strange dock circulator issue

[winterh]

I have 3 separate circulators positioned around my large L shaped dock all controlled by a thermostat timer. Have run like this for many years and never an issue. Something strange yesterday and I don't understand how its even possible. They have not been running because I do not turn on till I get ice. I now have ice and turned them on. The breaker tripped and when I went to investigate 2 of the 3 were encased in a block of ice. How is that possible when they are in water about 5 feet deep? The ice bound the propellors which I assume tripped the breaker. Lifted them out, broke up the ice and they worked again. I have never seen ice form on the bottom before.

[livinthedream]

Are you in an area with little or no water movement? Even with that 5' of ice seems crazy.

[TomC]

I don't think he is saying the ice was 5 feet thick, but rather the circulators were ice encrusted at a depth of 5 feet under water. Perhaps I am wrong, but that is how I interpreted his description...

[winterh]

Yes, I mean they were encrusted with ice at a depth of 5 ft. The top ice was only about 4 inches thick. When I say encrusted it was not a solid block of hard ice. More like a very compacted slush. When I pulled from water I banged the circulator on dock and it fell off. I have never seen or heard of ice of any kind forming near the bottom. Especially enough that it surrounded my propeller and made it unable to spin.

[DickR]

The only thing I can think of, admittedly getting creative here, is that the recent strong winds, combined with a lot of open water upwind of the docks, pushed a huge mass of broken ice ashore, to the point of piling up multiple feet in height. Over time, water motion would disperse the loose ice mountain and the chunks would rise away from the shore. Any other wild ideas?

[John Mercier]

I was thinking something in the water got on the bubblers and the ice formed around that.
Sort of like seeding clouds to get it to rain.

Just can't think of anything that would be in the water to cause ice to form like that. An algae or maybe the aluminum sulfate they used to fight the CB?

[winterh]

Originally Posted by DickR

The only thing I can think of, admittedly getting creative here, is that the recent strong winds, combined with a lot of open water upwind of the docks, pushed a huge mass of broken ice ashore, to the point of piling up multiple feet in height. Over time, water motion would disperse the loose ice mountain and the chunks would rise away from the shore. Any other wild ideas?

Thats what I was thinking I am in south Wolfeboro bay and the ice that formed there over last few days was all small unconnected pieces that were floated in by the wind. I could see how they could pile up against the dock and circulator all the way to the bottom getting slushier as they went deeper. That would explain the consistency of ice that surrounded it too.