The aquatic community of the permanently flooded portion of a coastal plain pond with seasonally, and annually fluctuating water levels. These are shallow, groundwater-fed ponds that occur in kettle-holes or shallow depressions in the outwash plains south of the terminal moraines of Long Island, and New England. A series of coastal plain ponds are often hydrologically connected, either by groundwater, or sometimes by surface flow in a small coastal plain stream.

A wetland usually fed by rainwater or mineral-poor groundwater and dominated by short, evergreen shrubs and peat mosses. The surface of the peatland is usually hummocky, with shrubs more common on the hummocks and peat moss throughout. The water in the bog is usually nutrient-poor and acidic.