My wife and I were lucky enough to be able to build a log cabin on some mountain property that has been in the family for generations. On the property is a spring pond (147' x 81') that typically has a foot or two of water on it from early spring to mid-summer. This time of year it dries up and we would like to change that.

The goal is to create a little mountain oasis that has water in it year-round for trout and the local wildlife.

In these early planning stages, I'm trying to figure out the following and would love to get some advice and suggestions from you all.

Water: Pond sits in a low area and collects spring run-off for the main source.
-There is a natural spring that I'm working on developing about 100 yards away. I plan to gravity feed the spring and I estimate it to be 1/2-1 gpm once developed.

-I'm estimating the pond to be around 500,000 gallons and am hoping to get an average of 5' of depth. If we can go deeper without blasting we will, but I think that's going to be about the max based off the septic dig not far away. I've heard most trout really need areas of 6-9' ft but can do with much less if you have water movement.

Questions: What is the best way to figure out evaporation for the area?

I have a ton of other questions, but I think the water is obviously going to be the most important part so I'll start there.

I can't help you at all, but I'd love for you to journal this process. This will be fun to watch and helpful to others.

That sounds like a very cool project. Fantastic setting too!

I am no expert at all, but 1/2 to 1 gpm does not seem like much "water movement". Is that all it takes to sustain trout in a shallower BOW? Does the spring run all year long? DO you have clay on the property to line the pond with?

I second the request for a Journal. Start a thread as soon as you "break ground" to log your progress.

Agreed, I'm hoping that spring will be enough to just keep the thing full. I'm planning on aeration, and perhaps some type of water feature to circulate water.

Also no expert! But, 1 gpm is 1440 gals per day or 525,600 gals per year. Supplement that with rain and snow melt and I think it should be ok. Subtract some evaporation and wicking . My well produces less than that(1/10 gpm) but goes into a 2,500 gal tank that stays full.

Getting a little further along in the planning process, and have a few questions for you guys!

I'm seeing most smaller ponds utilize filters and skimmers, but this doesn't seem to apply to anything over 30,000 gallons or so. I'd love to keep this thing crystal clear, but I'm not sure if filters and skimmers would be necessary or even possible for a 300,000-500,000 gallon pond?

Guessing most people just use aeration on larger ponds?

So far I've decided to go ahead and line the pond and will do rock over that to keep the moose from popping holes in the liner. Seems the small rock is also great for natural bacteria and the entire pond ecosystem.

May need to install a drain pipe under the liner if we hit water, and still working out how this may work if you have suggestions?

Also going to incorporate about a 100-foot cascading stream to help with aeration and water movement for the trout.

I'd be curious to get everyone's thoughts on filters and skimmers in large ponds, and the options we have?

Attached is the Sattelite view.