Grass Island Marina is one of Greenwich's four public marinas open to residents with a valid permits, from April 15th through November 15th each year. The marina has about 150 slips for boats up to 23 feet long with beam widths of up to nine feet, and a limited number of slips for longer boats. Out-water moorings can accommodate 75 36-foot boats with up to five-foot drafts.
Visitors to Grass Island can tie up vessels free of charge during the day, and overnight for a charge determined by boat size; call the harbormaster for details. Winter storage for boats is available at all marinas from September 1st through June 1st. Limited rack storage for kayaks and canoes is also available. Further information on moorings and required permits is available on the Department of Parks and Recreation website.