Patterson Britton is currently undertaking the detailed design and documentation for the proposed $100M Shell Cove Boatharbour. Patterson Britton is undertaking all the maritime and coastal aspects of the project including:

• an offshore breakwater
  
• groyne
  
• excavation and management of some 650,000m3 of acid sulfate soils
  
• foreshore treatment
  
• boardwalk
  
• wharf
  
• boat ramp
  
• 350 berth marina
  
• harbour flushing system

Patterson Britton is responsible for all investigation, design development, detailed design, environmental assessment, Section 96 modification of existing conditions of consent, Environmental Management Plans, tender documentation, construction supervision and management of 15 sub-consultants.

For creation of the Boatharbour, 1.3 million cubic metres of material is to be dredged/excavated, transported and disposed of. The material includes a range of material types from soft muds to rock, and includes acid generating material. Disposal options have included unconfined sea disposal, onsite disposal by means of over-excavation and reburial, and offsite disposal to licenced landfills.

Innovative approaches to the design of the Boatharbour have allowed a reduction in dredging/excavation volumes from 2.2 to 1.3 million cubic metres, minimisation of the need to excavate acid generating material, and the ability to beneficially reuse over-excavated rock in breakwater construction. Scaled physical modelling of the entrance works was carried out to optimise armour design of the breakwater and groyne, and to assess wave climate and seabed stability. These approaches alone have resulted in savings in excess of $20M.