Water erosion control after fire – Western Australia

Page last updated: Wednesday, 22 November 2023 - 10:40am

Fire removes organic ground cover, and the risk of water erosion is greatly increased. Summer thunderstorms or early autumn storms (before adequate vegetative groundcover develops) can result in serious erosion on burnt areas.

The Department of Primary Industries and Regional Development provides this information to help land managers to reduce the risks of water erosion.

First steps after a fire

  • Minimise vehicle and livestock traffic on bare ground: detached soil is much more susceptible to erosion.
  • Check and repair any upslope surface water management structures. If you don't have them, this is a good time to plan where they should go.
  • Protect water resources from contamination with paddock residues and silt.

Prevent silt and other material being washed into dams and other water resources

 Temporary sediment fences are a cheap and effective way to reduce contamination of those water resources. The temporary sediment fences can be removed when paddock ground cover has established after the break of season.

See How to build sediment fences (an Agriculture Victoria YouTube video) and download the Building a sediment fence PDF from Agriculture Victoria .

We recommend that you prevent future contamination by constructing or maintaining silt traps, and using fenced, roaded catchments where possible.

At the break of season

In the following year

Identify any areas that had water erosion following the fire, and plan and build water erosion control earthworks.

Areas at risk

Areas at greatest risk from water erosion following a fire include:

  • long, steep slopes
  • access tracks and rocky areas
  • changes of grade in creeklines
  • along access tracks where slopes are traversed
  • near culverts, where water is concentrated
  • anywhere there is existing or past erosion. 

Problems from water erosion after a fire

These problems are mostly the same as for any water erosion:

Being prepared for fire

We recommend that dealing with water erosion after a fire is part of a farm plan that includes fire and whole-farm water management.

For more information see bushfire survival plans for landholders