Mt Wickham Gully Rehabilitation Project Phases 1 and 2

Specifications

• Client: North Queensland Dry Tropics
• 
• Scope:

  The Queensland Government is funding two Major Integrated Projects in North Queensland targeted at realising enduring change in land use practices to reduce nutient, sediment and pesticide loads on major waterways and improve water quality of the Great Barrier Reef Lagoon. Under the the North Queensland Dry Tropics Major Integrated Project "Landholders Driving Change " a large-scale pilot gully rehabilitation project is being trialled at Mt Wickham, 38km WNW of Collinsville.

  The Mt Wickham site expresses a number of erosion processes and features. 

  Verterra partnered with Alluvium to successfuly deliver Phase 1 construction and rehabilitation works in late 2018.  Phase 2 construction and rehabilitation works undertaken in October and November 2019 are nearing completion.

  Alluvium provided hydrological analysis for design of erosion control structures, and cut and fill analysis for required earthworks.

  Verterra completed a detailed site characterisation to inform development of the functional rehabilitation plan, in addition to managing the construction earthworks and rehabilitation works: 

  Landform of major erosion areas; 

  Amendment of scalded, dispersive catchment areas; 

  Construction of graded control structures; and

  Revegetation of the site to achieve a stable, resilient landform.

  Phase 1

   Basin 1a Before and After

  

  Phase 2

  

  

• Challenge:

  Historic grazing practices, in combination with fragile, dispersive soils have led to the development of large scale erosion gullies throughout the Burdekin catchment.  Export of this fine sediment to surface waters flowing into the Great Barrier Reef lagoon, can lead to stress of the Great Barrier Reef ecosystem, particularly inshore reefs and seagrass beds.  The bulk of fine sediment delivered from the Burdekin River basin to the GBR is derived from a small proportion of the basin area, primarily within the Broken-Bowen-Bogie (BBB) catchments (43%) and Upper Burdekin catchments (27%) with a large proportion of this load from grazing lands.  

  

• Solution:

  Building on ground-breaking work in dispersive soil rehabilitation undertaken through an Australian Coal Association Research Program (ACARP) research project, Verterra undertook a spatial site characterisation using Electromagnetic Surveying (EM) and UAV-based multispectral sureveys of target erosion gullies, followed by targeted soil sampling.

  The resulting data underpinned development of a conceptual model or erosion processes for the site, and design of interventions and soil amendments for each landscape component.

  Following completion of Phase 1, the initial gully rehabilitation works were tested and held up well following a 350mm rain event over a 48 hour period (February 2019). 

  

  Also Visit the Landholders Driving Change update webpage LDC Mt Wickham Update:

   

• Capabilities:
  • Soil Science
  • Erosion and Sediment Control
  • Gully Rehabilitation
• Location: Queensland
• Year: 2017 - 2020