FURTHER PAPERS RELATING TO THE CONSTRUCTION OF RAILWAYS. (NORTH ISLAND.)

Appendix to the Journals of the House of Representatives, 1871 Session I, D-06g

D.—No. Go.

FURTHER PAPERS RELATING TO THE CONSTRUCTION OF RAILWAYS. (NORTH ISLAND.)

VIII.-EEPORTB AND ESTIMATES ACCOMPANYING PARLIAMENTARY SURVEYS.

I. —AA rELLINGTON TO NAPIER. II. —Auckland to Newmarket.

PRESENTED TO BOTH HOUSES OF THE GENERAL ASSEMBLY, BY COMMAND OE HIS EXCELLENCY.

SCHEDULE OF CONTENTS.

o. Date. Subject. 1 3 12th August, 1871 15th August, 1871 22nd August, 1871 ... Report and estimate of proposed Line of Railway—Wellington to Masterton. ... Report and estimate —Waikato Railway, three alternatire linet between Auckland Wharf and Newmarket. ... Memorandum on ditto.

D.—No. 60.

AVELLINGTON TO NAPIER RAILAVAY.—WELLINGTON TO MASTERTON. No. 1. Mr. Rochfort to the Hon. W. Gisborne. Sir,— Wellington, 12th August, 1871. I have the honor to send herewith plans, sections, report, and estimate of that portion of the Wellington and Napier Line of Railway between Wellington and Masterton. As might be expected, the cost of this line, with a mountain 1,330 feet high above the sea level to surmount, and four large rivers to bridge, somewhat exceeds the ordinary average of New Zealand railways. I estimate a line of 3 ft. 6 in. gauge, with stations and sidings, can be made and equipped for about £4,857 per mile. From AVellington to Petoni the line will skirt the road on the seaside; and, on inspecting the plans, you will see that the curves are so fitted to the road that a minimum amount of embankment is attained. This can be made cheaply, by throwing down the rock cliffs in mass, which then will have to be carried only a short distance; at the same time the road will be widened. From Petoni to the crossing-place of the Hutt River near Silver Stream, the line is forced near the river, and causes rather heavy cutting. The place known as the Gorge is passed on this side without any difficulty. The crossing of the Hutt River is good. The bridge starts from tho hill itself, and crosses the part of the river liable to floating timber with seven 66 feet spans; the part beyond, being shallow-flooded ground, is crossed with 538 feet of low bridging of a cheaper character, having spans only 16^ feet. Beyond this again, in a low place, 132 feet of low bridging is allowed to act as a safeguard to the embankment in the event of unusually heavy floods. From the Silver Stream the line follows along one side of the trunk road until reaching a point where the hill abuts on the road, about one mile nearer town than Cruickshank's saw-mill. All along this portion, ballast can be procured at a low cost. The line now contours up the hill which divides the fiutt from the Mungaroa Valley, reaching the latter by a cutting through the crown of the hill behind Mr. Cruickshank's. This portion is full of curves, the sharpest being 200 feet radius. A gradient of lin 43, about a mile and a half long, brings us to the top, when the line runs over level forest for two miles straight. The soil is very stony, and will itself supply sufficient ballast when the ditches are thrown up. To the top of the Mungaroa Hill, which is crossed about 100 feet below the level of the present road, the curves are numerous, and the grades vary from lin4oto 1 in 41. The line now runs level for four miles, as far as the Pakuratahi. The hill slopes are light, and average about an angle of 20° with the horizon. We now commence the ascent in earnest —two miles of 1 in 49, and three of varying grades from 1 in 40 to 1 in 46, bring us to the main saddle, and here we get a rest of 15 chains of level. The saddle is 1,379 feet above the sea level, and 1,232 feet above Featherston by spirit level, which agrees very closely with height ascertained by aneroid observation on my preliminary survey, the difference being only a few feet. This shows how these instruments may be relied on in preparatory surveys. The side slopes average about 30° with the horizon ; there is not much rock out-cropping, but we may expect to find it a few feet below the surface whenever the inclination of the hills is over 35°. I have based my calculations on this assumption, and have reckoned on turning the rock to account in building up retaining walls to lessen the contents of the embankments. On the AVairarapa side of the range, the hill slopes are steeper, and several long viaducts over deep gullies will have to be made, otherwise the character of the line is similar—grades, nine miles, 1 in 41, and one mile and a half, 1 in 54, to the plains of the Wairarapa. There the country is easy, the only expensive works being the bridges. The line passes through Featherston along the side of Johnston Street, passing the large Government reserve on which the old Land Office stands. This reserve would be useful for station purposes. The crossing of the Tauherinikau was chosen directly behind Mr. Bunny's house, that being the most favourable spot outside the Gorges. The actual bridge has only three 66-feet spans, but low bridging of 330 feet is allowed to carry off flood waters. Ballast is plentiful all through the valley ; the plain intervening between the last river and the AVaiohine is nearly all covered with stones. The Waiohine is crossed between Cotter's and Revans' saw-mills, with a bridge having twelve 60-feet spans and one 52, besides 198 feet of low bridging, which is distributed over the flooded ground. This crossing was chosen partly because it was the narrowest between Greytown and the Gorge, and partly to avoid a large swamp which lies between the railway line and the road. The line now crosses the Matai-Rawa Plain, which is also very stony, and then goes through the bush known as " Three-Mile Bush." This bush is really about five miles through, and free from swamps along the line, and uniformly level; several clearings are passed through by the railway. Totara can be got in quantity in several places in this bush. On emerging on the Taratahi Plain, a swamp 18 chains over has to be crossed; then another stony plain to the Waingawa River, which is crossed one mile and a half west of the coach road with thirteen 66-feet spans and two short pieces of low bridging of 99 feet and 66 feet for flood opening. This crossing was chosen because it is the narrowest, and as offering a good site for a bridge, also as being the shortest line to the Gorge. The line will pass about two and a half miles to the west of Masterton, but the intervening country is open and level. I will now compare the line of railway just described—as to length, cost, &c.—with one in which the Rimutaka Range would be pierced with a tunnel, with the view of shortening the distance. At an early stage of my survey, I was called upon to report on the probable cost and length of a tunnel line, and accordingly did so, but with information at that time necessarily imperfect. Part of this I am now able to supply correctly, and the rest may be gathered, although not in full, from a published Report on a Tunnel Line by C. O'Neill, Esq.

FURTHER PAPERS RELATING TO CONSTRUCTION OF RAILWAYS.

J>r—JSo. 60.

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FURTHER PAPERS RELATING TO

I will take, as common to both lines, two points —the first where the two lines would cross each other about one mile and a half south of the Pakuratahi Hotel, which by the railway line is twentyseven miles forty-eight chains from Wellington ; the second at the Telegraph Station at Featherston, which is just a quarter of a mile beyond Abbott's Hotel. The distance between these two points by the line over the Rimutaka being exactly twenty-one miles fifty-three chains; by the Tunnel Line the distance will be thirteen and a quarter miles, made up as follows, viz., nine and a half miles by the main creeks between Pakuratahi Hotel and Abbott's Hotel, Featherston (see Mr. O'Neill's report), to which must be added the one mile and a half and quarter-mile just described, to the points common to both, as well as at least two miles for contouring the lateral valleys and points of hills between the ends of the tunnel and the points in question. This allowance, it will be seen, is not too much, as the length of the coach road exceeds the length of the line by the creeks by more than two miles, at a much steeper gradient than the railway just surveyed. The comparative cost of the two lines may therefore be shown as follows. I havo already stated that the average cost per mile for tho whole length of line is £4,850 per mile; but, to make tho comparison fair, the estimated cost of that portion of the line now under consideration should alone be considered, and that amounts, without allowing for rolling stock, to £6,322 per mile. AVe have, therefore, assuming Mr. O'Neill's estimate for the tunnel to be correct —tunnel line 13 j miles —viz.: Tunnel, If mile, at £660 per chain ... ... ... ... £85,800 11| miles of railway, at. £6,322 ... ... ... ... 73,496 £159,296 Rimutaka Line —21 miles 53 chains of railway, at £6,322 ... 136,954 Showing a saving in cost by the Rimutaka Line of ... ... £22,342 And a saving in distance by the Tunnel Lino of 8 miles 33 chains. I need not explain that the time expended in making the Tunnel Line would be much longer than needed for the other —probably three times as much, or in the proportion of five or six years to two years. I have not yet completed the second section of the line, viz., from Masterton to the Manawatu Gorge, but hope to be able to furnish plans, report, &c, in about a month. The first section terminates about a quarter of a mile on this side the AVaipoua, a distance of 70 miles 5 chains from AVellington. I have, &c, John Rocufort.

Enclosure in No. 1. Approximate Estimate —Wellington .and Napier Eailway. From Wellington to Mastertou —length, 70 miles 5 chains; single line of railway, 3 feet 6 inch gauge ; with 40 lb. rails. £ s. d. Bush Clearing—33 miles 16 chains, 2 chains wide, at 10s. per chain ... ... 1,328 0 0 Earthwork — Main Line, 828,857 cub. yards, at Is. per cub. yard ... ... ... 41,442 0 0 Mixed earth and loose rock, 199,323 cub. yards, at Is. Gd. per cub. yard ... 14,949 4 6 Eock cutting, 107,144 cub. yards, at 4s. Gd. per cub. yard ... ... ... 24,107 8 0 Stations, Sidings and Deviations, and Approaches, 01,248 cub. yards, at Is. per cub. yard ... ... ... ... ... ... ... 3,062 8 0 Eetaining Walls, 45,680 cub. yards, at 12s. per cub. yard ... ... ... 27,408 0 0 Bridges and Viaducts—2,826 feet, at £4 per foot ... .., ... ... 11,304 0 0 „ 259 feet, at £5 per foot ... ... ... ... 1,295 0 0 3,900 feet, at £6 per foot ... ... ... ... 23,400 0 0 „ 2.G88 feet, at £10 per foot ... ... ... ... 26,880 0 O Culverts—one hundred and fifty-nine, 1 foot, at £6 10s. each ... ... ... 1,033 10 0 „ sixteen, 1 foot 6 inches, at £13 each ... ... ... ... 208 0 0 „ fifty-eight, 2 feet, at £16 each ... ... ... ... ... 928 0 0 „ nine, 3 feet, at £32 each ... ... ... ... ... ... 228 0 0 „ eighteen, 4 feet, at £36 each ... ... ... ... ... 648 0 O „ nine, 6 feet, at £48 each ... ... ... ... ... ... 432 0 0 Permanent Way — Eails and Fittings, 69 tons, at £10 10s. per ton ... £72110 0 Sleepers, 2,050, at 3s. each ... ... ... 307 10 0 Ballast, at 2s. per yard... ... ... ... 176 0 0 Laying ... ... ... ... ... 88 0 0 70 miles 5 chains, at ... £1,293 0 0 per mile 90,526 3 3 Stations and Sidings, say 3 miles at £1,293 per mile ... ... ... 3, 879 0 0 Level Crossings, say ... ... ... ... ... ... ... 500 0 0 Turntables, four, at £110 each ... ... ... ... ... ... 440 0 0 Points, Switches, and Crossings, twenty sets, at £15 each ... ... ... 300 0 0 Goods Cranes (U ton), six at £30 ... ... ... ... ... ... 180 0 0 Signals, eight, at £25 ... ... ... ... ... ... ... 200 0 0 Station Platforms and Sheds, say six, at £250 each "... ... ... ... 1,500 0 0 Water Tanks, say ... ... ... ... ... ... ... ... 200 0 0 Fencing, 77 miles 20 chains, at 20s. ... ... ... ... ... ... 6,180 0 0

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D.—No. Go.

Rolling Stock— £ s. d. Locomotives, four, at £1,600 ... ... ... ... ... ... 6,400 0 0 Passenger Carriages, six, at £300 ... ... ... ... ... 1,800 0 0 Goods Waggons, forty, at £80 ..•: ... ... ... ... ... 3,200 0 0 Covered ditto, six, at £105 ... ... ... ... ... ... 630 0 0 Mineral ditto, six, at £80 ... ... ... ... ... ... 480 0 0 Break Vans, four, at £230 ... ... ... ... ... ... 920 0 0 Engineering expenses, 5 per cent. ... ... ... ... ... ... 14,779 13 6 Contingencies, 10 per cent. ... ... ... ... ... ... ... 29,559 7 0 Total ... ... ... ... ... ... £340,327 14 3 John Rochfort.

WAIKATO RAILAVAY—ALTERNATIVE LINES AUCKLAND WHARF TO NEWMARKET. No. 2. Mr. Wrigg to Mr. Blackett. Sir, — Auckland, 15th August, 1871. I have the honor to transmit tracings of the plan and sections of the three alternate lines as surveyed from Newmarket to Auckland, with an approximate and relative cost of each. I have attached to the estimates such notes as appeared to me desirable for your information, and have only to add that the quantities have been taken out at the slopes noted on the section, and as if the ground in cross section was level. I am of opinion that the two small tunnels on the Coast Lino will be safe with timber lining, and that they could be executed at the price per yard I havo named, the material being beds of sandstone and indurated sand in horizontal layers, so that it is not probable that water will interfere with their construction. I have, &c, John Blackett, Esq., Acting Engineer-in-Chief, Henry Wrigg. Wellington.

Enclosure in No. 2. Waikato Railway.—Approximate and Comparative Estimate of the tliree alternate Lines from Newmarket to Auckland, exclusive of Stations and Sea Embankments Protection. Domain Line —length, 2 miles 3 furlongs 1 chain. £ s. d. Excavations, 51,760 cubic yards, at Is. 4d. ... ... ... ... ... 3,450 13 4 16,830 cubic yards, at 2s. 6d. ... ... ... ... ... 2,103 15 0 Accommodation Bridge, about ... ... ... ... ... ... 150 0 0 Foot Bridge at Constitution Hill, about ... ... ... ... ... 300 0 0 Timber Viaduct, about ... ... ... ... ... ... ... 3,280 0 0 Accommodation Bridges in Domain, say ... .... ... ... ... 800 0 0 Bridge at Parnell Eoad, about ... ... ... ... ... ... 330 0 0 Fencing and Draining, 151 chains, at £3 ... ... ... ... ... 453 0 0 Culverts, and repairs of existing ones ... ... ... ... ... 180 0 0 Permanent Way, 4,202 yards, at 16s.... ... ... ... ... ... 3,36112 0 Total ... ... ... ... ... ... ... 14,409 0 4 Tunnel Line —length, 2 miles 1 chain. Excavations, 10.529 cubic yards, at Is. 4d. ... ... ... ... ... 70118 8 16,830 cubic yards, at 2s 6d. ... ... ... ... ... 2,103 15 0 Accommodation Bridge, about ... ... ... ... ... ... 150 0 0 Culvert at Mechanics Bay, about ... ... ... ... ... ... 400 0 0 Repairs to present Culvert (large) ... ... ... ... ... ... 150 0 0 Repairs to present Viaduct, say ... ... ... ... ... ... 100 0 0 491 yards of Tunnel to complete, at £30 ... ... ... ... ... 14,730 0 0 Fencing and Draining, 55 chains at £3 ... ... ... ... ... 165 0 0 Permanent Way, 3,542 yards, at 16s.... ... ... ... ... ... 2,833 12 0 Small Culverts, and repairs of same ... ... ... ... ... ... 60 0 0 Total ... ... ... ... ... ... ... £21,394 5 8 2

p.—No. 6a.

Coast Line —Length, 3 miles 3 furlongs 1 chain. £ s. d. Excavations, 125,539 cubic yards, at Is. 4d. ... ... ... ... 8,369 5 4 34,698 cubic yards, at 2s. 6d. ... ... ... ... ... 4,337 5 0 Accommodation Bridge ... ... ... ... ... ... 150 0 0 Culvert in Mechanics Bay for Saw Mill ... ... ... ... ... 150 0 0 Smaller Culverts and repairs of existing one ... ... ... ... ... 210 0 0 Two Road Bridges, about ... ... ... ... ... ... 600 0 0 Two small Tunnels, lined with timber, 313| yards, at £7 ... ... ... 2,194 10 0 Fencing and draining, 243 chains, at £3 ... ... .., ... ... 729 0 0 5,962 yards of Permanent Way, at 16s. ... ... ... ... 4,769 12 0 £21,509 12 4 Summary. £ s. d. Domain Line ... ... ... ... ... 14,409 0 4 Tunnel Line ... ... ... ... ... 21,394 5 8 Coast Line ... ... ... ... ... 21,509 12 4 Notes. 1. No provision is made for pitching the sea embankments in case the excavations at Fort Britomart, &c, do not yield material of sufficient tenacity, and in sufficient quantities for the purpose, so that if pitching becomes necessary, the extra cost would be nearly the same for the Domain and Tunnel Lines, but the increased cost for this purpose would be large for the Coast Line, on account of the greater extent of the sea embankment. 2. There is great uncertainty in the cost of the tunnel, and considerable risk in its execution. 3. The tunnel would make the station for Parnell costly and inconvenient. Henry AVriog, 15th August, 1871. Engineer-in-Charge.

No. 3. Waikato Railway.—Memorandum by Mr. Blackett. The annexed report (15th August, 1871), accompanied by two tracings, is forwarded by Mr. Wrigg for the purpose of enabling the Government to decide as to which of the three lines between Newmarket and the wharf at Auckland shall be adopted. The lengths and estimates are as follows, viz.: — £ s. d. Domain Line, 2 miles 3 furlongs 1 chain ... ... 14,409 0 4 Tunnel Line, 2 miles 1 furlong ... ... ... 21,394 5 8 Coast Line, 3 miles 3 furlongs 1 chain ... ... ... 21,509 12 4 The feeling being decidedly against the Domain Line, on account of it passing through a favourite place for recreation from end to end, the choice may lie between the Tunnel Line and Coast Line. It will be seen that their estimated costs are nearly equal, and that Mr. Wrigg notes the risk of undertaking the Tunnel Line (on which I havo already strongly reported), and the consequent uncertainty of its cost. The objections to the Coast Line are, its extra length (one mile on a dead level), and the doubt that exists of the material of which the cliffs are composed, and which will be used in forming the embankment, being able to stand the wash of the sea or harbour. I think this need not be dreaded, as a good wide flat slope can at first be given to the embankment, which afterwards may be protected with hard scoria rock brought down from Newmarket at a small expense after the line is opened and applied to those parts needing protection ; it may be placed at random and not pitched, and will thus resist the action of the surf better, and cost very much less. 22nd August, 1871. J. Blackett, C.E. ■

Mr. Blackett, —Can you tell me whether the coast line would reclaim tidal land in Mechanics Bay, and, if so, what extent ?— \V. Gisborne, 24th August, 1871. Mr. Gisborne, —The plan shews that about 10 acres would be reclaimed in Mechanics Bay ; but I should not think that the full cost of reclamation is included in estimate. The bay, however, is very shallow, and ■would not require much filling. —J. Blackett, C.E., 24th August, 1871. Eor His Honor Mr. Gillies, —Would you favour me with your opinion on these alternative lines ? My own opinion inclines to the Coast Line.— W. Gisborne, 24th August, 1871. Looking to the relative cost of the Tunnel and Coast Lines, and their relative risks and advantages, I have no hesitation in giving my opinion in favour of the Coast Line.—T. B. Gillies, 26th August, 1871.

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