water cistern lid freezing???

[user.69169]

Forst starts on top of the ground and moves down and across.

That iron lid is going to freeze first.

You make yourself a rubber gasket that fits the mating surfaces between lid and frame first. Then you trench about 2 feet down a couple feet back from the riser and drop 2" foam in the trench for a frost fence.
Put about 4" foam board over the iron lid and you should be home free.

 

[777777]

I have a cistern under my garage. Did as suggested by Dave1949 and ran an ABS pipe capped with a screw top. Screw top is just screwed back on but not very tight so water hauler can get it on\off easily. Put vaseline on the threads in the winter to prevent freezing. Works like a charm and has for last 5 years.