Definition

Content prepared by AT Forbes

In the southern African context the following is a generally accepted definition of an estuary. “It is a partially enclosed, coastal body of water which is either permanently or periodically open to the sea and within which, there is a measurable variation of salinity due to the mixture of sea water with fresh water derived from land drainage” (Day 1980). Such water bodies are therefore linked to a river, stream or other freshwater input at one and to the sea at the other. The absence of a recognizable source of freshwater, such as occurs in Langebaan Lagoon, would exclude any such systems from inclusion in this section although it displays many of the typical estuarine characteristics.