International

Arc-shaped breakwater protects New Zealand Marina

Offering stunning panoramic views and unprecedented cruising opportunities, Waiheke Island Marina on Hauraki Gulf is New Zealand’s newest yachting destination. To shelter its 180 docks from fetching seas and passing island ferry wakes, but also to protect the area’s ecologically sensitive environment, marina owners partnered with industry leader SF Marina to install two uniquely curved floating concrete breakwaters.

Not only is Hauraki Gulf shallow, but the location is home to a colony of Little Penguins. The concern was that a traditional rock-pile breakwater would impact currents and the area’s delicate flora and fauna. Plus, the marina required a new office and parking lot, but the adjacent land was already developed. That’s why SF Marina floating concrete pontoons were the ideal solution.

Mirroring the island’s scalloped coastline, the two sections of the 460m breakwater are comprised of 23 individual 20m x 6m SFBW600 series floating concrete pontoons, six on the western section and 17 on the main portion. With a high level of buoyancy and unprecedented wave attenuating properties, SF Marina breakwaters have proven themselves all around the globe in overcoming extreme weather events.

Three breakwater sections on the western arc nearest to the shore are 2.4m in overall height, the remaining are 4m high; all have a 0.6m freeboard. The pontoons are connected via SF Marina’s patented coupling system that absorbs and distributes stress loads. Internal steel piles anchor the breakwater to the seabed and accommodate the marina’s 3.5m tide.

In keeping with the marina’s dedication to preserving its natural surroundings, the office and 2,100sqm car park are built on top of 27 SF1250 floating concrete pontoons. Like the breakwater, they’re engineered to be exceptionally stable and virtually unsinkable. Rainwater is channeled from these platforms and filtered to remove pollutants before being returned to the environment. Constructing atop an SF Marina floating concrete platform is not new — in Sweden, a two-story, 33-room hotel uses similar pontoons for its foundation.

The pontoons for Waiheke Island Marina were built in Port Whangarei, New Zealand by SF Marina’s manufacturing partner, Heron Marine, and towed 145km to Waiheke Island. SF Marina has offices and fabrication sites across the globe and a robust logistical network to ensure that no location is too remote for the benefits of its breakwater technology.

Located only 40 minutes from Auckland, Waiheke Island Marina offers local and visiting boaters modern, up-to-date amenities. A partner within the Waiheke Island community, the marina formed the Waiheke Marina Maritime Trust to help protect the local coastal environment and foster boating-related activities. The marina’s website is www.waihekeislandmarina.nz.