HALF-WAY THROUGH

Dominion, Volume 16, Issue 170, 6 April 1923, Page 9

HALF-WAY THROUGH

ORONGORONGO TUNNEL. Mr. Barrance, engineer for the City Council at the Orongorongo tunnel works, reports that of tho total length of 10,494 feet which will have to bo penetrated, a distance of 5645 feet had been cut up till a week ago- -and the work is proceeding steadily from both the eastern and western faces of the range. On the western side, entering the"hill from George's Creek in the Wainui Valley, a-distance of 3830 feet has been bored; while from the Orongorongo Stream side, where operations •were commenced about twelve months later, the tunnel has been pierced to a distance of 1815 feet. Evidence, of the pace at which the work is being carried forward is afforded by the inct that since the beginning of last November the partV of co-operative fny- ’ nellers, which is responsible for the big contract, has cut a total of over -OyO feet into the hard rock which forms tho backbone of the Orongorongo Range, the face measuring 7 feet bv 7 feet. Very little timbering has been necessary on either side, as the “country is hard and hcaw almost throughout. At the Orongorongo Valley side tho construction of the dam and weir from which.the'water of the stream is to be diverted by nines through the. tunnel is being carried out by dav labour. This part of the work has nothin" to do with the contract let to Mr. Femnlo find his party of miners. Iho dam proper has not vet been commenced, hut. the necessary excavation in the bed of the stream and for the reinforcement of the banks is well under way, and will soon be ready for the recept:on of the concrete. At tho side or stream jv weir has been formed, into which tho water will flow through narrow apertures behind the dam. Small holes in the' concrete flooring will lead the water into the 21inch pipes that will connect up with the Morton Dam on the other side of the range. The actual boring operations were commenced late in 1920, and the contract proper was begun some months prior to that, but. the preliminary work was necessarily confined to the pitching of camps, the making of roads, etc., and progress was comparatively slow until mechanical means of boring were available in September, 19.21. Power-driven drills are now at both of the tunnel, and the contract is being pushed on without hindrance. , . It is anticipated that the work will be completed by next Christmas.