I was more than surprised to see this section of the Clutha under claim for suction dredging and offered for sale on Trade Me. It appears to me as an attempt at real-estating! And because it looks like a real-estater is at work, anyone interested in the claim should first check with the ORC that there is an actual Resource Consent and that its written down in black and white that the use of an 8-inch dredge is permitted.
One thing is obvious from the start and that is that it would not be a fun claim for any recreational dredging. But as we don't usually concern ourselves here on this forum with recreational dredging, and as we have the emphasis on commercial scale dredging, I would say that it would be difficult to make a living, even with an 8-inch suction dredge. A 10-inch dredge might make a go of it ... but I would consider even that doubtful.
This section of the Clutha from Clyde down to Alexandria was a very easy to dredge river environment for the large number of bucket dredges that went through the Clutha over 100 years ago. And this section of the Clutha in particular was hammered more than any other by the large bucket dredges. Its far from being a hard and fast rule that if a bucket dredge has dredged a river then there is no economic deposits of gold left ... but, in this case, my guess is, that, bucket dredging did have a big impact because it was such an easy environment to bucket dredge. In a large and deep river one of the main ways previous bucket dredging makes it difficult for the same river to be re-mined today is that the bucket dredges loosened up all the gravel by breaking up any hard pack layers that had formed over hundreds of years (gold coming down the river would come to a rest on these hard pack layers to form a payable pay-streak that the bucket dredges mined). But with the river gravel loosened by bucket dredging the gold of some weight traveling along the river easily goes down through the lose gravel until bedrock is hit or it hits a hard pack layer that was too deep for the bucket dredges to reach.
Although there would be little chance of getting a Resource Consent, in my opinion the only efficient way to dredge the Clutha in this section, where it is so wide and deep, would be with a large floating excavator feeding a floating trommel plant (such as the ones currently being used in South America and like the one recently featured in the TV show about dredging at Nome, Alaska www.youtube.com/watch?v=ZX_UPeI_mSw ).
L&M Mining had a plant in the Kawarau river near Cromwell in the late 80s and they did not do particularly well. The plant they used was was one of the biggest ever used by L&M which was fed by the largest excavator (then) in the Southern Hemisphere ... so they sure had a big enough through put. The same plant operating today would probably be more economical because of the higher gold price ... however they only got a Resource Consent back then because the ground they worked was to be flooded when the Clyde Dam was finished.
Back in the 90s just below the Clyde Dam a large excavator operated for a while to deepen the river so the dam could operate more efficiently by getting the water away quickly. The excavator was floating and it would dig dirt from the active riverbed to dump into a barge which would then be floated down river and the river gravels dumped on shore, somewhere. Well, when the river gravels were dumped by the excavator into the barge a guy on the barge would scoop a sample of dirt and wash it with a gold pan to see if any gold was present. I doubt they would have found any likely prospects or they would have run the wash through a trommel plant rather than just dumping it.
I sent an inital e-mail to the claim owner, this is what I got back.
I have done very little work on the claim the only time i dredged was last september when i came back from aussie for a couple weeks (been living there for 3 years) and i assembled my dredge and had a go. the first time i spent 3 hours dredging which gave me 5 grams of mainly fine gold with 8 larger flakes, this was on a beach halfway down the claim, the next day i went to another beach and done 4 hours and got 4 grams this was a bit differnt tho as i had a blocked ear and couldnot put my head under so was limited to depth i could dredge. also these were the first time dredging in almost 5 years. i have also spent alot of time with a highbanker i can get colour the entire legnth of the claim in fine flood gold, some areas i can get a gram an hour shovelling on the banks and beaches. the best ive done with highbanker was 2.5grm for a little of an hour shovelling this was just below the bridge. the best thing to do if you are serious and want to see for yourself would be to take a dredge there yourself for a day or 2. as far as the dredging season is concerned you could dredge all year round if you have a hot water system or dry suit as the ORC permitted activity rule dose not have any restrictions on when you can dredge. if however you were to get consent for an 8 inch they may restrict you to months you can use it but it is mainly trout spawning that does this and there are not too many fish here so you may get all year with a 8 inch consent. the floding is a bit unpredictable due to the dams it is controlled quite well and that actual floods sometimes only happen once a year or even longer all depends on how long heavy rain can be held in the dam, the river rises and falls daily sometimes hourly due to power demand most times it will only surge or fluctuate aprox .5 m but there have been times when ive seen this riese well over a meter. about 4pm seems to be the worst time of day if you were on the edges or a beach these would hardly affect you.
thanks for your interest any more just ask.
For what it's worth. As sated by another memebr earlier, if you this way inclined to consider this claim, a visit to the guy would be a go, and as Rob states to ensure the Resource Consent is in place is of high priority (About as high as making sure there is actually gold there)
Last Edit: Jul 9, 2012 14:21:23 GMT 12 by nuggethead
When you want something done right, don't involve the government.
It would be worth while for anyone considering purchasing this claim to do some sampling work before parting with any money ... but they would need much more than 2 days! And the sampling dredge used would have to be set up for extremely fine gold, and as there would be massive amounts of the typical Otago heavy black sands, the dredge sluice box would need to be set up to cope with the black sand.
Its in the claim owners favor that he would let prospective buyers on for some sampling. Letting buyers on claims for a sampling program is something other claim owners will have to be more willing to do in future if they expect to sell their claims.
Judging from what the claim owner has written it appears to me that there are no Resource Consents, and if that's the case, the dredge size would be limited to a 6-inch dredge. A 6-inch would be OK for a sampling program but because its such a massively wide and deep river over the claim any production dredging would need to be carried out with a larger dredge. There is a good chance an 8-inch dredge would eventually be permitted as the river is so large. But it could take years and cost a great deal of money to go through all the hearings before a production dredge enters the water.
The best person to buy such a claim would be someone with a great deal of capital who is looking for a long term dredging proposition, using dredges up to 10-inch and maybe larger. Such a dredging project would be costly before seeing any gold and it would need a team of experienced dredgers for it to be successful. And there are probably better large NZ South Island rivers with more of a chance of success.
Also, for most of the year there is a great deal of turbidity coming down the Clutha from the Shotover catchment. The divers would be working blind most of the time with a loss of efficiency.
The other claim that the Clutha claim owners have is the Waikaia from Canton right up on the Old Man Range to near Potters. The way they have the claim surveyed is bizarre as about half of the active river bed is out of the claim boundaries. A member of this forum once had a dredging claim on the Waikaia in the same spot ... if we are lucky he might make a comment.
Post by forestranger on Jul 9, 2012 16:51:26 GMT 12
Rob we indeed did have this part of the Waikaia River under claim, and did extensive testing from the Canton right up to potters, but found no commercial quantities of gold. We had our own helicopter in those days so moving gear was not a problem. Danny Walker also worked in the gorge below the Canton with similar results..
Did a lot of work in the Clutha over the years and the bit between Clyde and Alex is not a piece of ground we would ever bother to look at.
Thanks for letting us know the results of your prospecting in the upper Waikaia! Its a river that has everything going for it ... except payable gold deposits :(. It must have been nothing short of the worst result possible for you after going to the extent of flying your gear in there by chopper (and the way that ended). The only explanation I can suggest for the lack of gold is that the river up there must be shallow, permitting the old timers to hand mine it extremely thoroughly. I've walked most of the Waikaia up from the Canton bridge to near Potters, and there are some impressive wing dams remaining in the river bed.
I noticed someone has been reckless enough to put a claim in the steep gorge area of the Waikaia below the Canton bridge. I remember the time when you and Danny floated down from Canton bridge with only wet suits to keep you buoyant. And since then a few canoeists have lost their lives when caught in the gorge during a flash flood. Putting a dredge in there would be madness.
The other claim that the Clutha claim owners have is the Waikaia from Canton right up on the Old Man Range to near Potters. The way they have the claim surveyed is bizarre as about half of the active river bed is out of the claim boundaries.
Think you mite have your wire,s crossed there rob ? as this calim 54375 ...is not the same as the canton claim. which from what i can see has the boundary's spot-on along the river if anything a bit of over kill...maybe enough room for a bulldozer to push all the gold into the river ;D ooo i can hear the rma people crying already!!
I no the fella selling the clutha claim he,s a straight up dood if you had any questions or wanted to actually have a look at the place/dredge i cant imagine it would be a problem at all iv been tempted to have a look my self but unfortunately haven't had the time. Phill.
No, I have the right permit. Below are some screen shots which show black lines which I interpreted as the boundary lines. Are the black lines the claim boundary, or is the boundary marked by something else?
Hi Rob yes i see what you mean now though on the main gis view it doesn't look like that....the maps do seem to vary a lot aye like the 1 i quoted 54375 man the creek is a long way off in places!! Cheers Phill.
All I can think of is that it is a mechanical issue. Possibly, because its being done on a computer with software, it can only draw straight lines. Before computers a person would just draw the lines on a paper map to follow the river bank that is already marked on the map. It probably says in the specifications of the claim that it is exclusively the riverbed that is to be mined. And in that case its only the start and finish of the claim that is critical.
I've found some more of my photos showing historic remains from river mining. The first four are of wing dams in the upper Waikaia river on the Old Man Range. Another is of a river diversion in the far upper Waikaia river (above the claim in question) and the last photo is of a river diversion in another part of the Old Man Range.