Moonie River

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

Flood Risk

The Moonie River basin is located in southwest Queensland and drains an area of approximately 15,500 square kilometres. The rivers rises near the Braemar State Forest (between Dalby and Tara) and flows generally to the south-west and is joined by thirteen minor tributaries, before reaching its confluence with the Barwon River before Mogil Mogil farm (north of the village of Collarenebri in New South Wales).

The largest tributary is Teelba Creek and flows into the Moonie River between Flinton and Mt Driven. This tributary, along with local streams running into the Moonie River upstream of Flinton, can contribute to major flooding following heavy rainfall. River levels rise fast in the upper reaches of the Moonie, in the lower reaches, flooding is characterised by slow and long river level rises, followed by flood peaks that can remain above flood levels for a week or more.

In significant floods breakout flows from the Balonne River system can impact the lower Moonie River system.

Major flooding on the Moonie can cause many thousands of hectares of low-lying areas to be inundated, properties to be isolated and highways to be cut. The Barwon Highway at Nindigully and the bridge at Thallon are subject to flooding during major flood events.

Previous Flooding

Flood records for Nindigully and Thallon date back to 1970 and 1950 respectively. The highest flood on record occurred in March 2010 when the river rose to a height of 4.65 metres at Nindigully and to 5.50 metres at Thallon. Since 2010, significant flood events with peak heights above major flood level have occurred in 2011, 2012, 2013, 2022 and 2024 at either one or both locations.

More recently a major flood peak of 5.15 metres (major flood level 5.0 m) was observed at Thallon Bridge in March 2022, and 5.03 metres in February 2024. While upstream at Nindigully, peak heights of 3.87 metres (moderate flood level 3.0 m) and 3.75 metres were recorded during these flood events.

The table below summarises the flood history of the Moonie River basin - it contains the flood gauge heights of the more significant recent floods.

Flood Event	Southwood	Flinton	Nindigully	Thallon	Fenton
Apr 1988	5.60	5.02	3.88	5.33	5.11
Jan/Feb 1996	6.35	4.60	3.39	5.26	4.73
Aug/Sep 1998	6.30	5.06	3.93	5.36	5.03
Mar 2010	5.90	5.00	4.65	5.50	5.48
Jan 2011	6.90	5.05	3.88	5.36	4.94
Jan/Feb 2012	6.10	4.00	4.10	5.40	5.30
Jan/Feb 2013	6.65	4.98	3.78	5.14	4.83
Feb/Mar 2022	5.45	4.95	3.87	5.15	4.79
Jan/Feb 2024	6.45	4.87	3.75	5.03	4.86

 

All heights are in metres on flood gauges.