SEALING STEEP ROADS

Dominion, Volume 27, Issue 33, 2 November 1933, Page 10

SEALING STEEP ROADS

Bitumen Surface Possible

WORK ON BOLTON STREET

Bolton Street is to be surface sealed this summer. This work was promised some years ago, but for one reason or another it has been postponed. Now the macadam surface has broken up and the dust nuisance on windy is intolerable. ■ Wellington has many steep streets on the sides of its hills, and one of the problems of the past has been to keep such streets in order. Braked cars cause the wheels to drag and exer.t a strain on the surface that would not exist were the wheels running freely. Only ten years ago it was held that it would be positively dangerous to surface, seal or pave in bitumen these very steep roads. That notion has proved to be fallacious.

In Oriental Bay there are several short streets with a very steep grade. Wilkinson’s Avenue has one of less than one in five, and Oriental Terrace and the Telford Terrace approach are not much better. These have been surfaced within the last two years, and not only has the sealing coat stood up to the traffic, but it has been found that the holding is better for a motor-car than a loose macadam surface such as exists at. present on Bolton Street. Descending" Bolton Street at 20 miles per hour does not feel so safe as descending Thompson Street at 30 miles per hour, yet there is no great difference in the grade. Bolton Street is about one in 5J over the lower half and one in 6 at the top, whereas Thompson Street is about 1 iu 6 throughout. The reason for that feeling of security Is that on the smooth surface all four wheels are gripping evenly, whereas on a broken macadam surface the car is jumping from bump to bump, and has therefore less hold. I When asked if the road would be finished with a rough metal outefop surface, the engineers gave the assurance that such was not necessary; indeed, it was not desirable. The finish would be in a half-inch of bituminous concrete, which would give the desired surface for such a grade.