Pile Installation Begins
Revised August 25, 2009
(Original Post August 19, 2009)
Installation of 321 new piles into the lake bed has begun and will continue for approximately six months. Ultimately, these piles will support 4,000 feet of new interceptor sewer pipe that will be hoisted onto the piles during the lake draw down that starts in September 2010.
Pile work started in the west end of the lake and will generally move east. Given the geology of the lake bed, most piles can be vibrated into place to the depths needed for seismic strength. A vibratory hammer will be used as much as possible to minimize the need for more conventional and noisy pile driving equipment. When the construction crew encounters large boulders or when the pile needs to be driven into bedrock, a traditional pile driver will be used and neighbors can expect increased volumes of intermittent noise at those times.After a handful of piles are installed, the contractor will cut them off well below the lake surface at the required height to support the new pipeline. The contractor will repeat this process until all piles are installed. Any piles temporarily protruding from the lake will be protected by barges or clearly marked so boaters can avoid them.
Detours may be required for boaters in the shallower west end of the lake, but navigation ways will be maintained during the summer season and into the fall. Navigation in Blue Heron Canal may be limited mid-October to November.
Most of the piles will be installed in the west end of the lake near the southern shoreline. Pile installation in Blue Heron Canal will occur toward the end of October and will extend as far as South Shore Blvd. In December and January, pile installation will continue in other areas, including near Twin Points, Diamond Head, Springbrook Creek, Lost Dog Creek and Half Moon Bay.