Salinity in the Mid Salinity in the Mid-Atlantic Estuaries Figure 6.
Salinity is a measure of the total salt content in water.
Salinity measurements in estuarine waters range from less than 0.5 ppt in fresh water to 5 ppt in brackish water to 33 ppt in coastal ocean water. Bottom water salinity data for the summer is depicted in Figure 6. Oligohaline waters represent a small fraction of the estuarine area of the region. Mesohaline waters are dominant in Chesapeake Bay, while the Delaware Estuary and Delmarva coastal bays are mostly polyhaline waters.