First large-scale gully project a success

The Mt Wickham site was selected as the LDC project’s first large-scale gully remediation site.

The gully catchment treatment size was 3.03 ha and the control site size was 14.14 ha.

Treatment

The area underwent significant earthworks with tunnels excavated and the area reshaped and compacted with a bulldozer to a gradually sloping shape to reduce the velocity of water moving off the site.  

A series of rock chutes were constructed to manage water flow, and diversion banks were installed to divert runoff.

Revegetation included 538kg seed planted, including deep-rooted legumes, canopy species, pasture grasses, legumes and cover crops.

Results

Remediation was carried out  in 2018 allowing two wet seasons of treatment data to be collected. 

A number of statistically significant positive indicators are demonstrating that the Mt Wickham treatment is effective, independent of natural climate variability. 

The cover and biomass of the hillslope and gully walls have significantly improved, as well as the water quality and total suspended sediment concentrations. 

While land condition overall is showing an improvement from before treatment, it does remain fragile and will require careful management and ongoing monitoring. 

The total suspended sediment (TSS) levels at the control site and the treatment site are dropping from the baseline measurement, one year after treatment and two years after treatment.

Data collected on the adoption and effectiveness of landscape remediation techniques and farm management practices is used in the annual Reef Water quality Protection Plan report card as well as to enhance the catchment models. 

This is facilitated through the Paddock to Reef integrated monitoring, modelling and reporting program.

*Information sourced from the CSIRO report.