Professionally designed by experienced engineers to give the best attenuation performance in their category and offer extreme strength and long maintenance-free service life, the all-new Marinetek KH-series breakwater units are industry giants. Top of the range 6300-series units weighing 86 tons apiece and with 2 x 116 ton flexible connection capacity have recently been manufactured by Marinetek in Croatia and shipped to Saguenay, Quebec to create the biggest Marinetek breakwater in Canada.
The KH-series is the result of nearly 12 months’ R&D including extensive research, design and engineering, and tank tests conducted by VTT Technical Research Centre in Finland, one of the leading companies of its kind in Europe. VTT operates under a mandate from the Ministry of Employment and the Economy and has been offering top-level research and science-based results to private and public sector companies for 75 years. Marinetek, with 35 years’ experience of its founders in the design and production of floating breakwaters, is no stranger in the field but the VTT tested KH-series takes its portfolio to new levels of excellence.
The City of Saguenay set a demanding brief when approaching Marinetek North America in September 2017. City and engineering firms were looking for a floating breakwater system that could remain in the water during the harsh conditions of icy winters and offer protection from aggressive waves and tides during the summer operating season. Daily tides can stretch up to 6.9m (23 feet); water depths vary from 6 to 24m (20 to 80 feet); and waves can reach 2.3m (7.5 feet) high. In addition, the installation has to sit in brackish water with up to a metre of thick ice, and withstand winds up to 34 m/s (75 mph). 86-ton floating breakwater units, measuring 6m (19.6 feet) wide x 20m (65.6 feet) long x 2.4m (7.8 feet) high, were built for the project, which was designed by Marinetek from start to finish. “One of the main challenges was to anchor these immense floating breakwaters in deep water with the large tides,” explained Richard Murray, Marinetek North America Managing Director and Head Engineer. “After reviewing all the design criteria and site conditions, we decided to use heavy duty steel chain with massive anchor blocks on the longer section and large steel vertical H-beams along the seawall for the shorter section.”
The breakwater units were shipped from Marinetek’s Croatian factory to Canada, towed to the project site and installed in August 2018 using 80 concrete sinkers and chains. Four vertical steel H-beams were secured to the seawall.
Removing large, heavy breakwater units from the water in winter is a process to be avoided and the City of Saguenay is delighted and relieved to have a high performance floating attenuator that can stay in position whatever the weather. A spokesperson confirmed that the City is very pleased with the system and described the new breakwater as “beautiful and attenuating the waves wonderfully.”
“This was a tremendous project to premier our KH-series,” Murray noted. “We feel very proud of the quality and strength of these massive units and their ability to offer high levels of protection in a very changeable and aggressive environment.”