Grass Island is a tidal marsh area in Greenwich Harbor, Connecticut. Part of the area is occupied by a boat marina and sewage plant.  Grass Island has a variety of uses. The Eastern portion remains in usage as a sewage treatment plant by the Town. A private Boat Club maintains a clubhouse, parking lot, boat storage and dock space in the southern section of the Island. Also, the Town has a boat yard and docks in the southwestern portion. The remainder is a managed conservation area.

CASHMAN was contracted to dredge and remove silt material as part of a maintenance dredging effort for the Town of Greenwich. 


  • CASHMAN removed 3,498 cubic yards of silt material that was processed in a scow with Portland Cement and transported to New Haven, CT where it was offloaded and placed in an approved upland facility. 
  • CASHMAN also removed an additional 21,530 cubic yards of silt material that was transported offshore to the Central Long Island Disposal Site. 
  • Equipment utilized for offshore disposal was the Wood II dredge, an SEI 2000 dump scow, and the Eddie Carroll dump scow. 
  • Equipment utilized for upland disposal was the Wood II dredge, the Michelle D. hopper, the SEI 2001 dump scow, and the SEI 2003 dump scow.
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Town of Greenwich, CT
$1.75 million
December 2008 - February 2009