BACK TO METAL

Hauraki Plains Gazette, Volume XXXVII, Issue 4925, 13 January 1926, Page 4

BACK TO METAL

THE CHEAPEST SYSTEM.

DECISION OF COUNTY COUNCILS

"You can have all your bitumen roads,’’ declared a Wellingtonian the other day, adding, “I have just been on a gravel, road from Buhnythorpe to Feilding that beats the band. Absolutely wouldn’t a,sk for anything better. Best riding I ever struck !” The road, mentioned is in Oroua County, and is one of the highways which Mr Harding, the county engineer, is maintaining on modern lines at a cost of about £7o' a mile per annum,’and a considerable mileage so maintained in the county is, stated to be carrying a,n average traffic of 400 vehicles a day. In consequence of the highly satisfactory results obtained, Oroua. County (states an exchange) has decided to abandon its £70,000 loan proposals for bitumen surfaces indefinitely.

Word now comes that ,the neighbouring Kairanga County, comprising the area around Palmerton North, is having equally satisfactory results with improved gravel maintenance. Kairanga County has. laid some miles of excellent tar and bitumen-sealed roads at a cost of about £2OOO a mile, and the County Council recently secured authority from the ratepayers to, raise a loan of £54,000 for the purpose of laying bitumen surface on a further 20 miles of ro,ad. So highly satisfactory are the new 1 gravel maintenance methods proving that on the recommendation of the county engineer (Mr Menzies) the Kairanga County Council is also deferring indefinitely the prosecution of its bitumen road surfacing scheme. AN EXPERIMENT TO WATCH. The Oroua and Kajranga roads are worth the closest attention of everybody interested in .the good roads, movement in the Dominion. It was from the United States that we learned of the high carrying capacity of suitably maintained gravel under motor traffic. Many persons have been inclined to dismiss the story of what has been achieved- in America as a myth, or, at any rate, a gross exaggertaion. Happily, some engineers decided to try it put for themselves-, and there is very little doubt that what has been done by. Mr Harding in Oroua Count}' and Mr Menzies in Kai■ranga County con be repeated over large areas of the North Island.

If this, Manaw.atu district experience means anything, it means that at a very early date, w)th no- capital expenditure beyend a modest investment in a proper equipment of plant, we can have good roads up and down the whole countryside, with surfaces that provide pleasant .travel add reduce wear and tear to, a minimum:.

For some years, past the policy of working up from .the cheap end of road-making has been advocated. For a time it seemed that ,the only practicable advance was; to give the existing road surfaces some form of treatment with bitumen or tar to water--proof the surface and prevent it from unravelling under 1 motor traffic. Then word came of the highly successful results being obtained with untreated gravel in the United Stales, and every endeavour has since been made to give the fullest publicity to the methods adopted and the results attained by working on these lines. It was significant that after their tours abroad .with Mr Tindall, engineer to- our own Main Highways Board, and Mr W. Calder, chairman of the Victoria County Roads- Board, returned- as thoroughly convinced advocates of better maintenance, and particularly gravel maintenance, as the key to the whole rural roading problem.

’ A COMPARISON IN COST. Kairanga’s, former bitumen roads at £2OOO a mile meant an annual expenditure in interest and sinking fund of about £l6O a mile'. With maintenance added the annual, cost of such a road would be in the vicinity of £2OO a mile per annum. It is thus apparent that if good gravel, surfaces can be maintained for £7O or £BO a mile per atnnum a saving of £l2Ol to £l3O a year on every mile of. road wi’l-be effected. In reality the saving will probably be even greater, as the allowance above of £l6O for capital charges is on a b:',sis, of 5% per cent, for interest and per cent, tor sinking fund. A loan on such a basis would only be wiped out in 20 years, and evidence is lacking that the type of bitumen surface would last any such time. It is interesting to- note in connection with the above figures that the annual capital, cost of the bituminous concrete paving done last season in Hutt and Petone worked out at.£Boo a mile, or more than ten times what Oroua is spending on gravel maintenance. Even supposing'the city engineer’s original estimate of £4OOO a mile for 3%in bituminous concrete on rural roads had been realised, the capital, charge on the basis quoted would be £320 per mile per annum, which, with the official estimate of £35 a mile for maintenance added, would make a total annual cost of this type of -road £255 a mile per annum, or seven times what Oroua County is spending. The project of the Wellington and Suburban Highwiys Board for a provincial scheme of hot-mix roads, in face of these figures, would have the extraordinary result of restricting the mileage of good roads procurable for a given sum of money to one-seventh of what could be attained by Orona’s methods. Such a minute mileage of high-class -roads, with -the other roads neglected to provide it, would give satisfaction to no one;. If the Main Highways Board is satisfied that the results now obtained in Orpua and Kairanga, counties are as successful as has, been represented itt would be an excellent move to- arrange travelling facilities for local body members and county engineers and overseers to inspect the roads and make themselves familiar with the methods employed- A system of maintenance that opens the door to the immediate improvement of almost the whole body of our rural roads is worthy of the very fullest investigation by everybody concerned.