Fitzroy: Climate and water

  • Total annual rainfall for the 2021-22 year was above average for the first time since 2016-17.
  • Record rainfall during November resulted in the highest recorded streamflows for some sites during November and December, but overall streamflow was below average.
  • Soil moisture in the root zone (0–1m depth) was above average across most of the region.

Schematic representation of the Fitzroy region. In 2021–22, rainfall was 762 mm, higher than average for the first time since 2016-17. Streamflow in Fitzroy River in 2021–22 was 3477 GL compared to the average value of 4,908 GL. Soil moisture was above average.

For further information on the region's climate and water conditions during the 2021-22 year scroll down this page or click on the links below:

 

About the region

  • The Fitzroy region has a sub-tropical, semi-arid climate with a high inter-annual variability in rainfall and streamflow.
  • Most of the rainfall occurs during the wet season (November–April). As a consequence, flow in the rivers is strongly seasonal and many of the region's rivers cease to flow during the dry season (May–October).

 

Climate conditions

Rainfall

Figure C1 Annual and monthly rainfall deciles for the Fitzroy region during the 2021-22 year

  • Total area-averaged rainfall for the 2021-22 year was 762 mm, 13% above the mean value of 675 mm. This was the first time the region had experienced above-average rainfall since 2016-17.
  • While no significant rainfall was recorded from July to October 2021, the development of the La Niña during late spring created favourable conditions for increased rainfall over eastern Australia and the region experienced it's wettest November on record.
  • In contrast, January to March (when stramflows would typically be peaking) was unusally dry. 
  • Nearly three times the long-term average monthly rainfall fell across the region during May 2022.
  • More information on Australia's climate and water over the 2021-22 year can be found at: Financial year climate and water statement 2021-22.

 

Figure C2 Total monthly rainfall for the Fitzroy region during the 2021-22 year compared with the average and percentiles for the region

  • Rainfall during November 2021 and May 2022 was well above the 90th percentile, with region recording its wettest November on record.
  • January was the only month during the 2021-22 year to record rainfall below the 10th percentile.

 

Actual evapotranspiration

Figure C3 Annual and monthly actual evapotranspiration deciles for the Fitzroy region during the 2021-22 year

  • Total area-averaged actual evapotranspiration was above average across most of the region for the 2021-22 year.
  • Increased water availability from heavy rainfall during November saw well above average evapotranspiration from late November into December.
  • Evapotranspiration remained average to below average from January through to April 2022 as relatively low rainfall across this period reduced water availability.
  • Further significant rainfalls in May created conditions for above average evapotranspiration in May through June 2022.

 

Soil moisture

Figure C4 Annual and monthly soil moisture deciles for the Fitzroy region during the 2021-22 year

  • Soil moisture in the root zone (0–1m depth) was mostly average to above average for the 2021-22 year.
  • With close to average soil moisture in lead up, heavy rainfall during November 2021 increased soil moisture to well above average across the region in November and December.
  • As a result of below-average rainfall over summer and early autumn, the root zone was relatively dry from January through to April, particularly in the north.
  • Further widespread rainfall in May was enough to return to soil moisture to above average across the region through May and June.
  • More information on soil moisture distribution across the Fitzroy region is available in the Australian Water Outlook.

 

Streamflow responses

Map of key gauging stations. Nogoa River at Craigmore, station number 130209A, approximately 40 km upstream of Fairbairn Dam. Comet River at The Lake, station number 130506A. Dawson River at Taroom, station number 130209A, in the south near Taroom. Isaac River at Yatton, station number 130401A, in the north. Mackenzie River at Coolmaringa, station number 130105A, approximately 100 km west of Rockhampton. Fitzroy River at The Gap, station number 130005A, approximately 50 km upstream of Rockhampton.
Figure C5 Key flow gauging stations along the main rivers within the Fitzroy region

  • The six main rivers in the region are the Fitzroy, Dawson, Nogoa, Mackenzie, Isaac, and Comet rivers, which correspond to the six sub-basins used for environmental water management (see the Water management section in 'Region description' for more information).

 

Figure C6 Total monthly flow for major rivers in the Fitzroy region during the 2021-22 year compared with the average and percentiles

  • Despite above average annual rainfall, the total annual flows in the region's major rivers (except the Dawson River) were below average for 2021-22 reflecting the low wet season rainfall.
  • The annual streamflow in the Fitzroy River at The Gap (Station 130005A) was around 30% below average at 3,477 GL compared to the annual average of 5,000 GL. 
  • Following heavy rainfall, most streamflows peaked at or above the 90th percentile during November and December and then again in May.
  • During the January to April period when streamflow would typically be highest, much lower than average flows were recorded across the region due to poorer than usual rainfall.