They call them Cranberry Bogs as a whole, but the cranberries are actually grown in beds (Roland's Football Fields).
The beds are ditched around the outside of each bed (deep ditch). Each bed is separated by a dike with a road on it for the harvest/main. trucks, the beds have a floodgate at one end that is usually fed by a ditch of water on the other side of the dike.
The beds are constructed on the spruce/peat bog and usually nearby will be a large reservoir that they can pump out of to fill the ditches that fill the beds.
They fill the beds with approx 2-3 ft of water for harvest (Late Sept-Nov) because they use a big rotary beater (like a giant rototiller) to loosen the berries off of the vines and then the berries float to the surface of the water.
Then the grunt workers with waders on pull booms (floats) that span the entire width of bed toward the opposite end with the wind to help and yes the ditches are really deep and you can not see them in the cloudy water . Once the berries are corralled at one corner of the bed they are raked/floated up onto an elevator (like a hay elev.) with dump trucks under the other end, which haul them up to the drying/cleaning building where they are loaded onto semis and hauled to the big factory.
They drain the beds as soon as they have been harvested and actually haul dump truck loads of sand and put on the beds in the winter to firm up the beds and b/c crans prefer to grow in sandy well drained soil. (remember these are not wild crans, they are plantings).
Also crans are very touchy to frost and they have alarms set up with thermometer controls so the workers can wake up and turn on the big irrigation pumps as each bed is set up with sprinkler/irrigation system and they water the berries so they don't get frosted. This takes place until they are harvested and the irrigation pipes must be pulled prior to harvest (which was also one of my jobs).
I lived in Northern WI right next to a Cranberry Bog (Division of Oceanspray) and worked there as a seasonal harvest grunt for a few years!