Reflections off still waters

Chasing the Flood

Thick muddy river bank

The upper Condamine runs along the border ranges and the water rises and falls in a fairly consistent manner along this stretch. So this would be the most important section to stay with the high flows. Previous floods suggest about a week of flowing waters, but as it is 426 km between Warwick and Chinchilla, it would be a stretch to paddle this section in 7 days (60 km / day)!

Below Chinchilla you should slowly catch up with the flow as you make your way down to St George (475 km away) with the flood waters travelling about 35 km / day, and easily catch it by Weilmoringle (350 km from St George) or Bourke (590 km from St George) as the waters flow slows to around ~25 km / day in the Culgoa.

While the Condamine River catchment is large, most of the flow into the Darling will be from the Barwon River with catchments along the western side of the Great Dividing Range from Sydney to QLD. From Bourke, you will likely be ahead of the flood waters from the Condamine, but if there is any flow, you shouldn't have any issues in the downstream section. With a widespread flood event, you will likely be meeting flood waters from the Barwon.

Bourke to Menindee is just under 1,000 km and flow is likely to take about 6 to 8 weeks (20 km / day), two weeks to Wilcannia, two more weeks to Menindee at 30 km / day.

From the flows seen this year, there is a remarkable predictability of the flow down the river in a flood event. From Bourke (22 Feb), the water took 4 days to reach Louth, 3 days 13 hrs more for Tilpa, 6 days 9 hrs more to Wilcannia and started filling Lake Wetherell 4 days 20 hrs later. The second rain event happened when there was water still flowing in the system and the flow peak speed increased slightly as shown in the table below. The other flow event that was looked at was from 2003 and was slower (smaller rain event).

Town Distance From Bourke Days taken (Speed)
Dry Flow 2003 Dry Flow 2020 Wet Flow 2020
Louth 205 km 5 days 8 hrs (1.6 km/h)
38.5 km per day		 4 days (2.1 km/h)
51 km per day		 2 days 15 hrs (3.3 km/h)
78 km per day
Tilpa 373 km
168 km from Louth		 4 days 7 hrs (1.6 km/h)
39 km per day		 3 days 13 hrs (2 km/h)
47.5 km per day		 3 days 13 hrs (2 km/h)
47.5 km per day
Wilcannia 644 km
271 km from Tilpa		 8 days 12 hrs (1.3 km/h)
32 km per day		 6 days 9 hrs (1.8 km/h)
42.5 km per day		 4 days 4 hrs (2.7 km/h)
65 km per day
Lake Wetherell 922 km
278 km from Wilcannia		 5 days 8 hrs (1.6 km/h)
52 km per day		 4 days 20 hrs (2.4 km/h)
57.5 km per day		 undetermined

So if you want to stay with the flow from a heavy rain event, you are looking at approx. 40 to 50 km days when dry and up to 65 km days when wet. However since the upper catchment area spans over 1,000 km between Sydney and Brisbane, the flow from any rain event is likely to last for weeks giving you plenty of time to enjoy the trip down without pushing long days. Also you have at least two weeks for the flow to drop under 10 Cumecs if the peak was above 5,000 ML/day. This gives 30 km days would be enough to enjoy high flows and even longer if you are happy to paddle flat water down.

Below Menindee, there should be a fairly slow continuous flow if the lakes are filled. This is under complete control of the MDBA. Refer to their weekly reports about the water releases, or lack of, within the system.

Chart showing river flow at different times down the darling river
Chart showing river flow at different times down the darling river

Raw Data from the Feb 2020 Flood

There was an initial rain event that caused a major flood event around Dalby, and a second event a week later that caused higher flows around the source.

This second event at the Head took about 12 hrs from the peak seen at Killarney (Brosnans Barn) to reach Warwick. Due to continued flooding around Dalby, it is difficult to see when this water started to affect downstream stations, but approx. 1 to 2 days to affect Cecil Weir. From here this second event appeared to have no to little effect on the primary flooding event.

Early estimates (29th Feb) based on the flood peak dates are for a flow of 1.8 km / hr, so you would need to be traveling 43.5 km per day to stay with the peak and this would relate to a 2 month journey from Dalby to Wentworth!

  • Prior: 0.36m
  • Peak: 1.85m (below minor 3m)
  • +12 hr: 1.35m
  • +24 hr: 1.09m
  • +36 hr: 0.97m
  • +48 hr: 0.87m
  • +60 hr: 0.75m
  • Prior: -0.06m
  • Peak: 2.09m (below minor 5m)
  • +12 hr: 1.78m
  • +24 hr: 1.57m
  • +36 hr: 1.41m
  • +48 hr: 1.26m
  • +60 hr: 1.15m

From Dalby down, there was a bigger rain event in their catchment.

  • Prior: 1.55m
  • Rising: 14:00 09/02/2020
  • Minor: 16:00 09/02/2020 (2.5m)
  • Moderate: 20:00 09/02/2020 (3.5m)
  • Peak: 4.75m (moderate flood)
  • +1 day: 4.49m
  • +2 day: 3.93m
  • +3 day: 3.22m
  • +4 day: 3.02m
  • +5 day: 2.99m
  • +6 day: 2.60m
  • +7 day: 2.20m

Chinchilla, peaked 13:00 14/02/2020. 1 day 18 hrs after Dalby (143 km away). Peak speed from Dalby was 3.4 km / hr.

  • Prior: 1.03m
  • Rising: 21:00 07/02/2020
  • Minor: 00:00 12/02/2020 (6m)
  • Moderate: 23:00 12/02/2020 (8m)
  • Major: 22:00 13/02/2020 (10m)
  • Peak: 10.65m
  • +1 day: 10.14m
  • +2 day: 9.05m
  • +3 day: 7.59m
  • +4 day: 5.11m
  • +5 day: 3.31m
  • +6 day: 2.34m
  • +7 day: 1.49m

Condamine, peaked 16/02/2020 9:00 PM. 2 days 8 hrs after Chinchilla (85 km away). Peak speed from Chinchilla was 1.5 km / hr, peak speed from Dalby was 2.3 km / hr.

Surat. Peaked at 26/02/2020 19:00. 6 days 6 hrs after Condamine (211 km away). Peak speed from Chinchilla was 0.9 km / hr, peak speed from Dalby was 1.3 km / hr

  • Prior: 2.86m (0 cumecs)
  • Rising: 08:00 07/02/2020
  • Minor: 16:00 10/02/2020 (4.8m)
  • Moderate: 15:00 15/02/2020 (6.8m)
  • Major: 18:00 20/02/2020 (8.8m)
  • Peak: 10.2m (800 cumecs)
  • +1 day: 9.7m
  • +2 day: 9.0m
  • +3 day: 8.8m
  • +4 day: 9.8m
  • +5 day: 10.2m (effectively a second peak from Balonne River flows)
  • +6 day: 9.6m
  • +7 day: 9.1m
  • +8 day: 8.8 m
  • +9 day: 8.3 m (375 cumecs)
  • +10 day: 7.6 m
  • +11 day: 6.3 m
  • +12 day: 4.3 m
  • +13 day: 3.5 m (26.3 cumecs)
  • +14 day: 3.4 m
  • +15 day: 3.3 m
  • +16 day: 3.3 m
  • +17 day: 3.2 m

St. George. Peaked at 27/02/2020 08:30. Peak was only about 16 hrs after Surat (179 km away), but nearly a week from when Surat first recorded major flooding. Peak speed from Dalby was 1.7 km / hr

  • Prior: 0.76m (0 cumecs)
  • Rising: 13:00 11/02/2020
  • Minor: 13:00 22/02/2020 (6m)
  • Moderate: 03:00 23/02/2020 (8m)
  • Major: 25/02/2020 11:30 (10m)
  • Peak: 11.8m (2,300 cumecs)
  • +1 day: 11.2m
  • +2 day: 10.4m
  • +3 day: 9.7m
  • +4 day: 8.9m
  • +5 day: 7.8m (700 cumecs)
  • +6 day: 6.5m
  • +7 day: 5.4m
  • +8 day: 3.3m (124 cumecs)
  • +9 day: 2.1m (24 cumecs)

Whyenbah (near the head of the Culgoa River). From Dalby, peak reach the Culgoa River with a rate of 1.8 km / hr from Dalby.

  • Prior: 0.37m (0 cumecs)
  • Rising: 05:00 16/02/2020
  • Minor: 09:00 17/02/2020 (3.5m)
  • Moderate: 19:00 22/02/2020 (5.0m)
  • Major: 03:00 24/02/2020 (5.8m)
  • Peak: 6.4m 20:00 28/02/2020 (360 cumecs)
  • +1 day: 6.4m
  • +2 day: 6.4m
  • +3 day: 6.4m
  • +4 day: 6.3m
  • +5 day: 6.3m (290 cumecs)
  • +6 day: 6.3m (130 cumecs)
  • +7 day: 5.9m (207 cumecs)
  • +8 day: 5.2m (145 cumecs)
  • +9 day: 3.9m (84 cumecs)
  • +10 day: 3.0m (24 cumecs)
  • +15 day: 3.0m (24 cumecs) - I kayaked thought on this day

Peaked at 17/03/2020 11:00 (5.49m), 1cm below moderate flood. Peak travelled at 1.2 km / hr from Dalby.

  • Prior: 0.92m
  • Rising: 26/02/2020 00:15
  • Minor: 14/03/2020 22:00 (5.2m)
  • Peak: 17/03/2020 11:00 (5.49m)
  • +1 day: 5.47m 8,100 ML/d
  • +2 day: 5.41m 7,200 ML/d
  • +3 day: 5.27m 6,300 ML/d - I kayaked through on this day
  • +4 day: 4.88m 4,590 ML/d
  • +5 day: 4.39m 3,650 ML/d
  • +6 day: 4.12m 3,250 ML/d
  • +7 day: 3.80m 2,800 ML/d
  • +8 day: 3.31m 2,100 ML/d
  • +9 day: 2.86m 1,480 ML/d
  • +10 day: 2.60m 1,130 ML/d
  • +11 day: 2.41m 850 ML/d
  • +12 day: 2.26m 630 ML/d
  • +13 day: 2.15m 460 ML/d
  • +14 day: 2.07m 360 ML/d
  • +15 day: 2.02m 290 ML/d

It appears the second peak at 12/03/2020 midnight (6.2m) was from the Culgoa. Peak travelled at 1.0 km / hr from Dalby. Flow from the larger Barwon River makes this estimate fairly iffy.

  • Prior: 2.8m (20/02/2020 from Barwon) or 5.5m (01/03/2020 from Barwon and Culgoa)
  • Rising: 19:00 01/03/2020
  • First Peak: 6.3m (184 cumecs) 11:00 06/03/2020 Barwon
  • Second Peak: 6.2m 00:00 12/03/2020 Barwon and Culgoa
  • +1 day: 6.10m 14,600 ML/d
  • +2 day: 5.93m 13,600 ML/d
  • +3 day: 5.73m 12,300 ML/d
  • +4 day: 5.57m 11,200 ML/d
  • +5 day: 5.49m 10,600 ML/d
  • +6 day: 5.42m 10,200 ML/d
  • +7 day: 5.38m 9,900 ML/d
  • +8 day: 5.32m 9,500 ML/d
  • +9 day: 5.29m 9,300 ML/d

Level of 0.66m increased to about 5m / 120 Cumecs from 24/02/2020 20:00 over a number of days. Peak appears to be a weir release upstream and not from the actual flow at Bourke. Assuming Weir 19a for lack of any other info (55 km downstream Bourke).

  • Prior: 0.66m
  • Rising: 19:00 24/02/2020
  • Peak: 5.9m
  • +1 day: 5.86m 14,000 ML/d
  • +2 day: 5.77m 13,800 ML/d
  • +3 day: 5.69m 13,500 ML/d
  • +4 day: 5.64m 13,400 ML/d
  • +5 day: 5.66m 13,400 ML/d
  • +6 day: 5.70m 13,600 ML/d
  • +7 day: 5.69m 13,500 ML/d
  • +8 day: 5.59m 13,200 ML/d
  • +9 day: 5.43m 12,700 ML/d
  • +10 day: 5.24m 12,000 ML/d
  • +11 day: 5.06m 11,400 ML/d
  • +12 day: 4.91m 10,800 ML/d
  • +13 day: 4.79m 10,400 ML/d
  • +14 day: 4.69m 10,000 ML/d
  • +15 day: 4.62m 9,800 ML/d

Level of 0m increased to about 5m from 28/02/2020 02:00 over a number of days.

  • Prior: 0m
  • Rising: 1:00 28/02/2020
  • Peak: 6.10m 16:00 10/03/2020
  • +1 day: 6.03m 13,300 ML/d
  • +2 day: 6.00m 13,200 ML/d
  • +3 day: 5.97m 13,100 ML/d
  • +4 day: 5.98m 13,100 ML/d
  • +5 day: 5.98m 13,100 ML/d
  • +6 day: 5.97m 13,100 ML/d
  • +7 day: 5.91m 12,900 ML/d
  • +8 day: 5.80m 12,500 ML/d
  • +9 day: 5.65m 11,900 ML/d
  • +10 day: 5.48m 11,300 ML/d
  • +11 day: 5.33m 10,800 ML/d
  • +12 day: 5.18m 10,300 ML/d
  • +13 day: 5.06m 9,900 ML/d
  • +14 day: 4.97m 9,600 ML/d
  • +15 day: 4.91m 9,400 ML/d

Nothing yet as of the 6th March.

  • Prior: -0.27m (0 ML/d)
  • Rising: 12:00 05/03/2020
  • Peak: 16:00 18/03/2020
  • +1 day: 5.64m 13,500 ML/d
  • +2 day: 5.61m 13,400 ML/d
  • +3 day: 5.55m 13,200 ML/d
  • +4 day: 5.47m 12,900 ML/d
  • +5 day: 5.36m 12,500 ML/d
  • +6 day: 5.25m 12,100 ML/d
  • +7 day: 5.13m 11,700 ML/d
  • +8 day: 5.02m 11,300 ML/d
  • +9 day: 4.91m 10,900 ML/d
  • +10 day: 4.82m 10,600 ML/d
  • +11 day: 4.76m 10,400 ML/d
  • +12 day: 4.73m 10,300 ML/d

Using U/S Weir 32 Gauge

  • Prior: 0.58m (0 ML/d)
  • Rising: 20:00 20/03/2020
  • First release: 1.33m 10:00 26/03/2020
  • Peak: 2.21m 17:00 01/04/2020
  • +1 day: 2.13m 3,200 ML/d
  • +2 day: 2.12m 3,100 ML/d
  • +3 day: 2.12m 3,000 ML/d
  • +4 day: 2.12m 3,100 ML/d
  • +5 day: 2.09m 2,900 ML/d
  • +6 day: 2.05m 2,700 ML/d
  • +7 day: 2.04m 2,600 ML/d
  • +8 day: 2.03m 2,600 ML/d
  • +9 day: 2.00m 2,400 ML/d
  • +10 day: 1.95m 2,100 ML/d
  • +15 day: 1.63m 800 ML/d
  • +20 day: 1.43m 400 ML/d
Pooncarie
  • Prior: 0.99m
  • Rising: 08:00 07/04/2020
  • Peak: 17:00 11/04/2020 (3.2m)
  • +1 day: 3.2m
  • +2 day: 3.2m
  • +3 day: 3.2m
  • +4 day: 3.1m
  • +5 day: 3.1m
  • +6 day: 3.0m
  • +7 day: 3.0m
  • +8 day: 2.9m
  • +9 day: 2.8m
  • +10 day: 2.8m
Burtundy
  • Prior: 0.51m (0 ML/d)
  • Rising: 10:00 11/04/2020
  • Peak: 14:00 15/04/2020 (1.75m / 1 2200 ML/d)
  • +1 day: 1.74m 2,140 ML/d
  • +2 day: 1.70m 2,070 ML/d
  • +3 day: 1.63m 1,990 ML/d
  • +4 day: 1.56m 1,880 ML/d
  • +5 day: 1.47m 1,750 ML/d
  • +6 day: 1.36m 1,590 ML/d
  • +7 day: 1.24m 1420 ML/d
  • +8 day: 1.11m 1,210 ML/d
  • +9 day: 1.02m 1,010 ML/d
  • +10 day: 0.96m 860 ML/d
Ashvale
  • Prior: 0.01m
  • Rising: 06:00 13/04/2020
  • Peak: 1.50m 16:00 16/04/2020
  • +1 day: 1.49m
  • +2 day: 1.45m
  • +3 day: 1.40m
  • +4 day: 1.34m

Other floods have shown even less predictable results, but in general:

  • The upper regions between Chinchilla to Warwick peak at a similar time and the water level drops off quickly (5 - 7 days).
  • St George peaks about 2 weeks after these towns, also showing a rapid drop after the flood.
  • Weilmoringle slowly peaks 2 to 3 weeks later as the water gets channelled out onto the floodplains, slow to drop.
  • Bourke may even peak before Weilmoringle, however the Darling River is primarily governed by the inflows from the Barwon River that accounts for ~70% of the inflow.
  • Flood waters arrive at Wilcannia about 2 to 3 weeks after Bourke, and 2 to 3 weeks later at Menindee.