks across the property.
Upon settlement, MidCoast Water started to address these problems in collaboration with neighbouring properties and government bodies. Plans have also been put in place to conserve biodiversity on the site by doing a Property Vegetation Plan through the Hunter Local Land Services. Land has also been put aside for carbon sequestration through native reforestation as part of MidCoast Water's efforts to become carbon neutral.
River Bank Stabilisation
Riparian fencing was completed along the Barnard River on Glen Almond and adjacent properties, and on the three major gullies connected to it in late 2011. An off stream watering system was installed to complete the removal of unrestricted cattle access, which will allow the banks to revegetate. A variety of native plants indigenous to the area were planted in spring. The project was completed with funding partially through the Hunter Local Land Services.
Clockwise from top left: stock-proof fencing of an eroding gully; staking new riparian plantings; a solar
pump for the stock watering system; a new off-stream stock watering point.
The above style of river restoration works are known as 'soft engineering' - allowing the natural river processes to operate with minimal interferance. Two types of 'hard engineering' works have also been carried out on actively eroding sites. This refers to hard structures being put in place for bank protection, and in some cases mechanically reshaping the bank. Rock fillets have been installed (below left), and in some cases existing dead wood has been realigned and pinned into the bank (below right), offering a natural style of bank stabilisation.
Property Vegetation Plan
MidCoast Water has prepared a Property Vegetation Plan (PVP) in collaboration with the Hunter-Central Rivers Catchment Management Authority, with funding through Catchment Action NSW and the Australian Government's Caring for our Country. It covers approximately 600 hectares and five ecological communities. Descriptions of these are available in the Glen Almond Vegetation Management Plan prepared by RPS. It incorporates the highest, steepest parts of the property as well as the Barnard River riparian area.
The PVP is a voluntary contract with the State Government, and is legally binding under the Native Vegetation Act 2003. It directs that MidCoast Water protects biodiversity in the area defined in the PVP through mechanisms such as:
- not allowing clearing, or grazing by domestic stock
- replanting/seeding where natural regeneration does not occur
- controlling weeds and feral animals
- leaving all rocks and dead timber on site, and allowing natural water flow
- undertaking erosion control where necessary, including on tracks
Unsealed public roads
Several problematic road sites were identified in the Tamworth and Upper Hunter Local Government Areas, where dirt was running directly from the road to the river. MidCoast Water worked with these Councils, again with funding assistance from the Catchment Management Authority, to stabilise these erosion points. Shown below are a site where a sealed causeway was installed (top), and a site where the road is so close to the Barnard River that the river cuts into the road, and innundates it in floods (bottom). Before (left) and after (right) photos are shown.