Is the Daly getting shallower?
- Matt Flynn
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Is the Daly getting shallower?
Had a long-time Nats competitor tell me the Daly seemed to be getting shallower.
It is possible for this to happen, with land clearing. Or is the Daly the same as it ever was?
It is possible for this to happen, with land clearing. Or is the Daly the same as it ever was?
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- Jedi Seadog
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Re: Is the Daly getting shallower?
No, every year is different and rivers will change with the season.
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- Seadog
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Re: Is the Daly getting shallower?
They havnt had rain down there for ages so its just the normal dry season height but it prett nasty on a low tide with all the logs etc
- theodosius
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Re: Is the Daly getting shallower?
I'd be surprised if bank erosion from boats was anything compared to a billions of litres of floodwater each year. Deforestation has to be having an effect though
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Re: Is the Daly getting shallower?
Changes in the environment have in the past been studied over a considerable time period, a knowledge base line is established and a consistent method of observation conducted. Conclusions are then made.
Our knowledge base line and methods of observation of the river don’t have these scientific factors. We are reliant on a mix of historic information and recent observation.
Firstly the historic information, the Daly River pioneers were serviced by boats from Darwin, there were a couple of wharfs established in the river, one near the Wooliana area and another closer to the old Robbie’s sand bar store where a railway from the Copper mine loaded out the ore for shipment to Darwin. This service continued until around the end of WW2. Large scale land clearing in the river catchment had not yet begun.
The vessels were large timber freighters, they undoubtedly moved in and out of the river on the tides, there is little information on these vessels or the schedules kept, the skill and the knowledge of the skippers and crew had to have been excellent to navigate the river, particularly during the dry season. However there is no mention of running aground or shipwrecks in the river.
The old method of sounding out water depth with a weighted rope to find channels was laborious and only documented in the vessels charts and for commercial reasons probably guarded information.
In recent times its only recreational vessels plying the river. The number of boats gradually increased over the past 20 year period along with the use of depth sounders, it’s reasonable to think that skippers don’t keep logs of river depths. They might remember changes in depth over small areas that they fish or navigation hazards that vary from year to year some of which end up on GPS memories.
Over time the river changes, particularly in the lower reaches where the tidal influence is conflicting with the outflow of the river, the delta is a dynamic area that experiences tidal pumping where sand is pushed into the river mouth and river outflows cut narrow channels that are rarely permanent.
The impacts we have on the river are probably understated, large scale land clearing, introduced hard footed animals and invasive weeds all contribute to negative changes in the river.
To think that waves that pound a river bank that evolved having never experienced waves over millenniums doesn’t have a negative impact on that river bank is an example of not only denial but stupidity.
On a scale of things my brief time on the river and observations of the river doesn’t carry any scientific credibility. However I do see change and have photos and videos of the river environment taken over 28 years that show that change.
Given that the volume of water coming and going out of the river is fairly stable, if it is getting shallower then the mathematics demand that the river must also be getting wider to accommodate that water, perhaps that’s why floods are occurring more frequently.
The causes and reasons don’t really matter to me and I believe that even if we were to take action and try and stop these changes the damage is done.
Do I think the river is getting shallower? Yes.
Our knowledge base line and methods of observation of the river don’t have these scientific factors. We are reliant on a mix of historic information and recent observation.
Firstly the historic information, the Daly River pioneers were serviced by boats from Darwin, there were a couple of wharfs established in the river, one near the Wooliana area and another closer to the old Robbie’s sand bar store where a railway from the Copper mine loaded out the ore for shipment to Darwin. This service continued until around the end of WW2. Large scale land clearing in the river catchment had not yet begun.
The vessels were large timber freighters, they undoubtedly moved in and out of the river on the tides, there is little information on these vessels or the schedules kept, the skill and the knowledge of the skippers and crew had to have been excellent to navigate the river, particularly during the dry season. However there is no mention of running aground or shipwrecks in the river.
The old method of sounding out water depth with a weighted rope to find channels was laborious and only documented in the vessels charts and for commercial reasons probably guarded information.
In recent times its only recreational vessels plying the river. The number of boats gradually increased over the past 20 year period along with the use of depth sounders, it’s reasonable to think that skippers don’t keep logs of river depths. They might remember changes in depth over small areas that they fish or navigation hazards that vary from year to year some of which end up on GPS memories.
Over time the river changes, particularly in the lower reaches where the tidal influence is conflicting with the outflow of the river, the delta is a dynamic area that experiences tidal pumping where sand is pushed into the river mouth and river outflows cut narrow channels that are rarely permanent.
The impacts we have on the river are probably understated, large scale land clearing, introduced hard footed animals and invasive weeds all contribute to negative changes in the river.
To think that waves that pound a river bank that evolved having never experienced waves over millenniums doesn’t have a negative impact on that river bank is an example of not only denial but stupidity.
On a scale of things my brief time on the river and observations of the river doesn’t carry any scientific credibility. However I do see change and have photos and videos of the river environment taken over 28 years that show that change.
Given that the volume of water coming and going out of the river is fairly stable, if it is getting shallower then the mathematics demand that the river must also be getting wider to accommodate that water, perhaps that’s why floods are occurring more frequently.
The causes and reasons don’t really matter to me and I believe that even if we were to take action and try and stop these changes the damage is done.
Do I think the river is getting shallower? Yes.
- Matt Flynn
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Re: Is the Daly getting shallower?
281 views and only 11 votes, thought there would be more on here who have fished the Daly long enough to notice trends
- b-radical
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Re: Is the Daly getting shallower?
Only fished the daly 4 times (on boat dry season) so haven't seen it enough to know although can anyone vouch that the narrow parts are deeper and the wider stretches shallower??? just something i was told when i stayed at Wooliana a couple of years back
- theodosius
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Re: Is the Daly getting shallower?
Lucky some blokes put floats on the snags, looking shallow again this year at browns and a few other spots based on footage I've seen
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- Jedi Seadog
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Re: Is the Daly getting shallower?
A river that floods 14 plus meters of water through it every other year is gonna change. Even as a kid the river was full of timber, sandbars, rockbars ect and a boat over 4m with a 20hp was a dream boat. A river with such flow is gonna widen in parts and narrow in others. I fish upstream a bit and it doesnt see nearly the boat traffic of the down stream section and it has huge collapsed banks ect. I find it rich to believe that boat traffic is adversly affecting the banks. The river naturally meanders and sediments that are torn off one outside corner are deposited on the inside eddie of the next and the process and river evolution continues. Trees eventually grow on the sand bars on the inside bends while others collaps into the river on the outside bends ect
. I dont doubt that land clearing and bores upstream to grow water thirsty crops will have an effect on the springs during poor wets but while we are having decent wet seasons the current amount wouldnt have an effect this early in the season in my view as the water table should be high.
. I dont doubt that land clearing and bores upstream to grow water thirsty crops will have an effect on the springs during poor wets but while we are having decent wet seasons the current amount wouldnt have an effect this early in the season in my view as the water table should be high.
- STANDY
- Jedi Seadog
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Re: Is the Daly getting shallower?
Funny as was in a boat a few years ago with a older guy that has a old chart plotter. Funny to see the change in the tracks used in the river on a 10 year old chart plotter ( low tide )
Rivers change and a few big wets can as above move corners profoundly.
Just lucky we have water unlike SA
Rivers change and a few big wets can as above move corners profoundly.
Just lucky we have water unlike SA
A Fish in the Boat is Worth Five in the Shop.
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- Seadog
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Re: Is the Daly getting shallower?
You have only got to look at the mouth of Bamboo Creek, I has changed a lot in the last 5 years!!!
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- Jedi Seadog
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Re: Is the Daly getting shallower?
Plenty of water in Browns Creek looking back towards the Daly (snuck in for a day between the comps)
At least parts that are noticeably shallower are sand build up - unless the rocks are rising too
Hull and skeg damage completed
At least parts that are noticeably shallower are sand build up - unless the rocks are rising too
Hull and skeg damage completed
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- b-radical
- Seadog
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Re: Is the Daly getting shallower?
Could have a game of golf on that island now plenty of green
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- Seadog
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Re: Is the Daly getting shallower?
Browns Creek is where the biggest change has happend.
The River is alot Wider, and seems shallower.
But, I can remember having a Bath on the Rockbar, on the RH Side, just before Browns, on Low Tide.
The Rockbar Now, where generally, it is obvious it is there, never appears to come out of the Water, like it did in the past.
From memory, it used to be exposed, by 30 to 50 cm.
Thinking about it more, the amount of erosion that has occured along that RH Side, where we used to Camp. along with a heap of Grey Nomads, that stayed there for 3 - 6 Months, the Rockbay that is there now, would have mostly been covered with Dirt, and had Campers staying above it.
The Rockbar I am talking about, does not seem to exist Now.
If it was possible, it would be interesting to lay an Old Map, or Arial Photo, over the Current River.
By my recolections, the Current River Bank, must be atleast 50 Metres, away from where it was, when the Boat Ramp was first Made at Browns Creek, and only lasted 1 Season. (I wonder if NTG have Old Photoes, of that Boat Ramp, when it was made).
Back then, I was Coming up from Adelaide, for a Week or 2, and I think I only stayed at Browns, once or twice, before the Boat Ramp was made, and a few times after.
The River is alot Wider, and seems shallower.
But, I can remember having a Bath on the Rockbar, on the RH Side, just before Browns, on Low Tide.
The Rockbar Now, where generally, it is obvious it is there, never appears to come out of the Water, like it did in the past.
From memory, it used to be exposed, by 30 to 50 cm.
Thinking about it more, the amount of erosion that has occured along that RH Side, where we used to Camp. along with a heap of Grey Nomads, that stayed there for 3 - 6 Months, the Rockbay that is there now, would have mostly been covered with Dirt, and had Campers staying above it.
The Rockbar I am talking about, does not seem to exist Now.
If it was possible, it would be interesting to lay an Old Map, or Arial Photo, over the Current River.
By my recolections, the Current River Bank, must be atleast 50 Metres, away from where it was, when the Boat Ramp was first Made at Browns Creek, and only lasted 1 Season. (I wonder if NTG have Old Photoes, of that Boat Ramp, when it was made).
Back then, I was Coming up from Adelaide, for a Week or 2, and I think I only stayed at Browns, once or twice, before the Boat Ramp was made, and a few times after.
Sick of coming home Fishless
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- Platinum Member
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Re: Is the Daly getting shallower?
The Charles Darwin Uni study of the Daly River bank erosion has been released, seems the science is voting for a river that is getting wider and shallower.
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