Categories: /30 Dec 2011

Fisher Island Community Association

Fisher Island, Florida

Engineer of Record
Coastal Systems International, Inc.

Date of Completion
June 2004

Contract Bond
$1.8 million

Fisher Island is a 216 acre luxury resort island which is separated from Miami Beach by the ocean inlet of Government Cut. To provide transportation to the island, the Community operates four 120 foot by 46 foot passenger / car ferries. The ferries depart and land on average every 10 to 15 minutes, 24 hours a day, 7 days a week. Departing simultaneously from the MacArthur Causeway on Miami Beach and from the Ferry Landing on Fisher Island, the ferries make the trip in approximately eight minutes. Upon arrival at each landing, the ferry exerts enormous thrust as the vessel slows, coming to a complete stop with the aid of the fender system. The ferry holds position by pushing against the fenders during the unloading and loading process.

After years of this constant and aggressive use, the ferry landing fender system required replacement and design modification. The new design required the installation of four 72 inch diameter epoxy coated steel pipes, 80 feet in length and driven to a depth of 60 feet below the bay bottom. The pipe supports large timber sections which in turn support massive sections of solid rubber fender material. Held in perfect vertical alignment by a specially fabricated steel jig system designed by Shoreline Foundation, each pipe was lifted into position and lowered until it came into contact with the bay bottom. The pipe was gripped by a large crane-supported vibratory hydraulic hammer which drove it into the bay bottom.

Managing the working conditions on site presented some significant challenges. The substrate into which the pipe was driven proved to be exceptionally hard and driving each pipe was a slow and tedious process. Working in such close proximity to Government Cut contributed to the difficult working conditions due to the large volume of boats and the strong tidal currents. However the greatest concern was the close proximity of the project site to the subterranean 52 inch wastewater force main. Compromising the integrity of this force main was a not an option.

The new landing dock absorbs all of the abuse the Fisher Island ferries can deliver and demonstrates the steadfast durability of a Shoreline Foundation project.