The pictures here are just simple schematics to demonstrate the principles involved. Docks can be fabricated to various different lengths by simply adding floating or moored segments between the moored segment and the grounded segment.

This floating dock is constructed from solid-plastic PrimoPlank, including the under-frame. The floats are also thick-walled polyethylene plastic barrels. Polyethylene plastic actually has 50% more traction when wet than when dry, so the platform never gets slippery for the pedestrian. The solid plastic will never get mildew. Moss can be hosed off using a scrub brush. Barnacles and sea salt will not affect the strength of the post nor the perimeter bumpers and will scrape off easily with a paint-scraper.

The key element is the octagonal sleeve made from 2x6 board that straddles the solid-plastic 5½ -inch round post. This allows the moored dock to rise and fall with the water level very smoothly because plastic sliding on plastic is almost frictionless. Further, the continual shifting of the platform up and down along the posts keeps the active segments of the posts clean automatically.

Post pairs can be connected with a 1½ -inch round handrail that pierces the posts. This is secured with ball-caps on each end. This handrail can be extended through more than just one pair of posts when longer docks are made from similar, connecting platform segments.

On the otherhand, where the handrail is not desired, the 1½ -inch round can just be provided in a 7-inch segment that pierces the top of the post and is fastened with two solid-plastic ball-ends, one on each side of the post. This arrangement prevents the floating dock from rising above its mooring posts and being carried away in a flood or an unusually high tide or swell. The shape of the ball-ends provides a smooth end-cap that won't bind clothing but will easily anchor a sea-knot.

Each plastic post is anchored into the ground under water using a 24-inch galvanized steel screw-type ground anchor that's fastened to its base. The driving machine is kept entirely above water on a floating platform. After anchoring the post, a precast concrete column is slipped around the post and sunk to ground level. Wet concrete is then funneled into the sleeve for a permanently secure anchor.