Eerste River

The Eerste River catchment covers the eastern part of the Cape Flats lying to the west of the Hottentots Holland Mountains and south of the Tygerberg where the Kuils River tributary rises east of Kanonkop.

The estuary is at the eastern end of a large calcrete dune, and is part of the boundary of the Helderberg Marine Protected Area.

In its natural state the estuary was a small temporarily open system with little tidal flow.

The state of the mouth was controlled by river flow, and under natural conditions, seawater intrusion would maintain an estuarine ecology.

When the mouth closed, the river would back up past the Kramat to Zandvliet farm.