Aboiteau farming on reclaimed marshland is a labor-intensive method in which earthen dykes are constructed to stop high tides from inundating marshland. A wooden sluice or aboiteau (plural aboiteaux) is then built into the dyke, with a hinged door (clapper valve) that swings open at low tide to allow fresh water to drain from the farmland but swings shut at high tide to prevent salt water from inundating the fields.