A look at the current flows along key rivers
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
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
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
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.
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!
From Dalby down, there was a bigger rain event in their catchment.
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.
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
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
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.
Peaked at 17/03/2020 11:00 (5.49m), 1cm below moderate flood. Peak travelled at 1.2 km / hr from Dalby.
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.
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).
Level of 0m increased to about 5m from 28/02/2020 02:00 over a number of days.
Nothing yet as of the 6th March.
Using U/S Weir 32 Gauge
Other floods have shown even less predictable results, but in general: