Allow a minimum of three hours for this activity. 10 mins drive each way, 20 minute walk, then you can visit the Tin Dragon Interpretation Centre, the community museum and have a coffee at the Painted Door Art Cafe! Why not explore a little further... How to get there: From Tin Dragon Trail Cottages turn right onto the Tasman Highway. Drive up over the hill out of Branxholm. Continue on the Tasman Highway to Derby—about 8 km. Drive through the town and over the bridge. Find a car park on the side of the road. Take the lower (right) road for a short walk to the Derby Tunnel.
Look for the sign just over the bridge
Entrance to the tunnel
Recent earthworks reveal the start of the Cascade mountain bike trail. Across the deep river ravine several small houses perch precariously on the cliff faces—part of the charm of Derby. Terrific views for the mountain bikers, if they have time to see it! The tunnel was a mighty folly built in the 1880’s by one miner to move tailings beneath another miner’s lease. You will need gum boots and a reliable torch, because as the tunnel slopes downwards it fills with water. There are some unique inhabitants in the tunnel—the Tasmanian Cave Spider. The Tasmanian Cave Spider is the last of an old Gondwanan lineage of spiders. Back at the fork in the road take the top road. You can also walk up to the monument above Derby. Work off your indulgent morning tea. This gives a terrific view across Derby and into the now water-filled Briseis mine. The monument was erected for William Allan who died in Victoria in 1902.
The monument above Derby
View of the old tine mine site, from the Monument
Now follow the top road 2 to 3 km (4WD or walk) till the road condition deteriorates—stick to the top road, ignoring other small tracks. There are some interesting dry stone walls on each side of the track. What is their history? The track follows an irrigation pipeline, and I guess town water supply (Cascade irrigation scheme). Stop when the track deteriorates. Here the valley widens out. You’ll see an inspection point for the irrigation scheme. Walk into the gorge. You can see great sheets of moss and lichenencrusted granite rock with zigzagging streams of clear flowing water. This is the Cascade river gorge.
The mosses & lichens are reclaiming the granite
You are standing several kms below the (renamed) Cascade dam. In 1929 the old Briseis Dam failed after torrential rain, releasing a 30m wall of water and mud into this narrow gorge removing trees, rocks and soil, scrubbing the bedrock clean. Noticeable now are the alpine-like regrowth scrub and high tree-line.
Graham standing on a clean sheet of granite
Beautiful in the evening light The Cascade River Gorge
The flood was the worst in modern Tasmanian history lasting several days. Many buildings were destroyed and 14 people were known to have drowned. Nature is slowly repairing the damage. The Cascade Dam was rebuilt in 1936 covering an area of 49 hectares. You can read more about Derby’s mining heritage at the Derby community museum and the Tin Dragon Interpretation Centre. The inquiry into the deaths of those of the victims of the Briseis dam disaster whose bodies were recovered was concluded to-day before the district coroner (Mr. S. F. Evans) and a jury of four... from Advocate. Burnie Tas (Thursday June 20 1929). Read more
BRISEIS DAM DISASTER DEATHS DUE TO ACCIDENTAL DROWNING "No Blame Attachable to Anyone." JURY'S FINDING AT CORONER'S INQUEST. DERBY, Wednesday. Trove, Digitised newspapers and more. Advocate. Burnie Tas (Thursday June 20 1929) Accessed 26th April 2014 < http://trove.nla.gov.au/ndp/del/article/67822081 > The inquiry into the deaths of those of the victims of the Briseis dam disaster whose bodies were recovered was concluded to-day before the district coroner (Mr. S. F. Evans) and a jury of four. After a retirement of 35 minutes the jury returned a verdict that the deaths were caused through drowning in a rush of water down the Cascade River and over the Briseis mine workings, following the bursting of the Briseis Company's dam; and that the bursting of the dam was the result of an abnormal and unprecedented volume of water, which might have been caused by a cloudburst or by an extraordinary rainfall in the catchment. No blame was attachable to anyone. The jury comprised Messrs H. J. Rodman (foreman), B.W Turner, H. Harridge, and V. Davey. The inquest concerned the deaths of Raymond Whiting, Stephen Daly Whiting, Patrick Whiting, Samuel Brodley Cave, Hector Michael M'Cormack, Maxwell Whiting, and a person unknown, presumed to be Alice Whiting. Mr. Tasman Shields represented Mr Lindesay Clark, manager of the Briseis Tin Mining Co; Messrs. G. W. Waterhouse and V. C. Hall the Briseis Co, and Mr Jas M'Donald the A.W.U. and its members. Inspector Donohue conducted the case on behalf of the police. Mr. W. H. Williams, Inspector of Mines, was present on behalf of the Mines Department.
Recovery of Bodies William R. Taylor, sergeant in the Tasmanian Police, Force, stationed at Derby, said that about 4.30 p.m. on April 4 an avalanche of water came down the Cascade River and the old Briseis workings, taking all before it. As the result of the water, 14 persons lost their lives. After the water had subsided, search parties were organised, with the result that certain bodies were recovered. On April 6 the body of Raymond Whiting was recovered from beneath Inverarity's house. On April 8 the bodies of Stephen Daly and Patrick Whiting were recovered from the water now covering the workings of the Briseis mine. On April 15the body of Hector Michael Mâ€™Cormack was recovered from the Ringarooma River, about 5 miles from Derby, downstream. On the same date the body of Samuel Bradley Cave was recovered from the Ringarooma River, on the opposite bank behind the Dorset Hotel, Derby. All the bodies were removed to the Federal Hotel, Derby. Here they were examined by Dr. Jones. Maxwell Whiting's body was recovered from the Ringarooma River, near Moorina, on April 21. To Mr. Shields: On several occasions he saw the dam being constructed. Some of the workmen were trucking out and others were barring the stones into position. The weather on April 4 was abnormal and unprecedented.
To Mr. M'Donald: The trucks of stone for the dam were loaded with an engine. The small material was lifted by hand. He did not see shovels used, except in the mixing of concrete. To Mr. Shields: There were some very big stones at the back of the dam, up to six, seven or eight tons, and running down to small ones.
Woman's Body Under Debris Trooper Freiboth, stationed at Moorina, said on May 4 last he received information from George Honey and Cecil Roseberry, both of Herrick, that on that afternoon, while prospecting in the Ringarooma River, about 3 miles above Moorina, they discovered the body of a woman under a heap of debris along the bank. Next morning, May 5, he got a party of men together and proceeded to the spot. After some hours' work in removing logs and rubbish, the body of a female adult person was discovered. The body was examined by Dr. Jones. lt was beyond identification, and was conveyed to the Federal Hotel, Derby. George Arthur Jones, duly qualified practitioner, residing at Derby, gave details of his examination of the bodies and the cause of death, which in each case he attributed to drowning. Police-Inspector Donohue said this was all the evidence the police had to offer.
Dam Soundly Built Mr. Williams asked permission to call a witness, and called James Allen Hudson, Chief Inspector of Mines, who said his duties called him to all parts of the State. He was conversant with the Cascade dam, and had visited there since the flood. He visited the dam in 1924, just after it was commenced, and again in 1926, in company with Mr. Clark, the general manager, and the District Inspector of Mines, Mr. Curtain. The rock-filled section of the dam was being constructed. He went especially to make an examination of the conditions and deal with the details of construction. Mr. Clark explained fully all details, and, on making investigations and enquiry, he found the practice being adopted was a standard one, and no objections were made to the construction of the dam on behalf of the department. Mr. Williams: You were perfectly satisfied at the time that the dam was a perfectly safe structure? I had no reason to find any fault, with the stability of the structure. Continuing, witness said early in 1926 he visited the dam with Mr. Curtain.lt had been filled with water and was overflowing, which had no effect on the filling. He found the work then carried out was as agreed upon. He saw no detrimental effect to the wall of the dam as the result of the overflow. He confirmed his previous opinion that the dam was a safe structure. He arranged for Mr. Curtain to keep the dam under observation as to the effect the overflow would have on the rock filling. He found no material alteration. In 1927 Mr. Curtain reported that the dam was completed and that he was satisfied it was sound. Mr. Williams: At any time since the construction of the dam have you received any complaints regarding its stability? - No, nothing at all. To Mr. Shields: If there had been any doubt as to the safety of the dam, it would be the inspector's duty to report it. As the result of an inspection made after the flood, he came to the conclusion that something abnormal had happened on the watershed to burst the dam. The fall of the waves over the rockwork was, in his opinion, what had occurred. If there were two waves above the dam, each one would affect the rock filling. These waves indicated a cloudburst. After the dam was completed, if there had been any doubt as to its stability, the department would have taken action.
To Mr. Waterhouse: He would say that the dam was constructed to withstand any conditions that had previously existed.
Effect of Cloudburst To Mr. M'Donald: Our duty is to see that the construction is safe for the men employed, and for the general public. A cloudburst would bring water in one surge, and have a very marked effect on a dam of that type. It was a question of the discharge of water going over the spillway to the rock filling. There would not be the same effect in the flow of water from an abnormal rain as from a cloudburst. Mr. M'Donald: One witness said yesterday there was a boom put further up the dam for logs. Did that suggest that logs were likely to come down? It is always a safe practice to put in a boom. A log going over the spillway might dislodge the stones on the hill. In my opinion, the back of the dam went first. I attribute it to a surcharge of water, and am inclined to think that the dam did not go in one break, but in two waves. Mr. M'Donald: Do you think there was sufficient projection to hold the rock filling? - I came to the conclusion that it was sound. Mr. M'Donald: We can all be wise after the event. Would you say it would be safe now? I am inclined to think that where the dam was put the stone was rough. At present, it has the appearance of being planed off.
To the Coroner: I do not consider the bursting of the dam was a reflection on the department. The responsibility was the manager's. The department accepts no responsibility for any accident that may take place. In his address to the jury, Mr. Shields said that all realised they were engaged in a painful task. It was a matter of how, when, and where these people met their deaths. lt was clearly established that, the tragedy was caused by a rush of water in the Cascade river bursting the dam. They had to investigate the question whether there was any negligence so far as the construction of the dam was concerned. The evidence of witnesses showed that the carrying away of the dam had been very sudden. There was no gradual wearing away of the rockwork through the surcharge of water coming over the top. Leakages in a rock-filled dam were no indication of weakness. The dam had stood for a considerable time, and on many occasions water had flowed over the top without injury. They had the evidence of witnesses that the conditions were abnormal and unprecedented.
Construction Work Passed The construction work of the dam had been passed by the Mines Department, and had there been any indication of weakness it would have been reported. The explanation of the trouble was a cloudburst, which brought an abnormal quantity of water down the valley in waves. The water passed over the top of the dam, and dislocated the stone, causing the first wave referred to in the evidence, and when the dam collapsed the second wave came. The strongest dam might collapse under conditions which no-one could foresee at the time it was constructed. In fairness to Mr. Clark, he would ask the jury to find that the dam was constructed to meet all normal claims, but either owing to a cloud burst or to the abnormal and unprecedented rain it gave way. Mr Clark had been under a great strain. Whatever care he might take and whatever diligence he exercised when something abnormal happened, as in this case, causing the loss of so many lives, the strain was necessarily painful to him.
Mr. Waterhouse said that although perhaps the proper scope of the inquest was to find out whether there was criminal negligence, the company thought it best to put all its cards on the table, and allow the inquiry to take place without any limitation at all. The company felt that every opportunity should be given for the fullest investigation. The evidence showed, that the dam was properly constructed, having due regard to all the circumstances and happenings that, could have reasonably been foreseenâ€”although fall of rain on April 4 and 5 was unprecedented. Nothing like it had happened in the district before. It was not the duty of the company to provide for anything that might happen, but, to guard against what might reasonably be expected to happen. The dam collapsed about 4.30 p.m. There was no evidence to show how much water was going over the top before it burst. There might have been five or six feet.
Burst from Top Boon in his evidence spoke of an impression that the dam burst from the bottom, but the evidence generally showed that whatever caused the dam to fail was something which came over the top. He submitted that the whole evidence pointed to a cloudburst or an unprecedented fall of rain. Mr. M'Donald said he would have preferred to have allowed the evidence to go to the jury without comment. The point raised by Mr. Shields that the work was passed by the Mines Department should not, influence the jury, if there was any remissness or misjudgement by the officers of the Mines Department they had to take their share of the responsibility, the same as anybody else. The Coroner: They say they do not. Mr. M'Donald: I mean so far as the finding of the jury is concerned. He continued that there was only one roar, and it could not be established that there were two waves. Mr Shields had evidently lost sight of the evidence of Boon when he said that the dam shifted in one mass. Mr. Shields: I am afraid you donâ€™t understand. Mr. M' Donald: There is either something wrong with my misunderstanding Mr. Shields: Don't go any further; I will accept that. (Laughter.) Mr. M'Donald, continuing, said there was a good deal of supposition about the theories advanced. There was some supposition with regard to cloudbursts. Probably a person looking on would not be able to tell whether the whole of the dam was moving at once. He did think it most likely that a section would first give way. Mr. Waterhouse had pointed out that the company could not provide against what could not be foreseen. That was all right within reason. It was true they were wise after the event, but when the facts stared them in the face they could not lose sight of the point that in huge structures like this the construction must necessarily be of the safest kind.
Weakened by Water The only probable solution was that the fall of water displaced the stone sat the back, and weakened the structure. He regretted the circumstances of the inquiry, which were very sad from every point of view. There was no doubt as to the cause of death. He appreciated the reference made by Mr Waterhouse to the fact that, the company did not desire to raise any objection to the fullest inquiry. He did not think anyone would suggest there had been criminal negligence. They should learn from failures made in the past. If they found something had been done that had been a failure it was their duty to make such use of that evidence as would prevent a recurrence in the future. The coroner briefly addressed the jury. He said the expert evidence showed the dam was in every way properly constructed to resist any normal strain.
Jury's Verdict The jury, after an absence of 35 minutes, returned the following verdict: That the deaths were caused through drowning in a rush of water down the Cascade River and over the Briseis mine workings following the bursting of the Briseis Company's dam; and that the bursting of the dam was the result of an abnormal and unprecedented volume of water, which might have been caused by a cloudburst, or by an extraordinary rainfall in the catchment. No blame was attachable to anyone.
Cascade River 85 years later
After enjoying the quirky shops of Derby, take a short drive over the bridge to Tunnel Road . A short exploration here will show you how Der...