Question 3. What is the persistence time of waterholes in the Lower Balonne and Barwon–Darling? Findings: The average persistence time for modelled waterholes in the Culgoa River valley was 377 days (maximum 587 days at Weilmoringle GS). The average persistence time for modelled waterholes the Narran River valley was 355 days (maximum 637 days at Angledool). In the Barwon–Darling, the persistence time, based on uncalibrated models, ranged from 1083 days Gate) to 1953 days (Akuna/Weir 20A). (Hell’s Modelled waterhole persistence times were validated by remote sensing analysis (Chapter 2). What does this mean? Modelled waterholes in the Lower Balonne do not persist as long as previously thought; the majority of waterholes did not persist longer than one year and none persisted beyond two years. Question 4. Does groundwater influence the persistence time of waterholes in the Lower Balonne and Barwon–Darling? Findings: Groundwater contribution to waterholes along the Narran and Culgoa rivers is minor. Groundwater interaction maybe be greater in the Barwon–Darling, but does not contribute significantly to waterhole persistence. What does this mean? Groundwater interactions did not need to be explicitly included in the calibration of persistence models for the Lower Balonne (Chapter 3). Question 5. Does sedimentation affect waterhole persistence in the Lower Balonne and Findings: The average depth of accumulated soft sediment in the Lower Balonne was 25 centimetres (approximately 11 per cent of average maximum waterhole depth in the Narran and Culgoa Rivers). The average depth of accumulated soft sediment for the Barwon–Darling was 28 centimetres (approximately 4 per cent of average maximum waterhole depth in the Barwon–Darling). Waterholes in the Lower Balonne were shallower than the Barwon–Darling. What does this mean? Additional findings from sedimentation rate analysis will be provided in a supplementary report. Question 6. Can the persistence time of waterholes across the northern Basin be predicted using a generic model? Findings:
Question 3. What is the persistence time of waterholes in the Lower Balonne and Barwon–Darling? Findings: The average persistence time for modelled waterholes in the Culgoa River valley was 377 days (maximum 587 days at Weilmoringle GS). The average persistence time for modelled waterholes the Narran River valley was 355 days (maximum 637 days at Angledool). In the Barwon–Darling, the persistence time, based on uncalibrated models, ranged from 1083 days (Hell’s Gate) to 1953 days (Akuna/Weir 20A). Modelled waterhole persistence times were validated by remote sensing analysis (Chapter 2). What does this mean? Modelled waterholes in the Lower Balonne do not persist as long as previously thought; the majority of waterholes did not persist longer than one year and none persisted beyond two years. Question 4. Does groundwater influence the persistence time of waterholes in the Lower Balonne and Barwon–Darling? Findings: Groundwater contribution to waterholes along the Narran and Culgoa rivers is minor. Groundwater interaction maybe be greater in the Barwon–Darling, but does not contribute significantly to waterhole persistence. What does this mean? Groundwater interactions did not need to be explicitly included in the calibration of persistence models for the Lower Balonne (Chapter 3). Question 5. Does sedimentation affect waterhole persistence in the Lower Balonne and Findings: The average depth of accumulated soft sediment in the Lower Balonne was 25 centimetres (approximately 11 per cent of average maximum waterhole depth in the Narran and Culgoa Rivers). The average depth of accumulated soft sediment for the Barwon–Darling was 28 centimetres (approximately 4 per cent of average maximum waterhole depth in the Barwon–Darling). Waterholes in the Lower Balonne were shallower than the Barwon–Darling. What does this mean? Additional findings from sedimentation rate analysis will be provided in a supplementary report. Question 6. Can the persistence time of waterholes across the northern Basin be predicted using a generic model? Findings:
FINAL%20Report_Waterholes%20Project%20northern%20Basin.docx