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Donald Richardson
The stobie pole, that ubiquitous steel-and-concrete adornment of the fringes of our streets and highways, is unique to SA. Although it is reviled by some as “hard” and “mechanical”, it is actually an elegant design solution to a problem; one which uses materials readily available in the state – concrete and steel. Its original designation was, in fact, “the C-S pole”, but it eventually became named for its inventor, James Stobie.
When generation of electricity was started in the 1920s, the insulated copper-wire cables that distributed it had to be either buried underground or carried high enough over vehicular traffic to prevent inadvertent electrical discharge and possible electrocution. The problem with burying cables was always just how deep to go; but, at almost any depth, buried cables are liable to being cut by, say, digging for the foundations of buildings and power outages have occurred from time to time from this cause.
The time-honoured method of carrying the cables overhead is to support them on high wooden poles, but long hard-wood timber has always been scarce in this state. When the limited stocks available from the area south of Adelaide were exhausted, poles had to be imported – mainly from NSW – at a prohibitive cost. And as wooden poles were less than permanent in our termite-infected areas, an alternative had to be found.
James Cyril Stobie (circa 1896-1953), the chief draughtsman of the Adelaide Electric Supply Company (the forerunner of the Electricity Trust of South Australia), registered the patent for the C-S pole in 1924. Stobie-poles are manufactured horizontally; two steel i-beams or u-sections being bolted together. allowing space between them for filling with poured concrete. The pole tapers in width towards the top and downwards from ground level to give maximum stability, strength and ease of erection. It is essentially a most economic reinforced-concrete system; the steel providing the tension which contains the
compressive strength of the concrete when set.
It can be made in a range of widths from a couple of hundred millimetres to nearly a metre and a variety of heights, and with relatively simple equipment. And it can be manufactured onsite in country areas, thus saving transport costs. Although stobie poles are more expensive than wooden poles, where these are available, they have a longer serviceable life – 100 years, compared with 15 to 30 for wood. And they are fire and termite proof. Also, they are stronger and lighter than the all-steel poles that are used interstate.
The first example – less than 10 metres high – was erected on South Terrace in 1924, but soon it was being manufactured twice as high. It was employed in 1925 on the new powerlines from Adelaide south to Willunga and north to Jamestown. In that year, too, Stobie sold his rights to the company for £500. The use of wooden poles ceased in 1926 and the storage yard, at Mile End – the present site of the ETSA building – became the site for manufacturing the stobies. Many thousands were produced after the second world war for the state-wide electrification.
From time to time, stobie poles have been accused of causing serious injury or the death of motorists who run into them but, in fact, their construction makes them able to absorb a good deal of impact because the concrete will crumble and the steel bend somewhat. A pole which collapses completely after a collision strews powerlines over buildings and vehicles, creating a wider hazard. Suggestions that they be moved back from the kerb to reduce injuries from car accidents do not allow for the fact that, when cars run off the road, they usually must run into something – if not the pole, then a building or a person, perhaps. On the other hand, there have been calls for its listing as a national treasure and – in fact – in 2002 it was declared a BankSA heritage icon by the National Trust of South Australia.
Objections to the pole on aesthetic grounds usually come from romantics who prefer the natural to the artificial and the old to the new; but, to hold this viewpoint, they must have little regard the conservation of our forests. One wonders if these are the same people who object to clear felling. One of the first objections to “unsightly” powerpoles was recorded in The Advertiser as early as 1925 – but this was to wooden poles! It is probable that a good deal of the negative appearance of the poles is caused by the untidy profusion of wires that hang from them and, perhaps, their often injudicious placement rather than the poles themselves.
An aspect of the aesthetic reaction to the stobies has been their decoration, mainly by school children. This began in the late-1970s in Prospect, the inspiration of local artist, Ann Newmarch, and spread throughout the suburbs. Many of these decorations are charming and amusing, and they certainly relieve the grey monotone of the concrete but, where they may make the poles less visible to motorists, their ultimate value may be questioned. It is an aesthetic error to treat a functional object as a canvas for free artistic expression without regard to its functional imperative.
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