01 Nov Daryl Albertson
Senior Wetlands and Rivers Conservation Officer in the North West Region of NSW, Office of Environment and Heritage.
The Gwydir Wetlands are a terminal wetland system, west of Moree in northern New South Wales. It provides important migratory and waterbird habitats and are recognised as a Ramsar wetlands.
The construction of Copeton Dam in the late 1970s, altered the downstream water regime. At the same time, channels were cut across the floodplain. These actions drove a general floodplain and wetland drying. By 2008, these wetlands existed at only 15% of their former extent.
In 2007-2009, a project within the NSW Rivers Environmental Restoration Program, installed a water supply pipeline to replace the network of open channels. A 240 kilometre pipeline and infrastructure was installed at a cost of $2.9 million. The pipeline then provided the opportunity for NSW Office of Environment & Heritage to begin the process of wetlands restoration.
Additional funds were invested to close the channels, which then halted wetland draining and promoted natural flooding patterns.
In planning the path for restoration, current mapping data sets and advice from local landowners assisted in understanding the system.
However, the limiting factor was the ability to determine what the wetlands looked like prior to the 1970s and the connection of water flows to historic and current wetland habitats.
The timely discovery of aerial photos, taken by survey biplane in 1936, provided a window into the past and enabled satellite imagery and GIS platforms to be employed. A clearer picture then emerged of where to undertake on-ground works that would assist the watercourse to rejuvenate and in time self-repair.
Five years since completion, old flow paths to historic and key habitats have been reconnected and improved flooding extent and duration have been achieved. What was a restoration target of 3000 hectares is closer to 5000 hectares today, supporting the notion that the environment will self-repair, if given the chance.