Deep River (Western Australia)

Deep River is a river located in the Great Southern region of Western Australia.

Deep River
Fernhook Falls on the Deep River
Location
Country	Australia
Physical characteristics
Source
• location	Near Lake Muir
• elevation	183 metres (600 ft)[1]
Mouth
• location	Nornalup Inlet
Length	120 kilometres (75 mi)
Basin size	100 km^2 (39 sq mi)[2]
Discharge
• average	172,000 ML/a (5.5 m^3/s; 192 cu ft/s)[3]

The river is under tidal influence for the last 6 kilometres (4 mi) of its length.

Although generally shallow the Deep River has depths of up to 6.5 metres (21 ft) in places. The Deep River is one of the few perennial rivers in Western Australia although 80% of its discharge occurs in winter and spring.

The rivers water quality is very good, fresh and low in nutrients. The majority of the catchment of the Deep River is not cleared. The silt and clay content can be high during the winter period. The Deep River begins just west of Lake Muir about 50 km from the coast on the edge of the Yilgarn Plateau. Lake Muir may, in flood, overflow into the Deep River catchment. It flows through a valley between granite hills then wanders across the coastal plain finally entering the Nornalup Inlet on the western side.[4]

The two tributaries of the Deep River are the Weld River and Croea Brook.

Some features of the river include wide unobstructed pools interspersed with rapids such as Rowell's Pool and two waterfalls, Fernhook Falls and Gladstone Falls.[5]

The Deep River flows through forested areas of National Park including the Walpole-Nornalup National Park before discharging into the Nornalup Inlet.

The first recorded name of the river was given in 1841 by the Colonial Secretary, Peter Broun. It had been known as the Frankland River by sealers that operated in the area. The explorer William Nairne Clark named it the West River on his charts but Broun later decided on the current name.[6]

References

1. "Bonzle Digital Atlas - Map of Deep River, WA". 2008. Retrieved 23 November 2008.
2. "Walpole Nornalup Indicative Management Plan". 2006. Retrieved 11 June 2007.
3. "South Coast Rivercare - Deep River". 2007. Archived from the original on 29 July 2007. Retrieved 17 June 2007.
4. Smith (April 2003). Hydrogeology of the Muir–Unicup catchments (pdf). East Perth, WA: Water and Rivers Commission. p. 5. ISBN 1-920849-12-2. Retrieved 21 January 2017.
5. "Walpole Wilderness Proposal" (PDF). 1998. Retrieved 9 August 2009.
6. Western Australian Land Information Authority. "History of river names – D". Retrieved 3 September 2011.