GREY BOROUGH COUNCIL.

Greymouth Evening Star, Volume XXXI, 15 November 1901, Page 4

GREY BOROUGH COUNCIL.

The "regular meeting of the above Connell was held last night. Present — the Mayor, Crs M‘Lean, Thomas, Steer, Joyce, Petne, Sheedy. Prom National Bank agreeing to terms of overdraft.

Prom Mr 11. Coe refusing £2OO for land as inadequate. Air Petrie thought that i i dea ing with old people, and in taking away their homes from them, the Borough Council should deal liberally. Cr Sheedy held a like opinion, but thought that perhaps £IOO was too much. On the motion of Cr Thomas it was resolved that the Mayor, Crs Sheedy, Petrie, Joyce and Thomas be appointed a committee to sec what could be done towards coming to an amicable arrangement.—Carried. From District Engineer of Railway asking for a reduction of 10 per cent on all gas used by the Department. Referred to Gas Committee for report.

Prom Mr Greaney applying for a p -r/nit to erect a new forge in Mackay street. The Mayor moved that the Council cannot interfere with the authority of tiic Town Surveyor. Seconded by Cr M’Lean and carried, and further that t io law be inforccd against all boilers that are in the town in a condition contrary to the bye-laws. The Finance Committee reported accounts amounting to £IOBB 15s had been passed for payment. That the balances were as follows Dr Loan Account ... ••• £702 10 9 Dr D.strict Fund No 2. ... 2882 9 6 Cr District Fund No 1. ... 2027 6 G

The Public Works report recommended the formation of a footpath in Wharf Street in its turn.

Mr Napier-Bell’s report on the water supply scheme was read as follows “In the early part of June your Engineer sent me to Hobart his preliminary plans for the water supply of Greymouth, with instructions from yourself through the Town Clerk to report on the suitableness or otherwise of the plans and sufficiency of the estimate. I carefully inspected the plans which were merely outline sketches of the design and although the information was scanty it was sufficient to _ enable me tt report on them, which I did in a report dated 3rd of June.

Having returned to New Zeeland I have your instructions to come and personally inspect the locality chosen for the source of sapplyi and the site for the reservoir, which I have now done and beg to submit the following report on this subject. Before adopting the source of supply now under coosideration, your Engineer, Mr E I Lord, prospected the country all round, but found no satisfactory source except Coal Creek, 9£ miles from Greymouth in the Paparoa Binges. He estimates the cost to bring in this water at £25,000: it is not so good water as that off the main river, it would have to be filtered, and taking into consideration the difference of cost, the risks, maintenance, and unforseen items of expense which a detail survey would probably revea', I think the selection of the river itself as the source of water supply is fully justified.

Mr Lord estimates the cost of the pumping scheme at £12,204, and I estimate the yearly cost at £552, and adding £6lO for yearly interest brings the total up to £1162 a year; the estimated yearly cost of the gravitation scheme would be about £lslO, the difference is therefore £348 a year. I therefore consider that the selection of the Grey Eiver close to town as the source of supply is preferable to a gravitation supply from Coal Creek. The pumping involved is not a serious consideration, seeing that cheap coal is to bo had, and everything considered the pumping is preferable to the gravitation scheme. The Grey is so large a river compared with the population above Greymouth, which is likely to pollute it; it is so frequently subject to the cleansing influence of floods, and the water is so aerated in its Jong course to the sea, that on the score of possible pollution I have no fear that any difficulty can arise. London derives its supply from the small River Thames into which a dense population discharges its drainage above the city, and many towns in Europe derive their water supply from the adjacent river under similar conditions to this. The greater part of the value of a water supply in this case is as a protection against fire, and in such a rainy climate there is always abundance of the best of all water, that is the rain, if at any time objection should be taken to the river water for drinking purposes.

I would propose however to take further precaution to ensure the purity and to preserve the clearness of the water from the turbid condition in times cf flood, that the supply bo taken from as deep down under the shingle as possibe, and that precautions be taken to keep the collecting culvert which would lead into the pumping well at all times covered with a sufficient depth of shingle. This would make an excellent natural filter bed which could be relied oa at all times to act its purpose. The shingle beds of the Grey are apt at one time or another to be washed away by changes in the direction of the stream; but the shingle bank at present existing must be pre vented from being washed away, as it is important ta collect the supply underneath the shingle, a practice which is much approved in many sources of water supply in Europe, as it saves the expmse and trouble of fi’tsr beds, the water being sufficiently filtered by passing downward through the shingle to the collecting culvert. To protect the shingle bank from being swept away may possibly be found to be difficalt, but it can be done by partly surrounding the shingle bank from which the supply is to be drawn, with an embankment of rough stone strong enough to resist the floods, as I have shown on plans. In case the river should some day shift its cource by breaking through at the bend above the racecourse, there are two large creeks which must flow down the present course of the river as far as the proposed intake, for the pumping supply, and these will always yield abundance of water for the collecting culvert and pumping wells. I have therefore no fear that the contingency of the Grey River stuffing its course in future might lay dry the proposed intake for the pumps. On plans herewith I have drawn this collecting culvert, which should be made of best heart of silver pine. The bottom of the box is open and it should stand on a clean bed of shingle, and the trench in which it is should be filled to the surface with shingle. At the depth shown the collecting culvert should be extended out across the bank as far as necessary to give the required supply, and must bo protected from being disturbed or washed out by floods, by the rough bank of stone mentioned above-

In designing works of water supply it is important to decide what future increase of population is to be anticipated, and wbat daily quantity is to be given per head. The present population being 4300 if we assume that there will be 12,000 in the future, ! think that would be a reasonable provision, and 40 gallons a day allowed by Mr Lord is a very good supply, sufficient for al'lpuiposes. This supply is equal to 340 gallons a minute, to which I add water for five fire jots, which brings uo the total required water provided for emergency to 965 gallons a minute, and the pipes being allowed a head of 70 feet at all times when full water is going on, leaves the effective head ns 182 feet, requires on eight inch main pipe

to supply 12,000 people at the rate of 40 gallons daily per head, together with the supply of five fire jets. By partly shutting off the town supply during a fire, more than five jets would be available. The reservoir is designed to hold 121,000 cubic feet, or about 800.000 eallo is, which i- ■ pi' ! to ■r: dy .v« -y •' supply for the pr sen:. (m, ulau o 1 4.300 and nearly two days’ supply for 12,0u0 people. 1 have carefully examined the site for the reservoir, which is a narrow spur of the limestone hill. I consider the site an excellent and most convenient position, the material being a capping of clay on top oflimestone,' in which I have suggested to Mr Lord that the reservoir be sunk 6 feet deeper than it was shown on the original plans, as it is safer to sink down than to build up, and the plans herewith show this 6 feet extra depth. The bottom of the reservoir is 268 feet 10 inches above the datum, which is the zero of the vide guage. The bottom and walls arc io be of concrete, and I have omitted the puddle originally shown as it serves no good purpose. The concrete being a good mixture, properly made and deposited, and covered with cement plaster $ inch thich will make the walls and floor water tight.

By holes sunk to test the ground it is seen that there is water at the level of the proposed bottom of the reservoir. This possibly comes from the limestone rubble which underlies the surface clay, but it can easily be cut off by laying a drain at the level of the bottom right across the spur outside the top end of the reservoir.

The walls of the reservoir are sloped £ to 1 and are almost entirely in cutting, only in a few places do they stand a few feet above the ground. Tbe valves are placed in a small tunnel or culvert over which is placed the valve house. The reservoir can be laid dry and washed out by means of a 4 inch syphoned pipe with a valve, and I have advised Mr Lord to omit a partition wall in the reservoir, as whenever the reservoir is to be washed out the pumps can pump water direct to town, the valve for the purpose being in the culvert mentioned above, and worked from the valve house.

The limestone on the top of the spur would make good concrete, and there can be no objection to using it if it is quite clean. I should, however, expect that in breaking it up there would be produced much chalky dust which would be prejudicial to good concrete, and as there is no water up there to wash the broken stone it may be safer to use good clean river shingle and good sea sand for the concrete plastering : and it is needless to reiterate that every care must he taken to make good sound and water .tight concrete.

‘To pump 500 gallons a minute or 30,000 an hour into the reservoir an extreme height of 300 feet requires an engine of 80 horse power. For some years to come one 45 horse power engine could do the required work, and subsequently adding another 45 horse power engine would do the work for the anticipated greater population. But this may not be the best combination, even ignoring the evident risk of having only one engine ; it is advisable to leave the disposal of the engine power to the makers, who will give the bast advice provided they are supplied with all necessary information and data.

I have studied the town reticulation as laid out by Mr Lord, and with a few corrections suggested it will be all right. Uhe water pipes in the streets should be laid as far from the sewer pipes as will not cause them to be disturbed it the sewer trenches are opened, and also a depth of two feet six inches below the surface is quite sufficient for the water pipes.

It will not be necessary to use flange pipes on the reservoir hill, but it would be advisable to have about three stops to prevent the pipjs dragging, which stops are easily made of a block of about one cubic yard of concrete made round the pipe. The pipes then cannot slip the concrete, and the concrete buried in the earth prevents the pipes dragging, if they would have such a tendency. Ail the pipes should be tested before being laid. For the control of fires it is important that certain parts of the reticulation can be closed, which requires that valves in the pipes be properly placed, and I have discussed this subject with Mr Lord.

Mr Lord’s estimate for this work is £12,250 in which the prices for the pipes are about right, but I think that for the engines and pumps will be found too low. Such estimates are, however, very uncertain, for the prices vary greatly according •o the kind of engines and pumps that are used; but makers are very ready to give estimates, and from them a reliable idea of the cost can be obtained. The cost of pumping well, collecting culvert, engine house, reclaimed land for its foundation, stone bank to protect shingle bank, can easily be fixed by Mr Lord. The laying of the collecting culvert and the pumping well involves tide work, and the liability for interruption by floods. It is all important that this work bo well and carefully done, and whatever the difficulties met with that the culvert and well be laid at the depth shown. It would therefore be advisable to do this part by daywork, although all the rest be done by contract.

Taking Mr Lord’s estimate of the total of the alternative schemes by gravitation and pumping, I give herewith my estimate for the yearly cost of each : Gravitation scheme estimated

by Mr Lord £25,000 Pumping scheme estimated by Mr Lord 12,204 Difference in favour of pump-

ing ... - 12,790 Yearly cost of Gravitation scheme, attendant at head work with house 156 Damage ans. repairs very un-

certain, say 104 Interest 5 per cent on £23,000 1,250 Yearly cost 1,510 Pumping scheme Engineer and house 150 Fireman and valve attendant

313 days at 8/- 125 Coal three pounds per horse power per hour on 80 h.p. for 320 days; 210 tons at 15/- 157 Ordinary repairs, say 50 Oil waste, stores, etc 64 Interest at 5 per cent on £1,204 610 Yearly cost 1,162 Difference of yearly cost in favor of pumping 348

The saving of a puming scheme over gravitation is thus seen to be about £1 a day, and I believe in every other respect, such as safety from accidents, freedom from necessity of filtering, and greater convenience, the pumping scheme of Mr Lord will be found to be equally satisfactory. A long discussion ensued and the report was adopted. Cr Thomas then moved that tenders be called for the work as speedily as possible. A long discussion ensued as to the manner of work, and it was decided to let the reservoir in one contract and the pipe laying in another. Cr Petrie desired it to bo inserted as a special clause that for ordinary work residents should have preference. Or Steer was of a like opinion, but other councillors held that in such matters they must give the contractors a free hand.

The Town Surveyors report showing how Boundary street on the western side had been dealt \vith was read and adopted.

In regard to Chinese burial ground the Town Clerk reperted as follows “The only suitable place for a Chinese burial ground outside of our own Cemetery Reserve, and with the Borough, is on part of Municipal Reserve No 197—now remed to Di Ming and used as a Chinese ga>-d ii - th • I'- .- fur wtiich <-xp r . on Ist Ja ma y n x r . A railway cro sing has been left at tbe place, rendering it easy of access. The Chinese have groat objections to the plot set apart for them in our own Cemetery, owing to the soil being a wet retentive clay. Cr Joyce brought up the condition of Willis street, but the Town Clerk informed him that work had already been commenced.