The Swan River () is a major river in the southwest of Western Australia. The river runs through the centre of Perth, Western Australia's capital and largest city.
By convention the Swan River is deemed to run for from Walyunga National Park down to the river mouth at Fremantle Harbour. Upstream of Walyunga, in the Wheatbelt, the river is known as the Avon. The watercourse as a whole is sometimes known as the Swan-Avon River. The Helena River is the Swan's largest tributary, with other tributaries including various brooks and drains. The Canning River is technically not a tributary of Swan, but rather a separate river which forms an estuary with the Swan at Melville Water, known as the Swan-Canning Estuary.
The Swan River was named by Dutch explorer Willem de Vlamingh in 1697 after the black swans endemic to the region. Following British colonisation the Swan River Colony was established in 1829 with three settlements located on the river: the capital Perth, the port of Fremantle, and the inland town of Guildford. European settlement brought significant changes to the river, including clearing or draining of adjacent wetlands, land reclamation and embankment (including the creation of Heirisson Island), and the removal of the original sandbar at the river mouth. Most areas adjacent to the river are now primarily residential, although the Swan Valley north of Guildford remains a significant agricultural area and wine region.
The Perth central business district is located on Perth Water, a shallower portion of the river, and includes a ferry terminal at Elizabeth Quay, with public Transperth ferry services running to South Perth and private services operating to Fremantle and Rottnest Island. The river and foreshore form part of the Swan Canning Riverpark which is managed by the Western Australian state government's Department of Biodiversity, Conservation and Attractions, replacing the earlier Swan River Trust in 2015.
Course of river
The Swan River estuary flows through the city of Perth. Its lower reaches are relatively wide and deep, with few constrictions, while the upper reaches are usually quite narrow and shallow.
The Swan River drains the Avon and coastal plain catchments, which have a total area of about . It has three major tributaries, the Avon River, Canning River and Helena River. The latter two have dams (Canning Dam and Mundaring Weir) which provide a sizeable part of the potable water requirements for Perth and the surrounding regions. The Avon River contributes the majority of the freshwater flow. The climate of the catchment is Mediterranean, with mild wet winters, hot dry summers, and the associated highly seasonal rainfall and flow regime.
The Avon rises near Yealering, southeast of Perth: it meanders north-northwest to Toodyay about northeast of Perth, then turns southwest in Walyunga National Parkat the confluence of the Wooroloo Brook, it becomes the Swan River.
The Canning River rises from North Bannister, southeast of Perth and joins the Swan at Applecross, opening into Melville Water. The river then narrows into Blackwall Reach, a narrow and deep stretch leading the river through Fremantle Harbour to the Indian Ocean.
The estuary is subject to a microtidal regime, with a maximum tidal amplitude of about , although water levels are also subject to barometric pressure fluctuations.
Naming and terminology The Swan River and the Avon River are the same watercourse. By convention, the name "Avon" is used from the source of the river to its confluence with the Wooroloo Brook in Walyunga National Park, where it assumes the name "Swan". The naming convention has been described as a "historical anomaly". For that reason, the main branch of the river system is sometimes referred to as the Swan–Avon River.
Approximately of the Swan River is estuarine in nature with brackish water, with the effects of ocean tides extending inland as far as the confluence with Ellen Brook. The "true river" portion of the Swan historically culminated in a mudflat delta at what is now Heirisson Island. Technical sources regard the Swan–Avon and Canning as separate rivers flowing into a single body of water, the Swan–Canning Estuary, at Melville Water, rather than treating the Canning as a tributary of the Swan. This distinction was noted as early as 1827 by James Stirling.
Geology Before the Tertiary, when the sea level was much lower than at present, the Swan River curved around to the north of Rottnest Island, and disgorged itself into the Indian Ocean slightly to the north and west of Rottnest. In doing so, it carved a gorge about the size of the Grand Canyon. Now known as Perth Canyon, this feature still exists as a submarine canyon near the edge of the continental shelf.
Geography
The Swan River drains the Swan Coastal Plain, a total catchment area of over in area. The river is located in a Mediterranean climate, with hot dry summers and cool wet winters, although this balance appears to be changing due to climate change. The Swan is located on the edge of the Darling Scarp, flowing downhill across the coastal plain to its mouth at Fremantle.
Sources The Swan begins as the Avon River, rising near Yealering in the Darling Range, approximately from its mouth at Fremantle. The Avon flows north, passing through the towns of Brookton, Beverley, York, Northam and Toodyay. It is joined by tributaries including the Dale River, the Mortlock River and the Brockman River. The Avon becomes the Swan as Wooroloo Brook enters the river near Walyunga National Park.
Tributaries More tributaries including Ellen Brook, Jane Brook, Henley Brook, Wandoo Creek, Bennett Brook, Blackadder Creek, Limestone Creek, Susannah Brook, and the Helena River enter the river between Wooroloo Brook and Guildford; however, most of these have either dried up or become seasonally flowing due to human impacts such as land clearing and development.
Swan coastal plain
Between Perth and Guildford the river goes through several loops. Originally, areas including the Maylands Peninsula, Ascot and Burswood, through Claise Brook and north of the city to Herdsman Lake were swampy wetlands. Most of the wetlands have since been reclaimed for land development. Heirisson Island, upon which The Causeway passes over, was once a collection of small islets known as the Heirisson Islands.
Perth Water and Melville Water Perth Water, between the city and South Perth, is separated from the main estuary by the Narrows, over which the Narrows Bridge was built in 1959. The river then opens up into the large expanse of the river known as Melville Water. The Canning River enters the river at Canning Bridge in Applecross from its source south-east of Armadale. The river is at its widest here, measuring more than from north to south. Point Walter has a protruding spit that extends up to into the river, forcing river traffic to detour around it.
Narrowing and Fremantle
The river narrows between Chidley Point and Blackwall Reach, curving around Point Roe and Preston Point before narrowing into the harbour. Stirling Bridge and the Fremantle Traffic Bridge cross the river north of the rivermouth. The Swan River empties into the Indian Ocean at Fremantle Harbour.
Notable features
Fremantle Harbour Point Brown Rous Head Arthur Head Victoria Quay Point Direction Preston Point Rocky Bay Point Roe Chidley Point Blackwall Reach Butler's Hump Point Walter Mosman Bay Keanes Point Freshwater Bay Point Resolution Melville Water Lucky Bay Point Waylen Alfred Cove Point Dundas Waylen Bay Point Heathcote Quarry Point Mounts Bay Point Lewis Mill Point Point Belches Elizabeth Quay Pelican Point Matilda Bay The Narrows Perth Water Point Fraser Heirisson Island Claise Brook Maylands Peninsula Ron Courtney Island Swan Valley Kuljak Island
Flora and fauna Plant and animal life found in or near the Swan-Canning Estuary include:
Over 130 species of fish including bull sharks (Carcharhinus leucas), rays, cobblers (Cnidoglanis macrocephalus, also known as Swan River catfish), herring (Elops machnata), pilchard (Sardinops neopilchardus), bream (Kyphosus sydneyanus), flatheads, leatherjackets and blowfish (Tetraodontidae) Jellyfish including Phyllorhiza punctata and Aurelia aurita Bottlenose dolphins Crustaceans including prawns and blue manna crabs Amphipod Melita zeylanica kauerti described based on specimen that was collected from under Middle Swan Bridge Molluscs including Mytilidae, Galeommatidae Birds including the eponymous black swan, silver gull, cormorants (locally referred to as "shags"), twenty-eight parrots, rainbow lorikeet, kingfisher, red-tailed black cockatoo, Australian pelican, Australian magpie, heron and ducks
History
The river was named by the Dutch explorer Willem de Vlamingh in 1697, after the famous black swans of the area. Vlamingh sailed with a small party up the river to around Heirisson Island.See also the 1780 usage of the name Black Swan River in – A French expedition under Nicholas Baudin also sailed up the river in 1801.
Governor James Stirling intended that the name Swan River refer only to the watercourse upstream of the Heirisson Islands. All of the rest, including Perth Water, he considered estuarine and which he referred to as Melville Water. The Government notice dated 27 July 1829 stated "the first stone will be laid of a new town to be called 'Perth', near the entrance to the estuary of the Swan River."
Almost immediately after the Town of Perth was established, a systematic effort was underway to reshape the river. This was done for many reasons: to alleviate flooding in winter periods; improve access for boats by having deeper channels and jetties; removal of marshy land which created a mosquito menace; enlargement of dry land for agriculture and building.
Perth streets were often sandy bogs which caused Governor Stirling in 1837 to report to the Secretary of State for Colonies:
Parts of the river required dredging with the material dumped onto the mud flats to raise the adjoining land. An exceptionally wet winter in 1862 saw major flooding throughout the areathe effect of which was exacerbated by the extent of the reclaimed lands. The first bucket dredge in Western Australia was the , used between 1872 and 1911 for dredging channels in the river, as well as reclamation.
Notable features A number of features of the river, particularly around the city, have reshaped its profile since European settlement in 1829:
Claise Brook – named Clause's Brook (after Frederick Clause) on early maps. This was a fresh water creek which emptied the network of natural lakes north of the city. Before an effective sewerage system was built, it became an open sewer which dumped waste directly into the river for many years during the 1800s and early 1900s. The area surrounding has been mainly industrial for most of the period of European settlement and it has a long history of neglect. Since the late 1980s, the East Perth redevelopment has dramatically tidied up the area and works include a landscaped inlet off the river large enough for boats. The area is now largely residential and the brook exists in name only with the lakes having been either removed or managed by artificial drainage systems. Point Fraser – early maps showed this as a major promontory on the northern side of the river west of the Causeway. It disappeared between 1921 and 1935 when land fill was added on both sides, straightening the irregular foreshore and forming the rectangular 'The Esplanade'. The Esplanade – the northern riverbank originally ran close to the base of the escarpment generally a single block width south of St Georges Terrace. Houses built on the southern side of St Georges Terrace included market gardens which ran to the waters edge. Heirisson Islands – a series of mudflats that were slightly more upstream from today's single artificial island which has deep channels on each side.