Concept Design Option 1: Offshore Breakwater with Gaps

Offshore Breakwaters provide protection through limiting wave action on the shoreline. They are constructed on the lake bed and do not attach to the shoreline. Waves lose intensity when they break against the structure, which reduces the impacts to the shoreline.

Some of the critical design elements of this option include:

  • Using larger stone (2-4 tonne armourstone) that would be visible above the water line
  • Moving shoreline protection away from the shore to allow for some amount of natural sedimentation
  • Gaps allow for increased circulation between breakwaters, which promotes longshore movement of sediment

Key Benefits

Offshore emergent structures providing wave protection

Increases circulation, allows for potential sediment movement

High level of protection while still allowing for water movement and some natural erosion

Offshore Breakwater Cross-section. W.F. Baird, 2022



  • Maintaining a natural shoreline
  • Providing calm water habitat for aquatic species nearshore
  • Design flexibility to bring down costs
  • Increasing shoreline usability



  • Complex installation and maintenance
  • Visible from the shoreline
  • Sourcing the correct material could be expensive due to size

This option is currently preferred for Reach 3 and Reach 9, and has a rough cost of $32,000/m.