Paul,

The 55 gal barrel sounds like a good idea, wish I had read your post a couple years ago!

When I had the concrete poured for my waterer area (it's on a slope and needed concrete), I didn't have one of those insulated culvert sections when needed, so I wrapped 6" building insulation around the outside of the culvert shown before they poured the concrete. 

I'm not sure how much good it is doing but must be somewhat effective.  The black plastic culvert shown is about 6 ft deep. The 4" PVC is over 8 ft deep with a 90 at the bottom. The experienced folks that did the waterline trenching in WI tell me they always run a heat tape around the vertical pipe just for insurance. It has a thermostat but they said it doesn't need to be plugged in unless the line should freeze...I wrapped some insulating tape around the top.

FWIW. Jim at Dawn 

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