"NetMax" wrote in message
.. .
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

I'm not sure from your description how big
the cover needs to be, or exactly its purpose,
but I immediately thought of a shade sail:
http://www.shadesails.com/

They would seem to be adaptable to most
conditions you're describing, although it's
less like an enclosure than you describe.

I use a gazebo with canvas-like cover over
my little pond, but a 10' x 10' structure
probably isn't big enough for your friend's
"lake":
www.academy.com
Keyword search on Gazebo. They show
quite a few different varieties. Academy
is a local (TX) sporting goods store but
these gazebos should be available at
home improvement stores and the like.
The 10'x10' basic models run about US$100,
which is half what I paid for mine a few
years ago. The cover attaches with velcro
and is exceedingly easy to remove when
thunderstorms threaten.

I would have preferred a shade sail if I'd
known about them before I purchased
the gazebo.

Gail
near San Antonio TX USA Zone 8