urban-projects

South Lismore Flood Diversion Channel

  • Location - Lismore, NSW
  • Value - $4.3 million
  • Start date - September 2019
  • Completion date - July 2020
  • Client - Lismore City Council

The Lismore Flood Diversion Channel involved the excavation and placement of roughly 410,000m3 of material including, stripping and re-spreading of topsoil, revegetation works and the removal of existing Sewer Rising Mains.

The Lismore City Council designed the flood diversion channel to provide flood mitigation to the city. Flood modelling undertaken in 2016 suggest the Flood Diversion Channel will reduce peak water levels in the CBD, North Lismore and South Lismore by as much as 100mm during a 1 in 100 year flood event.

The Diversion Channel will achieve this by:

  • Providing for a more even flow of floodwaters through the cross-section of the floodway
  • Reduce floodwater from Leycester Creek
  • Increase the cross-sectional area equivalent to the areas which abut the channel being excavated.

scope of works

  • Excavate, haul and place roughly 410,000 cubic metres of extracted fill into three fill sites
  • Traffic control including full long-term closure (12 weeks) of Caniaba Street
  • Environmental controls including flora and fauna management and erosion and sediment control
  • Clearing and grubbing of each extraction cell
  • Stripping, stockpiling and re-spreading of topsoil, including hydromulching
  • Removal and disposal of five redundant Sewer Rising Main lines

photos

Brookhaven (various stages)

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