LESSONS FROM TARANAKI.

Putaruru Press, Volume II, Issue 35, 12 June 1924, Page 2

LESSONS FROM TARANAKI.

ROAD-MAKING METHODS. Morrinsville Settlers Views. The roading problem in the many counties is one which has given the councillors considerable food for thought, and the Taranaki roads have been held up as examples of what is desired. The impressions and facts gleaned by Mr. F. Colbeck, of Kura* nui roa.d : , Morrinsville, should be of value.

Mr. Colbeck was greatly taken with the Taranaki roads over which he went for hundreds of miles without a jolt. Thirty miles an hour appeared to be an average speed for motor vehicles, which seldom travelled below that pace. The roads were also easy on the tyres, which were worn right down to the canvass; in fact, he travelled with one man on whose tyres there was not a vestige of rubber, and who undertook a lengthy journey without fear of a puncture or blow out.

Mr. Colbeck considered that the costs of laying* down these roads were reasonable, but they required maintaining tain them,” he added. The tarred reads were lightly re-ooated every second year. There was one road which had not been touched for four years, but it was considered bad policy to leave a road that length of time without attention.

It was “tommy rot” to say that there was not as much traffic in Taranaki as there is in the Thames Valley and Waikato districts. Mr. Colbeck maintained that the Taranaki district was more closely populated, manure was used more heavily, especially in North Taranaki, and most of the dairy factories manufactured cheese, necessitating the carting of the whole milk, yet there was not a sign of a rut. The methods adopted for laying down roads were tar sealing, tar grouting and bitumen penetration. Tar grouting was better than tar sealing, while bitumen was an improvement on the grouting, but bitumen was considered to be dangerous for horses in frosty weather.

In an interview with the engineer of the Waimate West county, Mil*. Colbeck obtained figures showing the costs of laying down the roads, and the following details in connection with the operations in tthat county:—

“ The total area of the county is 72 square miles, 46,000 odd acres. The total valuation is £1,441,639. There are only two ridings in the county, and the rate is a penny and a half in one riding, and one and three-eighths in the other. The traffic is very heavy. The county is away from the railway, the nearest point being eight miles away. There * are nine or ten heavy motor lorries over out main road every day. The roads also carry a considerable amount of traffic from an adjoining county, who have to cross this county to get to the railway. There are no toll gates. The motor and other traffic became so heavy that it was found almost impossible to make and keep ordinary metal roads with grinding surface out of a reasonable rate, so it was decided to go in for something more permanent and to tar the whole of their roads. There are now just on 70 miles of tar roads, some of which have been tarred for over four years. The estimated cost of keeping these roads the wide with the narrow and the main with the bye roads, is 13s per chain per annum.

“ The county adopted two different systems, tar-grouting* and tar-seal-ing. The former is much the better job, and only costs about 20s per chain more than the latter. The method followed when tar-grouting is as follows: First metal or remetal toads, giving it whatever coat of metal it may require according to the foundation. You do not require the same coat of metal on a road that is going to be tarred that you would if it was only for a grinding mad. After the metal is spread it is well rolled. The tar is then sprayed evenly all over the surface of the metal and this is well covered with crushed, chips or good clean riverbed shingle. The traffic is then allowed “to run over it for a few days before giving it is second coat. First sweep the road with a horse brush leaving any surplus shingle at the edge of the tarred portion. This can be used the second time. When the road is thoroughly clean it is given its second coat, and this is well covered with shingle. The road is then ready for the traffic. Care must be taken from time to time to keep any bare patches of tar covered. The cost of the first coat is about ninepence per square yard; the second about six and a-half pence. The first coat requires a little more tar than the second. “ Tar sealing is a system adopted when taring* a road that lias been

laid down for a time, and which has a good even though rough surface, say a road that has been laid down for a year. First it is very important that the road is very clean. It must be well swept and be free from dust or any other dirt which would prevent the tar from getting a good grip on the road. The road is then sprayed with prepared tar. A 12ft road requires about 30 gallons to the chain. This is covered with shingle. This road is always given its second coat the following season, and then does not require any further attention for at least two years, very often three seasons, according to the traffic on it- The first coat costs abut eightpence and the second about sixpence half-penny per square yard. Everything* depends first upon the tar preparation used.

“ Points to be observed while taring: The road should have a good even surface, and be quite clean. The tar should be very hot and sprayed on evenly, and not allowed to drip in patches about the road. The shingle should be clean and of a sharp, gritty nature, and must be spread on the tar lightly at first, not thrown on in heaps or thick. This tends to push the hot tar up into pockets, and causes lumps to form on the road. This .is very important.” The costs per chain of laying the tar sealed and tar grouting roads, 15ft wide, are as follows: — Tar-grouting.—First coat: 40g*als. of tar per chain at Is gal., £2; 2yds shingle at 6s yard, 12s; labour, 6s. Second coat: 25gals. tar, £1 ss; li yds of shingle, 9s; labour, ss. Total, £4 17s. Tar-sealing.— First coat: 30gals. of tar, £1 10s; l£yds of shingle, 9s; labour, ss. Second coat, 12 months later: 20gals. of tar, £1; I.lyds of shingle, 7s 6d; labour, ss. Total, £3 16s 6d. Extracts from a letter sent recently from the clerk of the Elt-ham County Council to the chairman of the No. 7 Highways District Council gives an indication of maintenance costs. The letter states: “ I have taken the total expenditure on the Eltham road for the last four years, which works out at an average of £l3O per mile. Of course there is the amount of traffic, width of road, and the standard of maintenance to be taken into consideration. Comparing our standard of road and maintenance with some of the socalled .roads in the Dominion is not much of a guide. Presumably the Highways Board intend to maintain main roads to something* approaching our standard, not to the standard of those costing £52 or* less. There are also other factors that govern the cost of maintenance, namely, the cost of materials. Many of our roads cost us close upon £1 per yard for metal by the time it is placed on the road, whereas some counties are favoured in that respect, and can procure supplies, which are frequently put down just as taken from river beds at a very much lower cost. The figures given £l3O per mile include all work done on the road, water tabling, tarring and metalling, and also attention to drains, culverts, etc. The Eltham road cost approximately £3OO per mile to maintain', previous to the advent of tar sealing, showing the weight of traffic the road has to bear, and is sufficient justification for the contention that tar sealing has considerably reduced maintenance costs. Boiled down, the fact is, that a first-class article cannot be had for a shoddy price. The Eltham county aim at a first-class road, and expect that a proportionately larger price will be required. I suggest that many of the other parts of the Dominion in estimating maintenance cost, have a very different idea of standard of roads, and consequently the comparison made by you would not be of very great value. The estimate we have given does not include any interest on sinking fund.”