THE CITY TRAMWAYS.

Otago Witness, Issue 2541, 26 November 1902, Page 14

THE CITY TRAMWAYS.

ADDITIONAL WATER-POWE& SCHEMES. THE BEPORTS OF MESSRS BROWNE AND STEWART. Messrs R. H. Browne, C.E., and R. T. Stewart, who were commissioned by the City Council to report on the proposals for bringing in the waters of the Lee Stream for the generation of electrio power, have concluded their investigations, and their report was laid before the Tramways Committee on Tuesday night. The report was as follows : — " In accordance with your instructions to investigate and report upon the several proposals already before you, to bring water from the Lee Stream to a point at or near the Taieri River for generating power for tramways and other purposes in Dunedin, also to devise, if possible, some better 6cheme for the purpose. "In acting on these instructions, the first point which we had to take into consideration was whether or not a sufficient quantity of water could be obtained from this source to meet your requirement, and, if not, can the supply be conserved so as to meet the demands in the dry seasons. We understand that the minimum supply required would be ,16 Government heads, and tho maximum from 30 to 40 heads. The next consideration was that the mode of conveying the water should be the one least liable to interruptions, and keeping this steadily in view we proceeded to investigate the various proposed routes place-d before you by the city engineer and Mr Anderson. THE CITY ENGINEER'S SCHEME. " We have the honour to report that after a caTcful investigation of the variou-3 points in connection with the scheme laid before you by Mr Rogers, we are agreed that the site selected^by him for a weir at the intake of his proposed line of race is eminently suitable for the purpose for which it was selected — i.e., to secure the water from the whole of the available watershed, including as it does Fortification Creek. The race line, however, as located by Mr Rogers, would pass over such difficult country as would not only entail a cost in conrtruction far beyond tho sum estimated, but what is of more importance, it would be practically impossible to maintain the same without frequent interruptions. We therefore condemn tho scheme as unsuitable for the puTpote for which it was intended. JfR ANDERSON'S SCHEME. " After thoroughly examining the different branches in connection with Mr Anderson's proposed routes, we are decided : (1) That the sites selected by him for storage reservoirs are admirable ones, but no scheme in which it was proposed to lift the water whore Mr Anderson propo^ to lift it would be in any scn«e complete without storage res. v rvoir=. (2) That Mr Anderson's proposed line of race, although the major portion of it would pass over tolerably good racecountry, so far as tho matter of construction is concerned, yet it would be of such a length a<3 \vou!d entail a considerable loss of water due to percolation and evaporation, besides being liable to interruptions in many places by slips, and because of its position for some distance on tho brow of the table land by snow drifts in winter. (3) Th« most vital objection to Mr Anderson's pclieme, and one which id sufficient, to condemn it, is that the intake of his proposed race would be pitualed in such a position in the watershed that fully two-fifths of the available water would be lost. We must therefore condemn this scheme also. " Havint* so far carried out your instructions to deal with the routea proposed by Mes^r* Rogers and Anderson, we turn our attention to your further instruction rcquirI inp; 'i. if possible, to propound a more , buital>!a sc!ieme. i THE PIPE SCHEME. We are agreed that better schemes than i those proposed by either Mr Andr-rson and Mr Rogers are possible. One of which, and one we could most highly rocomironc' — hid w© not discovered a hetter, —would be to construct a weir on Mr Rogers'* weir site to a height of 15ft, and to draw off the water !>y iron pipes 30in in diameter, plncod 10ft; below the cro=t of the weir, thence to con£9X ii ilu:ou£u pij^ta oi aiaukf w$ iat J4*

whole of the distance to near the mte of the power house ' C,' located by Mr Ander* son, on the Taieri River — a distance approxi< mutely of six and a-half miles, there being no engineering difficulties in the way of carrying out such a scheme*. The rnininvn-nrm power required would, except in extended" dry seasons, always be available, and tha probabilities of interruption, provided tha work was carried out thoroughly, would b« reduced almost to a minimum. The cost ofi carrying oufc euoh a scheme would ba approximately £25,000, or rather less. THE TUNNEL SCHEME. We beg to report that we have devised $ better scheme than, any yet referred to, and which we now specially recommend aa being the* least liable to interruption. This scheme is to start at Mr Rogers s weir site, or about 20 chains below it, as may be determined after survey, and to convey the water therefrom through a tunnel to the Missing Link Creek— a distance of 110 to 115 chains; — thence through a 30in pipe-lino for 160 chains to the bank of the Taieri! River, near to Mr Anderson's proposed power house, marked ' C,' with a total bead of 750 ft. The total length, of this route from intake to power house would be three miles 15 to 20 chains. The exact) length can only be ascertained by detail . surveys. The approximate cost pf carrying^ out this scheme should not exceed £28,000. Should the time at your disposal to construe); the latter scheme- be, limited, in making your choice that, and that alone, should prevent its being- adopted, as- its great advantages both as regards .permanency and -immunity from interruption arfli clearly in its favour. STORAGE RESERVOIRS. "In any of the schems now before you to ensure for all tho year round the 500* horse-power in Duneclin, the minimum which our instructions involved, during the driest of seasons, it becomes absolutely necessary that sites for storage reservoirs should be found to fall back upon in the event of the supply falling below the minimum, also in the probable event of a demand for an increased horse*power above the 500 quoted. That this probable necessity can be met is satisfactory. Mr Anderson in his report refers to two good sites for storage reservoirs, and a third one ifl to be seen at Mr Anderson's proposed intake, all of which may be erected to the average height of 40ft, to hold 40,000,008 cubic feet of water each, at a cost of from £3000 to £4000 each. The holding capa* city can be doubled when required. SUMMARY OF REPORT, i " Showing comparative length of systems i entailed in carrying: out each scheme ! relatively. "City Engineer's route: Seven miles 20 chains. Mr Anderson's 0.8. route (the best) : 18 miles 75 chains, which route (as shown by Mr R. S. Allan in his report dated 22/9/02) can. be shortened" ib eight' miles 59 chains. Messrs Browne and Stewart's alternative routes — Continuous pipe-line route : Six miles 40 chains ; tunnel and pipe scheme (approximately) : Three miles 20 chains. " We desire, in conclusion, to express our thanks to Mr R. S. Allan for bis courtesy and able assistance during our investigations, and also to congratulate your council upon having so valuable a source of power, capable of such extended developments atl your command. — We have the honour, etc.* " RIOHABD H\ BKOWNE. "R. T. Stewart." We understand the Tramways Committee' will recommend the council to adopt the . tunnel scheme, which it is estimated will take 15 months to complete. This, of course, will involve the use of a temporary} bteam plant.

Nearly 2000 more people travelled, by rail to "Flemington on the last Melbourne Cup day than to the event the previous year. The system of lighting by water gas, which, was to bo adopted by the Waimate Borough Council, has now fallen out of favour with, the councillors, and they have resolved to obtain the opinion of a soicitor on the question of the termination of the agreement with Mr Watt, wfio was soon to commence the erection of his gasworks.