Checking out the neighbourhood’s newest pole
Today a new cedar utility pole stands identically in the place where the old pole was knocked over last night. Only one cut strand of aluminum wire rope and a quantity of sawdust remains to indicate anything out of the ordinary happened.
And maybe cars knock over wooden utility poles in alleys all the time. The incident I’m referring to happened in the alley just behind the Heart and Stroke Foundation’s West Broadway Avenue offices in the 1200-block.
The falling pole didn’t hit one of the buildings in the alley and didn’t appear to knock out power (electric lights, not candles, were on last night in at least two apartments next door to the toppled pole). But the incident was serious enough that crews needed to be on hand from at least 10 p.m. to repair the boo-boo.
The truth, the pole truth and nothing but
I have only seen two varieties of wooden utility poles in Vancouver: western redcedar (WC) and lodgepole pine (LP).
According to a 2001 BC Hydro report: Performance of Wood Poles in B.C. (yawn), looking at Hydro’s total pole population, WC poles lasted an average of 15 year longer than LP poles. WC poles had a maximum predicted mean life of 71 years, while LP poles’ predicted mean life was only 50 years.
Western redcedar also has natural antibacterial properties that lodgepole pine doesn’t and LP poles seem more susceptible to damage from insect infestation. Furthermore WC is better in the wet climate of Metro Vancouver than LP.
But back in 2001 nearly half of BC Hydro’s wooden utility poles were still LP and the 13-year-old report made the point that LP poles provided excellent service in the drier climes of northern British Columbia.
And the winner is…
A 2014 BC Hydro report on pest management of wooden structures declares that western redcedar is now mandatory for power transmission poles, period.
In the back alleys of Vancouver, The LP poles really show their age but old WC pole can look near as naught like new WC poles.
BC Hydro now only buys wooden utility poles that have been sterilized and pressure treated for their full-length, usually using what the 2014 report refers to as “copper chromium arsenate” and the 2001 report refers to as “chromated copper arsenate.”
The new pole installed last night bears both the punch marks of pressure treatment and the greenish copper tint imparted by CCA.
In case no one has ever warned you: don’t lick the wooden utility poles!
The arsenic in the CCA does leech into the soil over time but supposedly in negligible amounts no greater than the naturally-occurring amounts of arsenic in soil.
Burning CCA-treated lumber in a regular fire — fireplace or barbeque. — apparently releases arsenic-laden smoke which does pose a health risk.
Tagging the new pole
It was interesting to see that crews removed the credit card-sized numeric plaque off the old pole and nailed it onto the new pole.
Initially I was surprised. I only remembered the type of card that was part of an obsolete location system — a way, thirty years ago, to know the absolute geographic position of a pole.
Lots of utility poles still bear such cards but a succession of inexpensive GPS receivers have rendered such on-pole records of geographical location unnecessary.
I forgot there are three kinds of cards. The kind on this pole only contains an inventory string. I refreshed my memory by reading one of my own posts. Click the images to enlarge them.