Messages

1

Pond Construction & Filtration / Re: Unusual pool to pond conversion

« on: October 07, 2009, 08:35:26 PM »

Hi again folks!

It's busy season here at home, with improvement projects inside and out.  I never know when these fits of motivation are going to arise, but I try to make the most of them when they happen.   

Thanks for your input so far - as a complete pond newbie it's really helpful.

I think I probably didn't explain myself as well as I would have liked to above.  My inspiration is Erik Kilk's pool conversion at -  http://kilk.com/pond/  - but with some significant differences due to building my pond within an intact pool.

I just want to fill the swimming pool up to "pond depth" (about 30 inches) in such a way that (a) I don't get cracks in the pool walls from external hydrostatic pressure, and (b) I don't get hydrostatic "heaving" from below whatever I use for a liner (i.e. water pushing up from below the liner).  Normally, to avoid this second issue, you knock holes in the pool wall, but I don't want to do that.  It really doesn't matter to me whether the fill is dirt or stone, as long as it will accomplish both (a) and (b) above.  In fact, soil would be less expensive, so if it avoids anaerobic bacteria issues I'm all for it.  Likewise, I'm fine with using a regular liner rather than filter cloth, so long as it all works together.  The 30 inch depth is important, as I don't want to have a fence around the pond.

I'm not looking to use the "fill layer" as filtration, or to use the pool plumbing to recycle or filter the pond.  I'll use regular pond-grade pumps and filtration.  The whole idea of keeping the pool drain clear with the stand pipe is so I can control water buildup within the pool (but below my pond) by occasionally draining the area below the pond (especially before draining the pond itself).

So I guess a better way of phrasing my original question is this - if you wanted to preserve an existing pool and convert it to a 30-inch deep pond without knocking holes in the bottom, what do you think would be the best way to do it?

Thanks in advance!

Buster
Northern Virginia

2

Pond Construction & Filtration / Re: Unusual pool to pond conversion

« on: September 29, 2009, 12:53:46 AM »

I should note - I am not planning on having koi in this pond, but enough goldfish to keep the pond in balance.  I also do not intend to have rocks above the filter fabric layer - the pond bottom and sides will be filter fabric over the crushed stone below and over the sandbags forming the shelves/planters.

Thanks!
Buster

3

Pond Construction & Filtration / Unusual pool to pond conversion

« on: September 29, 2009, 12:40:58 AM »

Hi folks!

I need some feedback.  I want to convert my in-ground kidney-shaped gunite pool into a pond, but without damaging the existing pool.  The pool has not been used or serviced for several years, so I expect most of the chlorine will have leached out of the gunite and evaporated.  What I propose to do is (1) vertically stand a perforated metal culvert pipe wrapped in filter fabric centered over the pool drain (like a vertical french drain) so that the drain is protected and I can drain the pool to the bottom if necessary; (2) fill the pool with crushed stone up to about 40 inches below the proposed surface (up to the top of the culvert pipe); (3) cover the stone and culvert with a couple of layers of heavy filter fabric to form a level porous surface; (4) use sandbags and filter fabric to create shelves and planters (possibly using rubber liner to isolate planters from the pond); and (5) fill the pool with water and stock it with plants and fish. 

Note that there is no liner, and therefore no issue of hydrostatic pressure either between the inside/outside of the pool, or between the rock-filled area and the pond.  The water will fill the pool all the way to the bottom.

I'm aware of the other requirements for a healthy pond system.  The water above the filter fabric "liner" will flow continuously, and I will probably use a biological filtration system.  I just need to know if anyone is aware of a problem with doing a pool conversion the way I have described it (e.g. stagnation of the water at the pool bottom, etc).  Thanks!

Buster Harvey
Northern Virginia