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Utility poles

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Re: Utility poles

#21

Post by ggm »

In Australia we have a life extension program for hardwood poles which slides a steel formed sock/support down the side to stabilise it for many a year more after a hard life.

We had some issues with corrosive dog wee. Tar treatment sometimes works. Also steel collars to keep possums off the top structure.

In Europe there are other platforms above the transform and wire complex for bird nests. Storks, cranes all above the risky bit.

Aussie poles are made from wood which is harder than nails. Unbelievably strong stuff which years of soaking in very nasty chemicals defends from termites which are ubiquitous.

Re: Utility poles

#22

Post by grzm »

gilbetron wrote: post #19

My dad was an electrician for about 40 years - one story he told me when he was training apprentices years ago was teaching them how to climb telephone polls. You wore boots that had spikes in the side of them, but when climbing, you had to keep your knees away from the poll so the spikes would dig in properly. Unfortunately, when you get to the top of the pole and look down, some people panic due to the height. And…

Nit: s/poll/pole/g

Re: Utility poles

#23

Post by aaronarduino »

sevensor wrote: post #9
joeframbach wrote: post #3

Old utility poles can be reused in many ways too, but they must be outdoors, and not where it can have direct contact with people. Back in 2003 I called a local electric company if they could donate a few used poles to be used as beams for a bridge I was constructing for a local park. They we're happy to oblige. You can sometimes see these poles used in retaining walls and buried alongside hiking trails, used as wate…

> and not where it can have direct contact with people. Could you expand on that? My elementary school had a playground structure made of old utility poles. Other than getting pitch on our clothes, they didn't seem particularly hazardous.

Probably because the gasses that the poles produce when burning are prohibited by fire code.

Re: Utility poles

#24

Post by Faaak »

sevensor wrote: post #9
joeframbach wrote: post #3

Old utility poles can be reused in many ways too, but they must be outdoors, and not where it can have direct contact with people. Back in 2003 I called a local electric company if they could donate a few used poles to be used as beams for a bridge I was constructing for a local park. They we're happy to oblige. You can sometimes see these poles used in retaining walls and buried alongside hiking trails, used as wate…

> and not where it can have direct contact with people. Could you expand on that? My elementary school had a playground structure made of old utility poles. Other than getting pitch on our clothes, they didn't seem particularly hazardous.

It may be the same thing as railway sleepers: they are treated with Creosote, which is not a very good chemical

Re: Utility poles

#25

Post by Dangeranger »

jmspring wrote: post #17
Dangeranger wrote: post #15

Back around 2010 I worked for a company which built software to catalog residential distribution utility poles and the lines emanating from the poles to the houses. To elaborate on a few of the statements from the post Poles in my neighborhood tend to have consecutive numbers. I don't think this was carefully planned. The sequential ordering of pole numbers is definitely planned, and fits in with a scheme developed b…

The pole numbering also helps in things like the work PG&E has to do checking for trees and other obstacles posing a risk to transmission lines. The report indicating where the work needs to be done (for instance to cut down a tree) uses the pole number as a point of reference.

Yes, I am intimately familiar with this as this was also part of the services that I was involved in delivering. One of the deliverables for utility clients we provided was every "fall in" or "drop in" line violation for high power transmission lines, including their "between" location in relation to adjacent poles on the corridor.

I could talk about this subject for hours so let me know if you have any other questions.

:)

Re: Utility poles

#26

Post by jedberg »

CaptainDecisive wrote: post #8

I did some work for an electricity utility and they wanted to get the pole IDs described in the article into our database, alongside the GIS data. The client explained that getting the IDs was kinda difficult and there were several different data sources for the various regions they provided service to. By and by we found a guy there who knew how everything worked and promised he'd get us the data that we needed - wh…

> that there were perhaps 1000 poles out there that weren't on any of there maps

I can totally see how this would happen. When I bought my house, the power/utility lines were hanging about four feet off the ground in my backyard. Apparently the previous owner didn't care.

I called the utility company to complain, and they sent someone out with a new full size pole, who basically just shoved it in the ground in the corner of my property to prop up the lines.

As far as I can tell, there are no identifying marks anywhere on the pole. No label, no inspection, no nothing. Except a sign that says "Danger, do not put ladder on this cable", which is on the fiber optic cable that runs along the pole.

Re: Utility poles

#27

Post by hexane360 »

pan69 wrote: post #6

I have always wondered about utility poles, they always seem very fragile. Why not just stick everything in the ground?

Insulation is expensive. Furthermore, with AC you have to worry about the impedance of whatever you use as insulation. Basically the whole wire starts to act as a big capacitor, leaching power. (1)

I found some cost estimates: "The estimated cost for constructing underground transmission lines ranges from 4 to 14 times more expensive than overhead lines of the same voltage and same distance. A typical new 69 kV overhead single-circuit transmission line costs approximately $285,000 per mile as opposed to $1.5 million per mile for a new 69 kV underground line (without the terminals). A new 138 kV overhead line costs approximately $390,000 per mile as opposed to $2 million per mile for underground (without the terminals)." (2, page 17) Also, diagnosing and correcting faults is much easier above the ground than under, and you'd be surprised how often jackasses with backhoes take out underground infrastructure.

[1] https://en.wikipedia.org/wiki/Characteristic_impedance

[2] https://psc.wi.gov/Documents/Under%20Ground%20Transmission.p...

Re: Utility poles

#28

Post by Dangeranger »

ggm wrote: post #21

In Australia we have a life extension program for hardwood poles which slides a steel formed sock/support down the side to stabilise it for many a year more after a hard life. We had some issues with corrosive dog wee. Tar treatment sometimes works. Also steel collars to keep possums off the top structure. In Europe there are other platforms above the transform and wire complex for bird nests. Storks, cranes all abov…

As I understand it one of the largest concerns in AU are the wildfires damaging circuits connecting the disparate grids. There was some conversation about replacing some of the network poles with fire resistant poles in order to try and avoid the high number of outages caused by fires during the dry season.

I'd be interested to know how that project went, and if it was successful.

Re: Utility poles

#29

Post by shirro »

ggm wrote: post #21

In Australia we have a life extension program for hardwood poles which slides a steel formed sock/support down the side to stabilise it for many a year more after a hard life. We had some issues with corrosive dog wee. Tar treatment sometimes works. Also steel collars to keep possums off the top structure. In Europe there are other platforms above the transform and wire complex for bird nests. Storks, cranes all abov…

Except for South Australia. I don't know if it was due to termites, lack of hard woods, fireproofing or an excess of steel and concrete but we embed concrete between two steel beams to create the iconic stobie pole which has doomed countless motorists. https://en.wikipedia.org/wiki/Stobie_pole

Re: Utility poles

#30

Post by exhilaration »

pan69 wrote: post #6

I have always wondered about utility poles, they always seem very fragile. Why not just stick everything in the ground?

Many newly built neighborhoods do indeed have everything underground. Retrofitting older neighborhoods generally isn't worth the cost.
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