I live on the side of a mountain, so one day I might weir my snowmelt
creek to make a pond, but the downside is that it would get flushed
routinely (snowmelt, rainfall etc). In the meantime, I live vicariously
through my friend's pond, a modest 50,000g construction ;~). Every year
they invent a new roof, and they are not getting better at it. This
year's pond roof was grey PVC poles, spaced at about 6 feet, connected
together to make a large oval roof structure, then covered by a plastic
sheet. Inside, they occasionally run a gas-fired campfire, and it's
quite pleasantly mild inside (tall enough to walk around the pond).

It looked great, well... it technically looked very functional, like a
white carport for a Sherman tank in your backyard ;~). However, winter
here (Ottawa Canada) has become milder, resulting in freezing rain
conditions. Their roof collapsed 4 times this year (was removed in Feb.
after the last time). They have asked me to help design next year's
roof. The criteria is that it be completely removable and easily stored
in the summer.

Structurally, it would benefit from 1 (or even 3) centre posts, but these
posts would be above the pond. I've been thinking of a floating
barge-type structure (wood and styrofoam), anchored by rope to 4 sides of
the pond. This would be the base of the centre pole. I would re-use
their grey pvc pole idea (economical and breaks down easily for storage),
but I need to tie them to each other (during ice load, they slid
together, and leaned over). Perhaps metal rings and ropes? It's
difficult to access them when they are up.

Alternately, some sort of an inflatable structure in a dark color, so if
there is an ice sheet, it will melt off faster.

Could someone send me some links or ideas. I heard this was a good place
for pond information again ;~).
--
www.NetMax.tk