ROADS THAT LAST

Evening Post, Volume CVI, Issue 57, 5 September 1923, Page 6

ROADS THAT LAST

CUTTING THE REPAIR BILL

A COMPARISON OF MAINTENANCE COSTS i NEW; SURFACING LAID TO DATE: The. big bituminous paving plant on orderT-for the City Council should arrive m Wellington in the • course' o{ a few .•weeks now, for a report received by the Corporation states that it was shipped irom New York on' 20th August. It rwill.be of interest in the meantime to look over in a general' way' the work that has been done by the small paving plant in the Corparation yard at Clyde quay, since it was erected. a couple of years ago, and also to take', a second look over the work with an eye.parti-, cularly to maintenance costs on perman-' ent surface roads, as with those .of the old style metal roada; to consider the savings brought about by better roading. The Clyde quay plant> of 'the stationary type, was purchased for tar macadam work, but last year was adapted to bituminous mixing, and, though not specially well equipped for this class of roadinaking, lias turned' out a considerable quantity of first-class surfacing.

Wellington in the early days -was ■very well content to bump its carts and ;wagons along over plain beach tracks, over grass tracks just as they might happen to be, and over the ruts when the grass wore away. Clay, roads came I next/'.good dusty roads in summer, right •muddy roads -in -winter, too dusty and boo muddy to be long acceptable. Mac-adam-roads laid down casually enough by filling in the worst mud holes with beach'metal followed on, and after them again macadam roads laid on a definite plan, and each new road was a pretty fair road as roads went at the time of its laying. Probably had the motor industry not boomed anead as it has in the comparatively few years since its beginning—very few indeed, when one considers that it is only about twenty years since the first car was brought to New Zealand—macadam roads would\still have been good enough for Wellington, but the motor, here as elsewhere, has called for new roads and better roads. Wood blocking in heavy traffic streets was the first great advance made upon macadam, but wood blocking is- a costly surfacing,' and as such cannot be extended beyond the streets of the^ city area proper. Tar macadam is good,;but not good enough, and so will be passed by in general roadwork in the future. Bituminous paving is now conamical surfacing may catch the eye sidered to be the finest surfacing at available for city roading. By and by a still more lasting and econof the Corporation's engineers, but unS,il then bitumen will head the list of better roads. ■■■'■' ■ ■ A NEW POLICY. The change from, tar macadam to bitumen was recommended by the late City Engineer, the late Mr. W. H. Morton, who saw the process.in. application in America, and was impressed by the remarkable wearing qualities o£ the surface, the comparatively low cost of construction, and the low maintenance costs,- far lower than those for macadam xoads^ ■ and considerably lower than for tar macadam. The concrete road as now laid in the States also requires next to 110 attention once it has been laid, and Is probably as everlasting as any other roading, but a bitumen road, Mr. Morton considered, has the great advantage over the reinforced concrete road in that when sewers, water mains cable, or any other of the half-dozen or so street : reticulation services have to be attended to, the surface can be taken up with much greater economy, and can be again laid down without noticeable joints in the patching, whereas when the original concfleting has been broken it is a difficult job to hide that fact, or, indeed, to return the surface in as good a state as it was before being broken.

SOME OF THE WOEK DONE. Tha Clyde quay plant commenced operations in October, 1921, practically two years _ago, and the first city street treated, with, tar macadam, was Dixon street, from Willis to Taranaki street. Since then tar macadam surfacing has been laid down in Lambton Station square, Hunter, Eeatherston, Harris, Brandon, Johnston streets, and through, the Seatoun tunnel, and, with the exception of a portion at the extreme north end of Featherston street, the surfacing has been eminently satisfactory as tar macadam goes. The bad patch in Featherston street was laid down in June of 1922 during unfavourable weather, and, moreover, there was at that time a somewhat peculiar, change in the class of tar available, and those two factors combined to take away from ,the; thorough success of the work. .Motorists may complain that the surfacing through the Seatoun tunnel is not ideal, but in that case it was rather the foundation than the surfacing that was at fault for the concrete road bed had already' developed "waves".when the tar macadam was laid down.

In October last it was decided to* discontinue the tar macadam process and to adopt bitumen paving as recommended by. the late Mj. Morton, and when the alterations had been made to the plant a start was made in a small way largely hy way of experiment, in the laying down of a portion of Kent terrace, and also in the paving of a part fSt Til StreeJ" Those experimental lengths fully confirmed Mr. Morton's recommendation, and plans were laid for bitumen reading for the city generally:'! Cambridge terrace was taken in hand without delay, and that strip of Jervois ?u ay'Ti rOrS 1 T^ 11 the lines to the old Te Aro station were removed was treated. Bitumen was also employed m the finishing-off of tram tracks after the renewal of rails in "Willis street and Jervois quay. NEWTOWN TO LAMBTON. As the new paving laid down ia scatter over a fairly wide area it may not appear at .first to amount to very much sifter all. a bit here and a bit there, but those bits add up to 44,200 square yards of surfacing, and that is equal to over three miles of continuous paving- 24 feet wide, and that again is equaf to 24ft stnp from the Newtown Park to Lambton station, a very fair stretch of roading, indeed. The cost, worked out at an average of 6s per square yard, which, as modern roads go, is considered altogether satisfactory. Only a small part of that new roading, however, is of bitumen, and the cost of that paying will be a little higher, in the neighbourhood of 7s 6d per squar yard, tut the better return will, it is contended, thoroughly I justfy the extra expanse in the long run. J.ne surface will last very much longer and the repair bill .will be very much lower, just as maintenance costs for tar macadam roads are much lower than tnos& for macadam surfacing. AN EXAMPLE— DIXON STREET. As a practical example of the savin* of maintenance costs 'by the use' of tar macadam Dixon street may be cited, but

as a matter of fact the illustration is not quite fair to tar macadam, for the reason that Dkon street bears far .heavier traffic to-day than it did two or three years ago, before the Milk Depot was opened, and also before several big warehouse buildings now standing were built; for that reason, however, the example is all the more striking. For the five years prior to the laying down of tar macadam, the maintenance cost for that street amounted to, roughly, £295. Since the new paving went down not one penny has been spent on maintenance and repairs, though a topdressing and a few minor repairs are to be carded out within the nest week or so. .- That, moreover, .is with a tor macadam surface^ and tar macadam has not tne Jife of bitumen. It is -essential that water should be kept out of the mixture, and a sealing, coat will probably have, to be applied to tar macadam roads every two years'or so, bitumen being the material to be used, but in the case, of wood-blocking,-.a top-dressing m-IrV 5 given every '• year- Bitumen wIU lead again in this respect, as it is expected that a top-dressing will not iw required more often than once every five years. ,

■The aim. is to build, even iat somewh™.markedly greater jnjtjai expense a road that calls for a minimum of repair, for every pound saved in that manner is a pound to be expended upon the laying down of new surface. If JJixoti street, a short street and'not a particularly heavy, traffic street until 5. U Qnn .recS ntly- can- eat up practically ±■300 in five years, then it is obvious that the repair bill for the city streets generally were they left as metal roads, would tot up to a very tidy sum. If Dixon street is a true index, then better roads will pay. Wellington very well infW. $ ? Peimy has been spent on Cambridge ten-ace since its new surface ZZu h foWni "° Very lonS P^iod certainly, buWhen the surface was of metal macadam, the annual repair bill

' THE END OF DUST. Permanent paving will mean another very considerable direct saving to the thTdn t'° n -by Practi<"»y eUminatnl the dust nuisance. It does not of course cost anything to have any Amount of dust and dirt about the city, but it does cost good money to clear it away. The Featherston street area was one of the worst, if not quite the worst, dust nuisance areas in the city. Now it is one of the cleanest, and to-day there is not enough street-cleaning work in that block to justify the retaining of all the men who a year-or two ago were kept quite busy enough, and even so could not keep the block aa it should have been. One dray and two men have been taken off and transferred elsewhere, and ml 2™ meaDS a savin 8 of something hke £500 per year on the block. That \^u' J .l S for one P°rti°n of the city. With the mam city streets paved and Thorndon quay and the town end of the Hutt road attended to, Wellington may become almost a dustless city, so much the more comfortable to live in, so much the more healthy. THE PROGRAMME. Providing the weather is favourable a start will be made again next week, with the Clyde quay plant, and the unI treated s tnp of macadam in Cambridge .terrace will be;7taken in hand. It'was \ originally intended that this strip should be utilised as a parking place for tramcars at Courtenay place, but in view of strong opposition that plan has been abandoned and :the parking line will bu placed on the Kent terrace side of th» [ reserve, ■ cutting into the reserve itself. and thus leaving the roadway "full width' Nothing, however, will be done till the weather;- settles.,down^for:if bitumen■■ is. put down under bad' weather conditions it. refuses to stick and may be peeled off like linoleum. The bitumen year is normally from October to May, but while the work is going on the progress i* fairly rapid. The new plant, working in conjunction with the .present machinery, will enable the work to be speeded up' about four times.

Other streets on the programme arr> Clyde quay and Clyde quay' square Wakefield., Victoria, Mercer, TaTanaki, Waring Tayor, Willeston, and Grhuznee streets, part of Tinakori road, and Thorndon quay, ..but, in> several of those streets tram- tracks are to be laid and paving will be held back accordingly. It is possible that portions of Thorndou quay will be straightened out before the new roading goes down. That programme may be extended almost indefinitely, for Wellington has many miles of streets, and though, of-course, there is no intention of extending the bitumen treatment to each and every street, many more than those mentioned above will be treated in due course. . Several of the suburban roads, for instance, will be given a new coating, the Newtown end of Constable street, for; example, and' when all city streets and suburban roads of importance have been dealt with'there are still the sea drive roads, and still the Hutt and Day's Bay roads, but just when the Hutt road will be taken in hand is not yet definitely decided. At any rate it will not be the last on the list. .