False Bay

Bay of the Atlantic Ocean at South Africa

False Bay (Afrikaans: Valsbaai) is a body of water in the Atlantic Ocean between the mountainous Cape Peninsula and the Hottentots Holland Mountains in the extreme south west of South Africa. The mouth of the bay faces south and is demarcated by Cape Point to the west and Cape Hangklip to the east. The north side of the bay is the low lying Cape Flats, and the east side is the foot of the Hottentots Holland Mountains to Cape Hangklip which is at nearly the same latitude as Cape Point. In plan the bay is approximately square, being roughly the same extent from north to south as east to west, with the southern side open to the ocean. The seabed slopes gradually down from north to south, and is mostly fairly flat unconsolidated sediments. Much of the bay is off the coast of the City of Cape Town, and it includes part of the Table Mountain National Park Marine Protected Area and the whole of the Helderberg Marine Protected Area. The name "False Bay" was applied at least three hundred years ago by sailors returning from the east who confused Cape Point and Cape Hangklip, which are somewhat similar in profile when approached from the southeast. False Bay is at the extreme western end of the inshore Agulhas marine ecoregion which extends from Cape Point to the Mbashe river over the continental shelf, in the overlap zone between Cape Agulhas and Cape Point where the warm Agulhas Current and the cooler South Atlantic waters mix. The continental shelf is at its widest in this ecoregion, extending up to offshore on the Agulhas Bank, but is considerably narrower off False Bay. This ecoregion has the highest number of South African marine endemics, and is a breeding area for many species. The transition between the Agulhas ecoregion and the cooler Benguela ecoregion is at Cape Point, on the western boundary of False Bay. False Bay also contains South Africa's largest naval base at Simon's Town (historically a base for the Royal Navy), and small fishing harbours at Kalk Bay and Gordon's Bay.

The western side is bordered by the Cape Peninsula, and this stretch of coastline includes the smaller Smitswinkel Bay, Simon's Bay and Fish Hoek Bay. At Muizenberg the coastline becomes relatively low and sandy and curves east across the southern boundary of the Cape Flats to Gordon's Bay to form the northern boundary of False Bay. From Gordon's Bay the coastline swings roughly south, and zig zags its way along the foot of the Hottentots Holland Mountains to Cape Hangklip which is at nearly the same latitude as Cape Point. The highest peak on this side is Kogelberg at
Suburbs of Cape Town stretch right across the Cape Flats from Simon's Town halfway down the Cape Peninsula to the north eastern corner at Gordon's Bay. There are also two small towns of the Overberg region on the east coast of the bay, Rooiels and Pringle Bay.

The famous naval base of Simon's Town is in Simon's Bay, about halfway down the length of the False Bay coast of the Cape Peninsula. During the Second World War many heavy guns were mounted in concrete bunkers at various points along the mountainous shores of False Bay in order to deter attacks on Simon's Town. The firepower and defensive situation of these weapons were formidable and no attack was ever mounted. Although some of the guns were removed decades ago, a few large guns are still emplaced on the hillsides near the Redhill road. Lower North battery at the bottom of Redhill road is used for naval gunnery training and has a few examples of currently used weapon systems for this purpose.

Although urban development of the coast is intense along some parts of False Bay, much of the shoreline remains relatively wild and unspoiled. The bulk of the development is residential; there is little heavy industry. There are a few exceptions, however: one of the largest dynamite factories in the world used to lie near the beach in a sparsely inhabited region towards the eastern end of the bay. The nitroglycerine plant at this installation blew up twice in the second half of the 20th century and sent massive shockwaves across the bay, breaking windows and rattling walls on the distant shores. False Bay is poor in natural harbours. Almost all protection for shipping and smaller vessels has been created by extending the small naturally protected bays by artificial means (e. g. at Kalkbaai, Simon's Town and Gordon's Bay). During the critical water shortage of the 2018 Cape Town water crisis two reverse osmosis desalination plants were installed at Strandfontein and Monwabisi resort on the north coast of the bay. They were all operating by August 2018,