|Etymology||In honour of J. C. Shannon|
|State||New South Wales|
|Region||NSW North Coast (IBRA), Northern Rivers|
|Source confluence||Theresa Creek and Deep Creek|
|⁃ location||near Mummulgum|
|⁃ elevation||96 m (315 ft)|
|Mouth||confluence with the Richmond River|
|5 m (16 ft)|
|Length||58 km (36 mi)|
|River system||Richmond River catchment|
|⁃ left||Rileys Creek|
|⁃ right||Mongogarie Creek|
Location and features
Formed by the confluence of the Theresa Creek and Deep Creek, Shannon Brook rises on the Richmond Range about 8 kilometres (5.0 mi) southwest of Mummulgum. The river flows generally northeast, east southeast and east, joined by two minor tributaries before reaching its confluence with the Richmond River near Tatham, about 13 kilometres (8.1 mi) southeast of Casino. The river descends 91 metres (299 ft) over its 58 kilometres (36 mi) course.
The river is believed to be named in honour of J. C. Shannon who came from the Clarence Valley and took up Stratheden for Dr. John Dobie in 1842. He camped by the creek, hence the name Shannon Brook. J. C. Shannon was known locally as Doc Shannon.
- "Shannon Brook". Geographical Names Register (GNR) of NSW. Geographical Names Board of New South Wales. Retrieved 2 October 2013.
- "Map of Shannon Brook, NSW". Bonzle Digital Atlas of Australia. Retrieved 2 October 2013.
- Richmond Tweed Regional Library (1983). Place Names of the Tweed, Brunswick and Upper Richmond Regions. ISBN 0-9494-5901-1.