8. The main feature of the new Waterworks is the granite masonry and concrete dam which it is intended to build across the Tytam Valley for the purpose of stopping the waters that find their way into the valley. This dam, which will be 110 feet high in the centre, will form a lake of nearly 30 acres with a maximum depth of 105 feet and will contain 300 million gallons of still water supple- mented by daily reinforcements of running water from the tributary streams that flow into the valley, and the aggregate yield of which is estimated at about 130,000 gallons a day.
9. The impounded water of the new reservoir will be issued at a level of 400 feet above the sea, a height sufficient to include nine tenths of the houses in Victoria, leaving the small residue of dwellings situated above this level to be supplied from the Pokfoolum couduit which runs along the 500 foot parallel.
10. The presence of an intervening range of mountains between the proposed new reservoir and the town has rendered necessary a tunnel for the passage of the waters to the Victoria side of the ridge. From the outlet of this tunnel which overlooks the Wong-nei-ch'ung valley, the Tytam water will be brought into town, a distance of nearly three miles, through a masonry surface conduit following the hill contours in the same inanner as the present Pokfoolum conduit.
11. The total length of the tunnel is about 7,300 feet. It is being driven from both sides of the mountain without the assistance of any intermediate vertical shaft, with the intention of meeting somewhere near the middle. The boring is being conducted by percussive machinery driven by compressed air, and the explosive used is exclusively dynamite. Operations were begun on the Tyram side of the mountain in April and on the Victoria side in July of last year (1883); practically, therefore, the tunnelling has been in hand now about one year, and a length of fifteen hundred and thirty feet has been completed, or a little over a fifth of the whole. From the beginning the work has been kept up under continuous pressure, men and machinery working without intermission through the night, as well as by day-time, the watches or shifts relieving each other every eight hours.
12. The extraordinarily hard and unfavourable nature of the rock traversed, no less than the many minor difficulties that necessarily beset so heavy an undertaking as this in a country so far removed from the many facilities and advantages enjoyed by similar works nearer home, have tended to retard progress during the first year of the initiation of this work, but it is confidently anticipated that the substitution of the heavier driving machinery shortly expected from England will greatly accelerate speed and enable the miners in the two headings to effect a junction by 1887.
13. The masonry dam, outlet-works, and bye-wash, it is expected will be finished by 1886, but although the new reservoir may perhaps be ready for use a year or more before the tunnel, it will not be possible to avail of the impounded water until the completion of the tunnel unless steam-pumping operations are resorted to, in order to pass the water over the ridge from the Tytam to the Victoria side. The temporary expedient of steam-pumping may prove of advantage in the event of the heavier boring machinery shortly to be used not answering to the fullest, the expectations formed of it, but this is a point that it would be premature to discuss until that machinery has been tested.
14. Fully Eighteen months, however, before the completion of the tunnel the present deficient water supply of the town may be increased to some extent by means of the proposed conduit from Wong-nei-ch'ung to the Albany, (in the Upper part of the City of Victoria) which will be made to take in the contents of the nullahs met on the way and the aggregate yield of which (not including