Kolan Rivers

This brochure describes the flood risk and previous flooding in the Kolan River catchment, last updated in August 2025.

Flood Risk

The Kolan River Catchment is located in southeast Queensland and covers an area of approximately 3,000 square kilometres. The river rises in the rugged Dawes Range, 100 kilometres northwest of Bundaberg. It meanders for a distance of 70 kilometres, generally in a southeasterly direction, before entering Lake Monduran and passing through the Fred Haigh Dam.

Below the Dam and the Bucca Range, the Kolan River enters a wide coastal plain, generally under large areas of sugar cane cultivation. Gin Gin Creek, its major tributary, rises in the Burnett Range 35 kilometres west of Gin Gin and flows in an easterly direction joining the Kolan River 10 kilometres above Bucca Weir.

Floods normally develop in the headwaters of the Kolan River and Gin Gin Creek and its major tributaries. However, Fred Haigh Dam has a significant effect on reducing major flooding in the lower reaches. Flooding from local area heavy rainfall may still occur in areas downstream of Bucca Weir.

Fred Haigh Dam was completed in 1974, with only minor to moderate flooding being recorded between this time and December 2010. In January 2013 the dam spilled by 6.85 metres causing widespread major flooding downstream.

Previous Flooding

Previous flood information for the Kolan River is well documented. Monduran has peak heights dating back to 1887, with Molangool dating back to 1967. Record major flooding was recorded in the Kolan River at Bucca Weir in January 2013 (Tropical Cyclone Oswald). Major flooding was also recorded along the Kolan River in March/April and October 2017 (Tropical Cyclone Debbie).

The main impacts of flooding on the Kolan River and Gin Gin Creek are the disruption of transport routes. In major floods, this can include the Bruce Highway and North Coast Rail Line, as well as isolation of property. In major floods, inundation of residential properties can occur. Flash flooding can occur at Agnes Water, Lowmead, Miriam Vale, Rosedale, Colonial Cove (Baffle Creek), Leixlip Creek (Calliope), upstream of Awoonga Dam, Gladstone, and Gin Gin.

Floods normally develop along the Calliope River and its major tributaries, as well as along the Baffle and Euleilah creeks and their major tributaries.

The table below summarizes the flood history of the Kolan River Catchment – it contains the flood gauge heights of some of the more recent significant flood peaks.

Flood Event	Monduran	Molangool	Bucca
Dec 1973	-	9.53	-
Mar 1992	-	10.3	20.95
Dec 2010	9.1	-	18.73
Mar 2012	5.0	-	19.64
Jan 2013	13.3	-	23.84
Mar 2017	-	-	19.61
Oct 2017	-	-	20.06

 

All heights are in metres on flood gauges.