I get ice dams. I've chopped them, I've salted them, and last time
I ran hot water over them. I like the last method best.

My current set up is a gutter cleaner along these lines
http://www.idealtruevalue.com/servlet/the-128449/Detail

My gutters on the north side of the house are about 22 feet up. So I
have it duct taped to a swimming pool extending aluminum pole.

I want to eliminate some of the Rube Goldberg-ness of that setup and
extend the handle of the wand down to the ground. It will be a
little lighter than that rubber hose + the pool tool, I'll have a
shutoff right at hand, and it will keep my hands warm with the hot
water.

Will [1/2? 3/4?] thinwall conduit survive very long with water running
through it a couple times a year and otherwise being stored in a
basement? And is there a way to make a good sturdy, watertight
connection between two sections of it?

What else might be strong enough to poke around a stick 22 feet long
nearly straight up in the air without being too heavy?

There's a pretty decent scrap yard nearby that I haven't been to in
ages- maybe I find something there if I know what I'm looking for.

Jim