TAIHAPE BOROUGH COUNCIL

Taihape Daily Times, Volume XI, Issue 3494, 24 May 1920, Page 6

TAIHAPE BOROUGH COUNCIL

REPORT ON GRAVITATION * WATER SUPPLY. , The following report on Taihape’s gravitation water supply was laid on the Council table on Friday night: In accordance with instructions I herewith, report on Gravitation Water Supply for your Borough. Careful levels have been taken and a suitable pipe line has been found for a gravitation pipe line from the Hautapu river to the existing high level reservoir.

In my preliminary report I _ was taken to a point on the river which, after the recent full investigations, proves to be ‘less suitable than the one now proposed. By tapping the river at the point now chosen a pipe line almost direct in its course can be laid. It is true that this pipe line is over several high points, but these are all below the hydraulic gradient between the intake and the reservoir, and therefore do not effect the quantity of water which may be de‘lYvel-‘ec'l. ’ In «order to be as nearly accurate} as possible in‘ my estimate, the pifie line was thoroughly investigated, and permanent pegs were ,driv‘e‘n"”excepting for the first two miles which isfairly obvious country. A longitudinal section has been prepared on a considerably distorted scale in order to get it on to ‘one sheet andto the lay-mind this may be confusing. - I In order that the Council may ap-) precfate the true nature of the country ‘ traversed I have made a small dia- ’ gram to nafiiral scale oei:-ne of the’ peaks shown‘ on the longitudinal sec- 1 tion. ; 1

,The total head available at the existing reservoir is 181 feet and the pipe line is 538 chains in length. If an éfght inch pipe is adopted the amount of Water fieiivereé“ ‘Will be 489,000 gallon‘s'_p?er day. .With a. nffie inch pipe“ffie amofint Jeliferea ‘will be 648.000 galloni. ’

INTAKE. As the fall of the river at the site of the proposed intake is favourable it is proposed to use a simple box intake. The box will be buried below the bed level and will be filled with stones to act as a strainer and also to give it weight. The intake will be connected to a pump by a suitable pipe and a scour valve 'will be’ai provided. This avoids the expense of a clam and also the bad conditions set iup by damming the water. Detritus in the form of ifrooci, leaves, sawdust, etc., will not be collected in large Quantities and there will be no accumulation of silt such as would be found with a dam.

PIPES. Your Council I am afraid has little choice with regard to the kind of pipes. Cast iron pipes which are undoubtedly the best, are quite out of the question owing to the price and the cost of laying and there is nothing available but steel pipes.

Steel pipes can be procured in New Zealand or can be imported. In my estimate I have’”'alloWecl for Spiral Steel Pipes manufactured in Wanganui. The price has increased considerably during the last few months in synmathy with the steel market, lahour. and exchange and may increase further before your Council is ready

to place an orfier.

ESTIMATE OF GRAVITATION MAIN, ETC.

In the following Estimates 1 have -allowed for the difliculty that will be met. in laying :ouf"ET.e 13ip‘e‘s.‘ The pipe line in 501119 pal~ts‘is out of reach of e.:;.3' t'orme(! road and the pipes will have to ‘me Sledged into place.

EIGHT INCH PIPE LINE. £ 538 chains Sin spiral pipe, at 8/ per foot . . . . . 1-1203 Trenching - , at 5/ per yard ... 3000 Specials in pipe line .. .. 000 Cartage, handling, and joiningpipes . . . . .. 1270 Intake ' 400 Valve at reservoir .. .. 20 Special bends for pipe .. 250 Tressling across ' rivers and gullies 600

£20,343

‘ Allow £20,500. INCH PIPE LINE. : . The additional cost of a nine inch pipe line will be £2500} Allow £23,000. .

REPORT ON EXTENSION OF V'y'N[‘Eß RETICULATION.

A plan of ;the required ex't7ens_ions 130 your water reticulation has been pneparcd. On the fvestern side of the ?I‘ailW9-y this reticulation is separated from the existing mains because of the excessive pressure which would result on the lowest levels. "The greatesf ‘static pressure on the exfensions West

‘of the I'ailw:~.y line will be lsoibs per square inch, and this will occur at the foot of the Hospital steps. Biafiaroa ‘Road is to be connected with the existing nine in. main, and" the new main will be extended into Goldfinch Street. About. 15 chains down Goldfinch Street from Mataroa §Road a pressure reducing valve would be necessary, if u dcad~end is to be a{'oided. For ".hC present. I think -a

dead end could be allowed, as shown on the plan. ’ , With a. 4111 main aloiig Mat-.u'oa Road there will be maintained 3. pressure of 1001bs per square inch, with 160 gallons per minute draw off, and this should be suitable for two hoses with three-quarter inch nozzles, so that a dead end will not greatly afiect fire fighting '

ESTIMATE FOR EXTENSION OF WATER RETICULATION. £ » d 175 chains Gin. spiral steel pipes at 5/9 per foot .. 3020 3 2 0 170 chains 4in spiral steel pipes at 3/ per foot .. 1742 8 0 5200 chains trenchings ' (Ift Oin and Aft) at 5/ per cubic yard .. .. 1300 0 0 40 bends crosses tees, at £4 each .. .. .. 160 0 0 S Oft sluice valves, complete, at £ls each . . 120 0 0 0 4in sluice valves, complete, at £lO 10/ each. .. 03 0 0 90 fire hydrants, at £6 each 540 0 0 200 house connections, at £3 10/ 700 0 0 Cartage in town .. ~ 150 0 0

. £7790 0 G Allow £BOOO. REPORT ON EXTENSION OF SEWERAGE. Considerable difficulty exists in adequately sewering the portion of the borough on rhe west side of the railway not yet served. It is rarely possible to connect houses on both sides of any road to a central sewer, and provision has to be made to drain houses down-hill by a sewer on the back line of proper-ties. Six-inch, sewers are ample in all cases, but owing to the difficult nature of the country, an excessive number of manholes are required. It is essential that a man-hole shall be placed at every angle of a sewer, both vertical and horizontal, in order to have full command of any length should blockage occur.

At present I have not provided for-' scwcring-Wren Street, as there is no natural fall, except into who Otaihapc stream. I suggest that any houses not within reach of the proposed sewer on Kaku. 1‘i';)€l(1 should have private septic tank.» The alternative is to pump the >'c\\'ol'agc fronl.'i-his quarter into K:=.l\::1 I-lon-Cl. at 3, coneicleiuble cost in initial 0:-:penditurc and up-keep. The cost of a small pumping station will be in the region of £3OO to £IOOO including electric motor, pump, electric lines, receiving tank, and rising main, and this may be considered out of proportion to the service i-end~ ered.

Small septic tanks for the few houses concerned running in to the Otaihape stream will not cause any appreciable nuisance. Owing to some doubt concerning the levels of the existing system, I have not made definite proposals for the connection of the extension to it This however is a matter of detail that can he attended at a later date. A sum of £SOO has he~eh allowed to cover this work. EXISTING SEPTIC TANKS. Your existing septic tanks require clearing out before the extensions

can be connected. This will be a costly job for which I am allowing £SOO, but no definite estimate is possible, and any excess should in my opinion be paid as for maintenance. When the tanks are restored to their normal "capacity the extensions may be added, but the "Council will have to look forward to a day when filtration will be required in order to keep the stream reasonably sweet. For the present however, cleaning out the tanks will give reasonable treatment for the population connected.

ESTIMATE OF SEWERAGE EXTENSION. The following estimate is based on current prices of glazed pipes. £. 6in Sewer Pipes only 470 chains £5 2350 Man-holes 73 each £2O .... 1460 Lamp Ploles 10 each £7 .... 70 Y Connections 940 each 3/ .. 141 Excavations (2’ 0” wide) 13600 cubic yards 6/ 4080 6i’ Sewer laying 470 chains 14/ 329 Jointing Cement 200 hags 8/ 80 Sand 20 cubic yards £2 40 Second cartages 225 tons £1 22 > House Connections 200 each £8 1600 Clearing out septic tanks lump sum 500 Connection with existing system lump sum 500 £11,375 Allow £11,500. RESTORATION OF ROADS. i

It is to be noted that no provision has been made in any of the foregoing Estimates for restoring road surfaces where sexvors and mzfius are ‘laid. I cannot .estiln-ate the amount

degreo of cer-

required with any minty, as in many cases sewers or mains will be laid in the un'ln~ef.alled portions of roads. A sum of £SOO should enable road surfaces to be re's"f‘orcd to a reasonable <:.o.udition to allow the usual In'allll'ellancc to pick up the Work at a later dzrto.

TOTAL OF ESTIMATES. Gravitation Main Sin dia. .. £20,500 Extension of water reticulation • • • • 8,000 Extension of Sewerage .. 11,500 Restoration of roads • • 500 Usual allowances, 10 per cent. • • • • 4,000 Extra contingency .. .. 1,500 First year’s interest on loan, etc., 0 per cent. .. . • 2,800

£348,800 A loan of £50,000 should be raised over HlO \\;ho]o of these works. If a Qin. gl'a\*itil”fion main is adopfed instead of Sin. as allowed for, add £2500. ' TI-IE I’l;.»\;\‘S.

Tlic plans accompanying' tins report are for the purposes of estimating. The best care lias been taken with levels, etc., but revision, amendments and adjustments will be necessary before the work can be carried our_ Yours faithfully, H. F. TOGO GOD, C.E., No 11, Grey Street, Wellington, 10th May, 1920.