H—4o

The sharp increase in the quantity of petrol consumed in motor-vehicles in 1946 is due to the change in the method of petrol-rationing as from Ist June, 1946, and also to the extra use made of road transport during periods when the railway services have been restricted. ROADS 4. Limitation of Loads on Roads. —Roads may be classified in Classes Three, Four, or Five, according to their standard of construction and ability to withstand the damaging effects of heavy wheel loads. Class Three permits of an axle load not exceeding 5J tons, Class Four a maximum of 4 tons, and Class Five 3 tons. In the case of multi-axled vehicles or trailers the axle load limits are in each case \ ton lower than these loads. The following tables illustrate the extent to which roads in rural areas have been classified in order to protect the surfaces from undue damage caused by heavy loads :

(a) Classification of all Rural Roads at 31st March, 1947

(b) Classification of Main Highways (Rural Sections) at 31st March, 1947

(c) Classification of State Highways (Rural Sections) at 31st March, 1947

In some districts the roads have suffered as a result of being subjected to continued and regular use by heavy vehicles, although the wheel loads have conformed to the limits prescribed under the classification of the roads concerned. The repetition of such loads, especially when road subgrades have been weakened through wet conditions, may sometimes cause damage to the surfaces and even failure of the crust of the road. In such a case the remedy would seem to be rather in the application of temporary restrictions upon the loading of motor-vehicles at times when road conditions are unfavourable than in a general lowering of the road classification. Road-controlling authorities have ample powers to enable the former course to be followed effectively. A lowering of the axle weights to be permitted on any road would obviously reduce the pay loads that could be carried and would result in higher transport costs and charges.

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— Total Formed Roads. Class Three. Class Four. Class Five. Total Classification. North Island South Island Totals Miles. 27,133 22,357 Miles. 5,754 6,648 Miles. 10,256 2,546 Miles. 1,798 278 Miles. 17,808 9,472 49,490 12,402 12,802 2,076 27,280

(This section includes State highways shown under Table (c) following) Main Class Class Class Total Highways. Three. Four. Five. Classification. Miles. Miles. Miles. Miles. Miles. North Island 6,680 3,296 3,041 119 6,456 South Island ... 5,424 4,577 133 42 4,752 Totals 12,104 7,873 3,174 161 11,208

— State Highways. ! Class Three. Class Tour. Class rive. Total Classification. North Island South Island Miles. 2,112 1,686 Miles. 1,275 1,589 Miles. 786 Miles. Miles. 2,061 1,589 Totals 3,798 2,864 786 3,650