ROADING METHODS.

Otago Witness, Issue 3808, 8 March 1927, Page 72

ROADING METHODS.

material too expensive. VISITING ENGINEER’S CRITICfISM. A . WELLINGTON, March 4 en gmeer, at present visiting New Zealand, passed some interesting comments on our reading methods in the course of a con vcrsation. I n Auckland City, he said, he found a remarkable view that the only alternative to a most indierently maintained macadam was a costly concrete pavement. In Wellington city an equally remarkable view appeared to prevail that the only alternative to badly maintained macadam was an expensive bituminous concrete, or hot mix pavement. In neither city did there appear to exist among the council members any appreciation of tho intermediate forms of surface treatment between ordinary macadam and these highclass types, of pavement. Yet, except for a very limited mileage of main road bearing heavy traffic, it appeared to him that there was no economic, or engineering, pistificatmn for these high tvpes of paving, ibis lack of appreciation of the value ci the intermediate types of paving with bitu minuous treatment struck him as a very extraordinary thing, and he could not f ' the life of him see how the money cor.! be found for any great mileage of e:the cement, concrete, or bituminuous pavin - Speaking generally, he was surprised at th general excellence of the roads of the Th minion, in view of the big mileage cf them and the comparative sparseness of the population. Certain points had struck him connection with tho highways scheme. The impression he had received was that the attitude of the Hignways Biard towards the local bodies was more of criticism. That would be overcome when tho Highways Board got more into its stride. ! rom what he could see the board was handicapped by being so much under the tutelage of the Public Works Department. Instead of having specially qualified road engineers of its- own in charge of .the various areas,, the. board operated through the district engineers cf the Public Works Department. These engineers had a great deal of other work to look after, and it did not appear to him that they included among their number any specialists in road work.

The motor traffic was leading in many districts to some form or other of bituminuous treatment. So far as he could discover the Public Works Department's engineers included very few men who had any wide experience of this class pf work. Many of the county engineers knew infinitely more about bitumen than did the Public Works : Department’s engineers, who were called upon to approve or- condemn, the county work. This was a remarkable state ot affairs, and not conducive to securing the best results from the main highways scheme. It appeared to him that- it would be greatly, to the advantage of the scheme if the Highways Board divided each island into, say* three or four districts, and placed each under a really expert road engineer, with wide practical experience of the t,eclmic of the various types of road surfacing and up-to-date maintenance methods.

.On the whole, his impression was that the road transport of the Dominion deserved more attention than it received. The Dominion, according to the Official Year Book, spent about £8.000,000 : on railway transport. If the expenditure onroad transport were analysed it would probably be found tt> amount to double this ’ sum—that is, including road maintenance, interest on the capital cost of construction and the- operation expen ;es of the 150,000 motor vehicles now on tne roads of the Dominion. The campaign for increased efficiency in the Railway Department might well be extended to the road transport side which, in comparison, was a Cinderella department. The visitor, in conclusion, said he thought the Highways Board had taken a. very wise step lately in treating expenditure on bitumen.sealing as maintenance, and not as construction work to be defrayed out of long-term loan money. This class of work,while very necessary'* - and. profitable, when the wear and tear on a road exceeded ,a certain point, was purely temporary in .its character, and the practice of some local bpdies of doing it out of loan appeared to him to be niqst unsound. In fact, the practice an New Zealand seemed to be to extend the repayment period for the loans over a far greater length of tiqie than there was any reasonable expectation of even the expensive types of paving lasting. This was a matter which might lead to heayv financial burdens later on when a new loan had to be floated to relay a pavement, and the payments on the' old loan stilb ran on, double-banked with the new burden. Such a state of things must lead to great irritation and dissatisfaction.