The new Jamestown Newport Ferry dock at Conanicut Marine Services in Jamestown, Rhode Island, needed to meet two important criteria: be creatively shaped to fit into an existing configuration and offer accessibility to disabled passengers. Owner Bill Munger turned to concrete doc systems provider SF Marina for a solution.
SF Marina designed and manufactured two custom SF 1800 solid cast concrete pontoons. Trapezoidal, the pontoons form an L-shape with a 70° angle.
The nine-metre side hosts the larger ferries that land stern first, while the 12-metre section is for smaller boats and water taxis.
The five-metres wide SF 1800 dock has a one-metre freeboard, making it easy for customers with wheelchairs to board. Plus, due to the sheer mass of the pontoons, they are stable enough that they do not shift under excessive weight nor from forces such as a large wake.
At Conanicut Marine Services, the SF 1800 pontoons are held in place with three pile guides along the side and one internally. Energy-absorbing cushion block technology and internal tensioning ensure the dock pontoons move smoothly as one unit with the 1.4-metre tide.
Munger had worked with SF Marina on two prior projects. Six years ago he installed a five- by 60-metre wave attenuator at Conanicut Marine Services and three years ago, he added one three- by 55-metre unit.
The installations were due to the area being exposed and subjected to inclement weather, but Munger claims the pontoons have held together nonetheless.
The SF Marina docks have been built to withstand weather extremes and severe daily use. These are built of steel-reinforced, thick-walled concrete with styrofoam cores for buoyancy.
The pontoons are also maintenance-free and can be built with integrated conduits for electric and water service.