I changed back to my original plans. The spring is only 40 ft or so long with a vertical drop of about 24". In order to get the tank installed I'd have had to dig anyway. So the digging wasn't "extra". Next due to the fact that the soil is sand with a bit of silt 5% and clay 8%(per jar test) the bottom should be easy to maintain as a pebbly brook like setting.

I built a small earth dam about a foot tall and dug down about 18" For a max depth of 30" or so. The deep area is near the centre with a 4" drain pipe. This area is about 5' or so in diameter. The next step up averages 20" in depth. This area is about 8' in diameter. Lastly the whole thing is about 9'X12' with a min depth of about 14".

Drains and "dredging".
The 4" drain seems to keep up fine. It drains the spring from full pool in about 5 mins. It takes the spring about an hour to fill the pool. The 4" pipe will suck the water from the top of the water and set it's depth. (Should I use a siphon instead and take from the bottom?) I will be putting in a "emergency" spillway with the 6" pipe. But never expect it to be used.
Dredging..

I will be attaching a "T" fitting. It will go from the 4" to 1 1/4" on this I will attach a ball valve and a section of flexible sump hose. I will use this to "vacuum" the pool bottom periodically.

Next steps...

I will be adding soil to the dam to make it more substantial (Now it's just a big mud pie, lol) and adding boards to make a "deck" frame. I plan on putting the boards in place first. Attaching hardware cloth to it. Then burying the wire in soil. This is to keep out digging critters. Do you think it will be OK to leave the water go through the wire? I know what they say about galvanised . But it's a tiny amount with lots of water.


On to the deck frame I will build a deck and small pole building. In the deck I plan on leaving a 4'x8' hole. The sides and roof of the pole building will be tin. I was thinking I should also make one or two of the roof panels plastic so light shines in some... Do you think they need more?


P.S. My friend the Blue Heron was at the pond today again. That JERK!

Last edited by Stanb999; 04/13/12 05:22 AM.