An estuary is a partially enclosed coastal body of brackish water with one or more rivers or . The denser seawater moves landward along the bottom of the estuary , forming a wedge-shaped layer that is thinner as it approaches land.
MANY estuaries are sufficiently deep relative to their maximum fetch that even in severe storms the bottom remains undisturbed by.
Organic particulates draining from the land tend to be sedimented out in the estuary. Their breakdown on the often muddy bottoms tends to recycle needed.
To compensate for the entrained salt water, there is a slow movement of the salt water up the estuary at depth. Because bottom waters are rich in nutrients.