Far West Rangelands Rehydration Alliance
Landscape Erosion Filters
Construction of soft filters to complement ponding works to rehydrate vast areas of the rangelands
Issue:
Fast moving water from higher rainfall events over time has eroded the topsoil and caused gullies. Graded roads, wheel tracks, animal tracks and fence lines on the fragile soils of the Rangelands in far west NSW have provided the fast moving water with these paths of least resistance to follow and reducing natural flood out distribution.
One comment at the baseline project assessment stage:
‘The original cause of the problem is historical overgrazing going back as far as Kidman times as well as the historic ‘stock route’ which traversed the area. Previous generations have attempted rehabilitation. Most notably, in the 1980’s ‘Soil Conservation NSW’ completed contour furrowing. There is a need for a new solution which allows water penetration and rehydration by ponding water for longer periods.’
Picture shows tape at 50 mm. Example of the beginning of gully erosion. Arrow at head of creeping gully erosion of topsoil.
With the assistance of funding sourced from the NSW Environmental Trust, the installation of 16 erosion filter sites at gully heads in the White Cliffs, Packsaddle and Broken Hill areas were established. Knowledge gained by working with Ecosystem Management Understanding (E.M.U) and the Western Local Land Services Rangeland Rehabilitation Senior Officer, was key to achieving functional and practical “erosion filters” specifically made for the job that they were required to do. Filters were constructed of a variety of materials including a mixture of steel and star posts, weld mesh, chicken wire, coir logs, old wool and rocks.
Pictured are examples of different filters.
The Far West Rangeland Rehydration Alliance (FWRRA) represents 20 stations in the Far West of NSW. They have actively been involved in protecting, restoring and rehabilitating valuable rangeland ecosystems.
An important part of rangeland rehydration and ‘RAIN READY’ techniques is having infrastructure in place to take advantage of every rainfall event. The construction and installation of strategically placed erosion filters will provide a structure that will slow the movement of the water down at the gully head, this will complement and accelerate rehabilitation recovery time. The installation of filters at gully heads to slow the water entering the water system is a relatively new concept for rehabilitating the rangelands.
Early results from information gathered while setting up photo monitoring points have shown positive results.
The initiative of the FWRRA to install the erosion filters at the gully heads shows that the members of the Alliance have more than their personal interests at heart. These techniques are important for resilient agriculture and healthy biodiversity.
The value of these filters will be demonstrated as seasons dry out and herbage declines. This is a very important initiative for drought buffering and rehabilitating the rangeland landscapes.
What worked?
Early signs are showing these filters will help to combat erosion as well as increase vegetation.
Some landholders have invested a lot of time experimenting with different filters to find ones that are best suited to their country, and have continued to construct more filters than were required by this project.
As with all earthworks, periodic inspections, especially after rain events, are required to maintain efficiency.
Pictures taken early May 2025: increased vegetation matter build up and some growth in veg after a rain event.
What didn’t?
Some filters did not work as expected and so additional material options were added to improve the function of the filters. Some sites were moved from the original located position.
Unfortunately, some sites are still waiting for rain and are yet to see any results.
Pictures show the difference between where the mesh is secured to the ground eventuating in veg build up and growth in comparison to where the water has rushed under the unsecured mesh and has enabled the rushing water to reduce soil height.
This project has been assisted by the NSW Government through its Environmental Trust.
