How to keep the water in???????

[davidk]

I have a very large drainage ditch in my yard (approximately 60' x 90' x 4" deep) that I would love to make into a large pond. Does anyone know how I can cheaply and effectively keep water in? I have a small pond on my property - approximately 1200 gallons and I would love to eventually transfer my larger Koi, who have quickly outgrown the smaller pond, to the larger.

Thank you

[B.Scott]

Simplist method would be a rubber liner. Do take into account the need for bottom drain and filtration. Don't go making a big stagnant pool full of (dying) fish. Also realise that if this is a sump of sorts you are lible to have problems with flooding when it rains and the pond overflowing.

B.Scott

[davidk]

Thanks much for the response B. Scott. I was hoping I would get a cheaper solution than the liner. Any idea how water is kept in 10 acre man-made ponds?

[Jagger]

Clay.

Lots of it.

[B.Scott]

Yep, they put in a foot of clay, compact it and also a set of stepped drains for adjusting the water level i.e. during the harvest

B.Scott