When we get ready to work on this I'm going to post pictures so you guys can chime in - you all have the best suggestions!
@herzausstahl - We do have a second pump, but because of the way our pond is plumbed, I don't know how we would use an emergency pump, especially on a frozen pond. That would mean dropping a pump into the pond - impossible in a polar vortex - and having exposed hoses. I did pump out the underground water back up into the bog when I thought this would be a fast fix, so at least the bog is full of water which should keep my plants alive. But that required a sump pump and a garden hose which would work fine in less challenging weather conditions. But no way would that have been enough water movement to keep the waterfall flowing. And an exposed hose would have frozen in -40 degrees I would imagine.
@herzausstahl - We do have a second pump, but because of the way our pond is plumbed, I don't know how we would use an emergency pump, especially on a frozen pond. That would mean dropping a pump into the pond - impossible in a polar vortex - and having exposed hoses. I did pump out the underground water back up into the bog when I thought this would be a fast fix, so at least the bog is full of water which should keep my plants alive. But that required a sump pump and a garden hose which would work fine in less challenging weather conditions. But no way would that have been enough water movement to keep the waterfall flowing. And an exposed hose would have frozen in -40 degrees I would imagine.