Colour patch area at mouth of Blackwood river and start of eastern section of estuary
|• location||Junction of Arthur River and Balgarup River|
|• elevation||219 metres (719 ft)|
|Hardy Inlet, Augusta|
|Length||300 kilometres (186 mi)|
|Basin size||28,100 km2 (10,849 sq mi)|
|• average||29.8 m3/s (1,050 cu ft/s)|
The Blackwood River is a major river and catchment in the South West of Western Australia.
The river begins at the junction of Arthur River and Balgarup River near Quelarup and travels in a south westerly direction through the town of Bridgetown then through Nannup until it discharges into the Southern Ocean at Hardy Inlet near the town of Augusta.
Hardy Inlet has a number of islands – namely Molloy Island and Thomas Island. The mouth of the river has attracted interest in its various points of opening and closing over the last 100 years, Duke Head at the west side being a benchmark location for the shifting mouth.
The river has 41 tributaries including Dinninup Brook, Balingup Brook, St John Brook, Boyup Brook, Tweed River, Ti Tree Gully, Christmas Creek and Tanjannerup Creek.
The river has a total catchment area of 28,100 square kilometres (10,849 sq mi) stretching from Kukerin in the east to Hardy Inlet in the west, and from Darkan in the north to Augusta in the south.
Several major towns are found within the catchment including Katanning, Narrogin, Bridgetown and Nannup.
The upper or larger catchment area of the river is in agricultural areas, while the middle catchment area passes through forest areas, and the lower portion of the river passes into mixed forest, agricultural and residential lands. The middle catchment passes through what is known as the Blackwood Plateau between the Whicher Scarp and the Scott Coastal Plain.
The river emerges into Flinders Bay at Augusta.
The majority of the basin, 78%, is devoted to agriculture, including cereal production and grazing. There are still many significant water resources including over 1,000 wetlands, as well as the river itself.
The basin is habitat for an estimated 8,000 species of flora including three threatened ecological communities. A total of 42 rare and priority vertebrate fauna species and 143 rare and priority flora species are found within the basin catchment area.
Aboriginal Australians have lived along the Blackwood River for thousands of years. The Bibulman Noongar people called the river Gurbillup buerle, "burle" meaning "river", while the portion of the river at Bridgetown was called Gigellup buerle.
In 1827, Captain James Stirling arrived at the river and named it after Vice-Admiral Sir Henry Blackwood, under whom he served as a midshipman on HMS Warspite in 1808–1809 during the Napoleonic Wars, in the North Sea and the Mediterranean.
Historically it was of considerable importance in the early days of the Swan River Colony, and more recently of importance in the ecology of the Augusta-Margaret River region due to conflicts in land use policy. The upper catchment contains Toolibin Lake, a nature reserve and Ramsar site.
The river is prone to occasional flooding. In 1945 it rose to the highest level recorded to that date, running 1.1 metres (3.6 ft) over the Russell Street bridge in Nannup. The river flooded again in 1946 and 1947 closing roads but not causing any significant damage to towns along the river. In 1949 Nannup received 174 millimetres (6.85 in) of rain in a period of seven hours, causing flooding. A bridge over the Blackwood connecting the town to Busselton was swept away.
In 1982 after the remnants of a tropical cyclone passed through the southwest, the town and surrounding areas were inundated by heavy rains. The Blackwood rose 11.6 metres (38 ft), submerging over 50 houses in Nannup.
The Murchison River is the second longest river in Western Australia. It flows for about 820 km (510 mi) from the southern edge of the Robinson Ranges to the Indian Ocean at Kalbarri. The Murchison-Yalgar-Hope river system is the longest river system in Western Australia. It has a mean annual flow of 208 gigalitres, although in 2006, the peak year on record since 1967, flow was 1,806 gigalitres.
The South West region is one of the nine regions of Western Australia. It is so named because it is located in the south-west corner of Western Australia. The South West region has an area of 23,970 km², and a population of about 170,000 people, which is predicted to rise to 217,000 people by 2023. Bunbury is the capital of the region.
Bridgetown is a town in the South West region of Western Australia, approximately 270 kilometres (168 mi) south of Perth on the Blackwood River at the intersection of South Western Highway with Brockman Highway to Nannup and Augusta.
South Western Highway is a highway in the South West region of Western Australia connecting Perth's southeast with Walpole. It is a part of the Highway 1 network for most of its length. It is about 406 kilometres (252 mi) long.
Nannup is a town in the South West region of Western Australia, approximately 280 kilometres (174 mi) south of Perth on the Blackwood River at the crossroads of Vasse Highway and Brockman Highway; the highways link Nannup to most of the lower South West's regional centres. At the 2011 census, Nannup had a population of 587.
Moore River is a river in the Wheatbelt region of Western Australia.
The Greenough River is a river in the Mid West region of Western Australia.
Donnelly River Village is a former timber mill town and present-day holiday village in the Shire of Nannup, in the South West region of Western Australia. The Village is located at a point between Nannup, Bridgetown and Manjimup on the Donnelly River, a small, seasonal river at this point, which flows into the Southern Ocean at 34°29'02.4"S 115°40'27.8"E. The name also applies to a winery downstream on the Vasse Highway and the township's cottages are sometimes confused with cottages built on the lower reaches of the Donnelly River at 34.482273S 115.683438E.
The Shire of Nannup is a local government area in the South West region of Western Australia, approximately 280 kilometres (174 mi) south of the state capital, Perth and 60 kilometres (37 mi) southeast of the coastal resort town of Busselton. Its seat of government is the town of Nannup, where about half of the Shire's population reside.
The Peel-Harvey Estuarine System is a natural estuarine system that lies roughly parallel to the coast of Western Australia and south of the town of Mandurah. The strip of land between the Indian Ocean and the estuarine system carries the Old Coast Road and to the east is the Forrest Highway which is the main thoroughfare between Perth and the coastal towns of the south west corner of the state including Bunbury and Busselton.
The Murray River is a river in the southwest of Western Australia. It played a significant part in the expansion of settlement in the area south of Perth after the arrival of British settlers at the Swan River Colony in 1829.
Nornalup Inlet is an estuarine body of water on the south coast of the South West of Australia, approximately 450 km (280 mi) from Perth.
Blackwood Valley is a wine region in the south-west of Western Australia, approximately 260 km south-south-east of Perth.
Blackwood-Stirling was an electoral district of the Legislative Assembly in the Australian state of Western Australia. It took parts of the South West and Great Southern regions of Western Australia.
The Lower South West Football League is a country Australian rules football league incorporating teams from towns located within the South West and Great Southern regions of Western Australia.
The Preston River is a river in the South West region of Western Australia.
Irwin Inlet is an inlet in the located on the Great Southern region of Western Australia.
Sussex Land District is a land district of Western Australia, located within the South-West Land Division on the state's west coast. It covers the south-western corner of the state and includes the townsites of Busselton, Margaret River and Augusta as well as Cape Naturaliste and Cape Leeuwin.
Hardy Inlet is an inlet that is located in the South West region of Western Australia.
Scott River is a river in the south west of Western Australia, being a tributary to the Blackwood River where it joins just east of Molloy Island. It is partly within the Scott National Park, which is named after the river.