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Sheldon

wrote:
Hello.

I'm putting up a yard light at my acreage, and I have a question about
the actual installation of the light pole.

I have a typical timber pole, about 35 feet long. A friend will be
helping me with his bobcat to auger a 12" post hole for the pole and
install the post within the hole.

I have a couple of questions regarding how to hole and how to backfill
it.

First, how deep should I install the pole? Does it need to be at least
as deep as the frost depth? I'm thinking the hole should be about 10
feet deep for my area (central Alberta, where the frost penetration
depth is typically about 8').

Second, what would be the best method to backfill around the pole once
it has been placed in the hole? I'm thinking there are two options -
using concrete or tamping in crushed gravel. Does anyone have
experience with these methods? The concrete would be a pain as we'd
have to brace the pole some way until the concrete has set. I think
that the local utility companies use the crushed gravel method when
installing new power/phone/lighting poles.

Any help is appreciated!

Never install any wooden pole/post in concrete... it will heave and it
will rot. Set in gravel or sand or any material contribuing to good
drainage, then back fill with whatever soil was removed. Only metal
posts/poles get set into concrete, and even those should have good
drainage material at the bottom or they will heave. If your frost
penetration is 8' than you need to go at least that depth, especially
with wood.