|State||New South Wales|
|Region||South Eastern Highlands (IBRA), Monaro|
|Local government area||Snowy Monaro Regional Council|
|Source confluence||Badgerys Creek and Horseys Swamp Creek|
|⁃ location||near Cathcart|
|⁃ elevation||803 m (2,635 ft)|
|Mouth||confluence with the Bombala River|
|698 m (2,290 ft)|
|Length||26 km (16 mi)|
|River system||Snowy River catchment|
|⁃ right||Dragon Swamp Creek|
Course and features
The Coolumbooka River is formed by the confluence of the Badgerys Creek and the Horseys Swamp Creek in a swampy area, located approximately 10 kilometres (6.2 mi) east northeast of the village of Cathcart. The river flows generally west southwest, joined by one minor tributary before reaching its confluence with the Bombala River near the town of Bombala. The river descends 105 metres (344 ft) over its 26 kilometres (16 mi) course, flowing through the northern boundary of the Coolumbooka Nature Reserve.
The river is impounded by Coolumbooka Weir that provides water supply to the town of Bombala.
- "Coolumbooka River". Geographical Names Register (GNR) of NSW. Geographical Names Board of New South Wales. Retrieved 2 June 2013.
- "Map of Coolumbooka River, NSW". Bonzle Digital Atlas of Australia. Retrieved 2 June 2013.
- "Coolumbooka Weir". Geographical Names Register (GNR) of NSW. Geographical Names Board of New South Wales. Retrieved 2 June 2013.