Project 1 | During rain events
The two projects saw Malmsbury Timbers use a variety of techniques to promote swamp rehabilitation and reduce erosion during heavy rainfall in the World Heritage listed Blue Mountains in NSW.
PROJECT 1 EROSION CONTROL
The objective of the first project was to slow the stormwater runoff velocity before entering the national park. This high-water velocity is created through the impermeable hard surfaces of urbanisation along the ridgelines in the blue mountains. 
Project 1 | Initial installation
Installation Steps
- A scalloped channel lined with jute matting was created.
- At intervals along the channel, Coir logs secured with timber stakes are positioned to act as road bumps for the free-flowing water.
- The channel directs the storm water runoff into a bioretention bay at the base of the slope, the bioretention bay allows the runoff to soak into the ground reducing the erosion affect.
Project 2 | Initial installation & one year after installation
PROJECT 2 SWAMP REHABILITATION
For the second project, the objective is to rehydrate a traditional Blue Mountain swamp area. Malmsbury Timbers did this by retaining water runoff on the sandstone plateau. Creating a natural retaining wall combined with low subsurface permeability (sandstone plateau) creates a habitat that is ideal for the Blue Mountain swamp. 
Project 2 | Two years after installation
Installation Steps
- A wall of coir logs wrapped in jute matting is dug into the ground at the low point of the sloping ground. As rain events occur, water runs down the valley and starts to back up once it hits the Coir log structure. Water seepage through the wall is at a very low rate, allowing the water to build up in the valley and rehydrate the subsoil thus building up the ground hydrology.
- In time the retained moisture in the soil enables native swamp vegetation to grow. In the case of this project, native grasses grew back very successfully over a two-year period.
To discover how Malmsbury Timbers can help with your next bush regeneration project, contact them via the links below.
