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EAST BAY NECK CANAL
THE OPENING CEREMONY.
SPEECH BY THE GOVERNOR.
DESCRIPTION OF THE WORKS.
(By Our Special Reporter.)
At last the East Bay Neck Canal at Dunalley has been formally opened. The ceremony was performed yesterday by His Excellency the Governor, in the pre sence of a very representative gathering, including the Ministry and a Parliamen-
With the exception of Coode's Cut on the Yarra, close to Melbourne, this is about the biggest "ditch" in Australia, serving to connect two seas, namely the open ocean on the East Coast, entered through "The Narrows" from Black man's Bay, with that magnificent sheet of water on the western side of the Peninsula, called Norfolk Bay, where the Australian squadron sometimes goes to manouvre. It was designed by Mr.
Napier Bell, and adds one more to the triumphs of his engineering skill. The contractors were Messrs. Knutson and Henrikson, who have carried out, and have now in hand, numerous public works in Tasmania, notably the East Devonport training wall, Stanley break water, and Tasman Island lighthouse. As
to the canal contract, however, it is fear- ed the firm have made little, if any, money by it, but it is acknowledged on
all sides that they have done their work exceedingly well. During the term of office of the Hon. Edward Mulcahy as Minister of Lands and Works, Parlia ment authorised a vote of £20,000 under
64 Vict., No. 63, for the canal, and Mr.
C. Napier Bell, M. Inst. C.E., was in- structed to prepare the necessary plans and contract for the construction of the canal to connect Norfolk and Blackman Bays, in order to save a distance of 40 miles through rough water in the jour noy to the East Coast ports. Tenders were invited in all the States and in New Zealand, and on September 25, 1901, eight were received, ranging in amount from £17,779 9s. 11d. to £23,879 7s. 4d., and the lowest - that of Messrs. Henrikson and Knutson - was accepted, and contract signed on November 29, 1901, fixing date for completion on May 29, 1904. Some delay was caused before work was start- ed in endeavours to procure a more powerful plant to expedite the work, and which should subsequently become the property of the Government for general use in the State ; but the proposed ar rangement fell through, and the excava tions below water were eventually taken out with a steam navvy. The canal, in cluding the approaches on either side, is 1½ mile long, 10ft. deep at low water, and 56ft. wide at surface of low water, with 16ft. width at bottom in canal proper,
and 30ft. wide at bottom in approaches. Greatest width at surface of cuttings through the neck, 105ft.
The canal enables vessels between the East Coast and Hobart to take a short cut through smooth water, without going round the stormy waters of Cape Pillar, thereby saving, as already mentioned, about 40 miles. The sea now runs through the canal between the two bays, the cutting between the high banks, ex tending about a mile, presenting a strik- ing spectacle, amid peaceful rural sur- roundings and bold scenery, including the lofty hills and dense forests of Forsetier's Peninsula. Standing on the hotel side, and looking across from bank to bank, one begins to realise what an imposing waterway it is. Even the Suez Canal in its clear run parts only averag- ed at bottom 25 yards until lately, when it was made a few yards wider in
The contractors found it a pretty for- midable undertaking, the enormous amount of "waste" that had to be shifted
in connection with the excavations, totalling 171,864 cubic yards, with an
other 30,000 cubic yards at the Norfolk Bay approach, and at the Blackman's Bay end 19,000 cubic yards. The material consisted of red clay, gravel, pipeclay, and some rock. Contrary to expecta-
tions, the contractors found the material, in places, much stiffer to shift than was anticipated. They struck a bar of iron stone rock towards the Blackman's Bay end, but it fortunately proved to be a narrow and not very deep stratum, though the removal of about 2,000 yards of it became necessary. The highest part of the excavations is about 18ft. above low water mark. During strong tides there is a rise of about 6 ft. of water in the canal, about 4 ft. being the average, and it is reckoned that a vessel drawing 13ft. will be able to pass through on an or- dinary tide. Steamers can steam through, but sailing craft, unless favoured by suit able wind astern, require to be towed. The pipeclay in the embankment on both sides shows signs of fretting away in places between high and low water mark; but this is not regarded as a very serious matter, as the wash of the waterway will carry off the material; and should the fretting, in time, cause the slopo of the cutting to slip, it will then assume, at such places, its natural slope. Any im- pediment to the navigation of the canal on this account at any futuro time may, if it arises, be easily removed with a dredger.
The first dredging plant used having proved insufficient to cope with the ex tremely tenacious material, the contract- ors mounted a Rust and Proctor steam navvy on a barge, which acted very effectually, whilst the dry excavations, amounting to nearly 172,000 cubic yards, were taken out by an engine and trucks, and run on to dumping grounds on the shores of each bay. Portions of the
stuff below the level of the water were taken out by the steam navvy acting as a dredger.
As to the additional dredging rendered necessary in the waters of Blackman's Bay on the route across to The Narrows
and the open sea, these have been carried out at an additional cost of about £2,000, and now the Marine Board, who have taken over the control of the canal, have a marked channel right through the bay and The Narrows into the open ocean. The work involved cutting through shoals at the northern end of Blackman's Bay for a length of 26 chains, and to a depth of 6ft., in order to give the same depth below low water as in the canal proper. This channel is 50ft. wide, and 29,000 cubic yards have been taken out with the
contractors' special plant.
The canal, with its high sloping banks, looks quite imposing, having a sweeping bend in it, which was necessitated to avoid much deeper cuttings through higher ground. At the Norfolk Bay end a sub- stantially constructed wharf or "dock," as they locally term it, has been put up, that will eventually succeed the very long jetty for Dunalley. Just above the en- trance to the canal from this side, it is spanned by a swing bridge with an open ing of 30ft. in connection with the thor oughfare from the Carlton and Bream
Creek roads to the Dunalley Hotel and places beyond. The bridge opens and closes on a pivot, which works on a cen- tral concrete buttress or pier, and cost about £1,300. The whole of the iron
work in the swing span of the bridge was manufactured in Launceston by the Salisbury Foundry Co., who erected it in its present position. At the Blackman's Bay end the canal banks taper down to
the water's level. This bay is a fine sheet of water, almost landlocked, surrounded by picturesque scenery, and is noted for its flounder fishing. The dredging operations at certain points across it to The Narrows became necessary through the existence of several sand banks. A wide channel as much 40ft. deep has been secured, in accordance
with very carefully prepared hydro graphic surveys made and soundings taken by Mr. Wherrett, the Government representative and engineer on the works. The Marine Board's harbourmaster has staked and marked the course for navi-
The people of the district are jubilant over the success of the undertaking, especially when they recall the carping criticisms of pessimists who, unmindful of the saying that a little knowledge is a dangerous thing, predicted failure through sand bars and other difficulties, which predictions have not been fulfilled, the "scour" of the tides in the canal tend- ing to keep the sand "alive" at both ends, as Mr. Napier Bell concluded it
would. At any rate, it is now the opinion of the Engineer-in-Chief that any maintainance in the way of dredging will be very small, and confined to "the outer ends of approaches." Already vessels have been glad to put back from Cape Raoul to the calmer waters of Norfolk Bay, and take the canal passage instead. It is claimed that the canal will prove an incalculable benefit to the East Coast. Produce and live stock will be far more expeditiously taken through to Hobart, and the fishing industry will find it a great convenience. Last month the bridge was opened for vessels to pnf-s through no less than 104 times, and this number is exclusive of fishing boats, which lowered
their masts and passed under it. The canal affords facilities for the finest yachting cruise to be had in the Southern hemisphere.