This is BIG! Twin CDS® 3030’s for Dubbo Regional Council

Thank you and congratulations Dubbo Regional Council on your choice of proven twin Rocla CDS® P3030 recently installed to protect the Macquarie River and waterways like no other GPT.

Safely and capably installed by Whittaker Civil with design and project management by our long-standing partner Optimal Stormwater.

With a heritage of the largest installed capacity of GPTs, Rocla partners with forward thinking asset owners, consultants and customers – like Dubbo Regional Council, Optimal and Whittaker – to develop effective, proven and reliable stormwater solutions.

Care of Optimal and site supervisor Peter Warnock here are the facts about this BIG project:

  • 300 hectre catchment area
  • ~2,000m3 of spoil was excavated to a depth of 12m
  • The twin CDS® units can reliably treat up to 3,750L litres per second of stormwater
  • Each CDS® P3030 contains 66 tonnes of pre-cast concrete including a sump extension to hold 20m3 of pollutants delivering a combined project storage capacity of 40m3
  • Rocla’s unique CDS screen technology will treat up to 95% of gross pollutants, down to 1mm in size. It is prefabricated and assembled on site with no welding required.
  • To accept overland flows Optimal Stormwater included an energy dissipating apron surrounding a new “Letter Box” grate on the diversion chamber.
  • A compacted crushed granite hard stand was constructed for cleaning and maintenance access.

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