WATER-CONSERVATION (FURTHER REPORTS ON) FOR MINING, IRRIGATION, DOMESTIC, FIRE-EXTINCTION, AND OTHER PURPOSES.

Appendix to the Journals of the House of Representatives, 1898 Session I, C-04a

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1898. NEW ZEALAND.

WATER-CONSERVATION (FURTHER REPORTS ON) FOR MINING, IRRIGATION, DOMESTIC, FIRE-EXTINCTION, AND OTHER PURPOSES.

Presented to both Houses of the General Assembly by Command of His Excellency.

Mining Township op Waihi. Domestic Water-supply. I now submit my report, together with a sketch-plan of the above township, showing the position of the proposed headworks and pipe-track, with aneroid levels in red ; also a sketch of proposed reservoir, and details illustrating scheme recommended. It may be as well to preface recommendations for a supply of water, both for domestic and fireextinction purposes, by a brief description of the locality and the somewhat peculiar conditions under which a scheme for a general water-supply must of necessity be formulated. On paper the town is represented as occupying a space of about two square miles, or 1,280 acres. In addition to the business part, which is in Waihi Street, there are numerous dwellings scattered over a large portion of the above area, for the most part on 1-acre sections, and in the vicinity of the batteries and gold-workings, which in the course of events have formed detached outlying centres of population Being so widely separated from the main centre of reticulation or distribution (which is round and about the corner of Waihi Street and Rosemont Road), to convey water to these outlying tenements for fire-extinction would be almost prohibitive, except at an unwarrantable expense. Pure water for domestic purposes only, as at the other townships already reported on, is an urgent and vital necessity for the preservation of health at Waihi, especially among the infantile population, and is here provided for in the scheme I am about to describe, and in the general Recognising the importance of a pure water-supply, several proposals have from time to time been made to obtain even a temporary supply pending the raising of sufficient funds to carry out a comprehensive permanent scheme; but Waihi, like the townships previously dealt with, is in the unfortunate position, owing to the tenure under which the land is held for business and residential purposes, that the people are debarred from raising loans under the Local Bodies Loans Act. For purposes of this report I examined :— ~ . . (1) The head-waters of the Waitete Stream, but found the water, although permanent, m such small quantity at a sufficient elevation that to obtain any useful pressure this source was not worth 611 61 (2 a ) A scheme to convey water from the Waihi Company's race at a point overlooking the chief centre of population, combined with standpipes at convenient points, would no doubt be sufficient for the business part of the town, provided the purity of the water could be assured, and answer the purpose for domestic consumption, but would be of little use for fire-extmction. (3 ) A proposal to tap the Waihi Company's high-pressure main with a 3 in. pipe, and bring water into the town and erect standpipes. This could only be considered of a temporary nature, and again, would practically be of little use for fire-extinction purposes. '(4 ) A scheme to take water from the condenser of the Waihi Company s pumpmg-station (which it was stated would supply 125 gallons per minute), and also create one or more small storage-reservoirs with filtration-beds. By this means a comparatively pure supply could be laid on but, as only a comparatively low head could be obtained, it, again, would be of little use for the suppression of fires. „,.•,, ■ -, -, ,• >i • The quality of water from any or, in fact, all of these sources is rendered highly impure, not only by contact with the surface drainage from contiguous huts and other insanitary habitations on the upper bank of the open race, but also through animal contamination. Any of these schemes can under the circumstances, only be regarded as objectionable and temporary expedients. ' After fully considering the different proposals I am of opinion there is no other source from which to obtain a permanent and fairly pure supply of water equal to the Mangatoetoe Stream, which was I understand, originally reserved for the purpose, and therefore a site for the intake and head-works has been selected about a mile and a half from the corner of Waihi Street and

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Rosemont Road, which is about the centre of the business part of the town. The site is at the termination of the Waihi Company's firewood tramway, which nearly follows the stream up from the pumping-station on the round hill to the north-west side of the town, and although it is a favourable site, in so far as it has a good rock foundation for a weir or dam, and holding-capacity for a filter bed, the water is not at present free from impurity and surface - drainage contamination, but it can be made pure by cleansing the creek-bed and filtration. So great has been the consumption of firewood for use at the battery-kilns that the catchment area is almost denuded of timber; consequently no difficulty should arise in coming to an equitable arrangement for the removal of a temporary stable and woodcutters' huts on the hill above. The clearing-out of log culvert, broken slabs and decayed timber, and debris blocking the creek at the proposed site of reservoir will also be necessary. On goldfield townships, subject to rapid and intermittent fluctuations of prosperity and depression, the populations are generally in a floating condition, but in the case of Waihi the steady and magnificent gold returns from the premier mine warrant anticipation of permanent prosperity for a number of years. From information I have been able to gather the present population may be estimated at somewhere about six hundred to seven hundred, excluding the outlying clusters of tenements before mentioned. As there is a reasonable probability of a considerable increase of population as the mining industry develops, and consequent expansion of the town, it will be advisable to provide for about double the present number, say, fifteen hundred, and upon this figure the scheme and estimate of approximate cost is based. The Mangatoetoe Stream, at the point of intake, runs at an average (eliminating floods) of about two-thirds of a Government sluice-head, or 359,424 gallons per day of twenty-four hours. This for a population of 1,500 equals 239 gallons per head per day—a most liberal allowance even for four times the population, and ample for all requirements without any provision for storage. The creek, however, is so confined in a narrow and deep rocky gully that to trap the water it is necessary to, at any rate, construct a comparatively high concrete dam. When the creek-bed is thoroughly cleared out a fair-sized reservoir will thus be created, estimated to contain about 300,000 gallons. Making the usual allowance of 30 gallons per head for a population of 1,500, this will provide a supply for 17 days, which will be available in cases of emergency. The proposed head-works consist of a concrete dam (with a rough filter-bed at the back), to be built in the solid rock ; a waste weir on the side 16 ft. in width, the sill being 14 ft. above the creek-bed, with a silt-pit in front; and two iron gratings, crossing the creek and its northern branch, to prevent floating snags and rubbish from entering the reservoir. The supply-main from the silt-pit of 6 in. cast-iron pipes will follow down the right bank of the creek, and crossing it in two places on light trestle bridges, in positions as may hereafter be determined as most convenient, to the new valley road as shown on the sketchplan, thence down the road past the schoolhouse as far as the Waihi Street and Rosemont Road corner. From that point 4 in. pipes will distribute the water about half-way to the bridge on the Karangahake main road to the corner of the block, past the post-office on the Rosemont Road, and up Waihi Street as far as the junction with Gilmour Street. This length of mains, provided with scour-valves, stop-valves, and fire-plugs at suitable distances, is intended to serve the business part of the town with a domestic supply and a means of extinguishing fires. At the Waihi Street and Rosemont Road corner a head of about 140 ft., and at Gilmour Street 120 ft., will be available, the reservoir being at an elevation of 150 ft. above O at bottom of Waihi Street. Beyond the Gilmour Street corner, and following the Barry Road to about the Martha battery, and from the bottom of Waihi Street to near the Waihi-Silverton battery, with occasional branches along either line where required, 1-J-in. galvanised-iron pipes are proposed to be laid for a domestic supply, but not for fire purposes. Laying the water to the houses is not considered in this extension scheme, as I conclude standpipes at convenient distances and localities would best answer the requirements of the scattered houses. On the expansion of the town these 1-J-in. pipes can be replaced by 4 in. mains and fire-plugs, &c. Maintenance will cost little, it being only necessary to clear the grids occasionally and scour the bottom of the silt-pit and the mains frequently. The reservoir should be securely fenced from cattle for a distance of at least 2 chains on each side of the creek, and from the dam upstream for 10 chains, and all decayed vegetable matter removed, so as to preserve, as far as possible, the purity of the water. In the event of this scheme being carried out when permanent levels, &c, are fixed, it may be found capable of some modifications; but in any case I recommend, if the extension scheme for supplying the suburbs is not undertaken, the laying of the pipes to the extent indicated on the plan for domestic fire purposes. Approximate estimate for whole, £2,725. 26th October, 1898. T. Perham.

No. 2. Township op Te Aroha. Domestic Water-supply and Electric Lighting for Domain and Town. In accordance with telegraphic instructions " to visit Te Aroha and report on question of watersupply for domestic purposes, the water first being used as motive-power for electric lighting both town and domain," I now forward the result of my examination with preliminary recommendations, and two sketch-plans illustrating the scheme. Communicating with Mr. T. Gavin, Chairman of the Domain Board, I found that the Tutumangeo Stream, generally known as " Lipsey's " Creek, was the source of supply in favour, on account of its convenient situation and purity of the water, but at the same time doubts were freely expressed as to its volume being sufficient for motive-power or even domestic purposes, except in