CONCRETE VERSUS TARSEALED ROADS.

Manawatu Herald, Volume XLI, Issue 2015, 14 August 1919, Page 3

CONCRETE VERSUS TARSEALED ROADS.

. REPORT TO THE KAIRANGA ’ COUNTY COUNCIL.

Some time ago the Kairanga County Council arranged with Messrs Toogood and Alair, civil engineers, to supply a report on the best methods to adopt in laying down permanent roads in the County. A preliminary report was prepared and presented to the Council. At the meeting of the Council on Tuesday, Air Alair attended, and read a voluminous report which had been prepared by Air Toogood and himself. The report look over an hour to read.'

The report went into detail in connection with the cost of concrete and tar-sealed macadam roads, as veil as the advantages and disadvantages attaching to each. The report concluded with answers to the various questions as to whether the 'conditions of agreernent under which Air Craw’s concrete section of road was laid, it was stated that the cost had been exceeded by about £lO per chain, being about £4O as against £3O, mentioned in the conditions of agreement. The next question was as to whether the sample of road laid down by Air Craw was suitable for. adoption for County roads in the event of the Council deciding to go in J'or concrete roads, the answer was that the specifications used in that case must he improved. The cost to construct a similar piece of road in the same locality would be about £42 per chain. The approximate average cost of putting down a concrete road twenty feet in width would he about £5,010 per mile, such estimate to include cost of necessary re-formal ion, side track for carrying traffic during construction and everything connected with (lie work, and all -plant ('including two motor trucks) available. To this, however, it would ho necessary to add 10 per cent, for improvements necessary to Mr ('raw’s scheme. The engineers, however, did not advise a twenty feet, road, as the volume of traffic did not appear to warrant if. Upon liie' question of tar-seaied reads the engineers expressed the opinion that a sound macadam road, tar-sealed and maintained in accordance with the British Road Board specifications, would stand the traffic which might lie expected from the population of the district, as well as rough traffic, if proper regulations of weights and wheels were adopted. Too much restar had been used on the FoXton section, which had resulted in an uneven surface. With reference to the construction of a twenty-foot road with this material, they would not advise offhand the construction of a road of such width, but the cost of such a road on the same basis as concrete would he £.1,682 per mile. In making a comparison of the two methods dealt with, the report advised that a concrete road should not be constructed in the Kairanga County until the cost of maintenance in good order of an eighteenfeet tar-sealed road exceeded to £250 per mile per annum. A macadam road should be tar-sealed wTien the cost of maintenance reached from £IOO to £l5O per year. If done out of rates, tar-sealing could be done with economy, when the maintenance costs would be much lower. It was necessary for the Council to discover what their actual maintenance costs were to-day, and the volume of traffic carried. When this had been done, the Council must decide what value they placed on an improved surface in pounds sterling per mile ' per year, and then . they could decide what type of road should be adopted. In concluding the report stated that if the Council desired to consider the distant future, when maintenance costs would be over £250 per mile, and was prepared to face the financial obligations, then they, the engineers, were prepared to advise the adoption of concrete roads. On foundations which were in any way doubtful special precautions would have to he taken with concrete or tar-treated macadam road. If, on the other hand, the Council desired to avoid the greater financial obligations, and could manage to do certain lengths each year out of rates, tar-sealed waterbound macadam should be adopted. This should not be difficult when it was remembered that the Council were to-day laying down water-bo-und macadam out of rates, and the only additional work required was (he tar-seal aj a cost of about £26 per foot width per mile.

The chairman thanked Air Alair for his comprehensive report, ; and that gentleman returned thanks on behalf of Air Toogood and himself.

It was resolved to have the report printed and circulated amongst the Councillors before it was discussed.