A few weeks ago I found myself in the midst of a conversation about the different types of brackish water formations. I came away more confused than when we started.

I hope my research will clear some things up for you.

What is brackish water, you may ask. “Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater.”

An estuary is an “area where a freshwater river or stream meets the ocean. In estuaries, the salty ocean mixes with a freshwater river, resulting in brackish water. Brackish water is somewhat salty, but not as salty as the ocean. An estuary may also be called a bay, lagoon, sound, or slough.” “

A fjord is a “deep, narrow and elongated sea or lakedrain, with steep land on three sides. The opening toward the sea is called the mouth of the fjord, and is often shallow. The fjord’s inner part is called the sea bottom. If the geological formation is wider than it is long, it is not a fjord.”

A sound is “a relatively narrow passage of water between the mainland and an island. It’s also an inlet, bay or recessed portion of the ocean.”

A bay is a “body of water partially surrounded by land. A bay is usually smaller and less enclosed than a gulf. The mouth of the bay, where meets the ocean or lake, is typically wider than that of a gulf.”

A gulf is a “portion of the ocean that penetrates land. Gulfs vary greatly in size, shape, and depth. They are generally larger and more deeply indented than bays. Like bays, they often make excellent harbors.”

“Lakes are almost always landlocked, while lagoons connect to a bigger body of water. Lagoons are usually shallower than lakes. Lagoons have varying salinities, whereas lakes are either freshwater or saltwater. Animals in lagoons can tolerate varying brackish conditions, while animals near lakes need freshwater.”

Sloughs are “ecologically important as they are a part of an endangered environment; wetlands. They act as a buffer from land to sea and act as an active part of the estuary system where freshwater flows from creeks and runoff from the land mix with salty ocean water transported by tides.”